From ce32ae313406e0f5cff6787b35b25e313c64bdf1 Mon Sep 17 00:00:00 2001
From: StillHammer <alexistrouve.pro@gmail.com>
Date: Thu, 4 Dec 2025 20:57:51 +0800
Subject: [PATCH] Migration Gitea

---
 .claude/settings.local.json   |   18 +-
 CLAUDE.md                     |  256 ++--
 docs/API.md                   | 1122 ++++++++--------
 nul                           |    1 +
 public/app.js                 | 2258 ++++++++++++++++----------------
 public/index.html             | 1154 ++++++++---------
 public/style.css              | 1432 ++++++++++-----------
 src/server.js                 | 2274 ++++++++++++++++-----------------
 src/services/conversion.js    |  290 ++---
 src/services/summarize.js     |  390 +++---
 src/services/transcription.js |  356 +++---
 src/services/translation.js   |  542 ++++----
 src/services/youtube.js       |  582 ++++-----
 start-server.bat              |  122 +-
 start-server.sh               |  116 +-
 15 files changed, 5457 insertions(+), 5456 deletions(-)
 create mode 100644 nul

diff --git a/.claude/settings.local.json b/.claude/settings.local.json
index 919dca9..025a3c6 100644
--- a/.claude/settings.local.json
+++ b/.claude/settings.local.json
@@ -1,9 +1,9 @@
-{
-  "permissions": {
-    "allow": [
-      "Bash(npm run server:*)"
-    ],
-    "deny": [],
-    "ask": []
-  }
-}
+{
+  "permissions": {
+    "allow": [
+      "Bash(npm run server:*)"
+    ],
+    "deny": [],
+    "ask": []
+  }
+}
diff --git a/CLAUDE.md b/CLAUDE.md
index d6c04b3..3b00787 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -1,128 +1,128 @@
-# Video to MP3 Transcriptor - Instructions pour Claude
-
-## À propos du projet
-Ce projet est une API Node.js/Express pour télécharger des vidéos YouTube en MP3, les transcrire, les traduire et les résumer.
-
-## Documentation
-
-### Documentation API
-La documentation complète de l'API se trouve dans **`docs/API.md`**.
-
-**IMPORTANT** : Cette documentation doit TOUJOURS être maintenue à jour. Chaque fois qu'un endpoint est modifié, ajouté ou supprimé, la documentation doit être mise à jour en conséquence.
-
-### Responsabilités de maintenance de la documentation
-
-Quand tu modifies le code, tu DOIS mettre à jour `docs/API.md` si :
-- Un nouvel endpoint est ajouté
-- Un endpoint existant est modifié (paramètres, réponses, etc.)
-- Un endpoint est supprimé
-- Les modèles par défaut changent
-- De nouveaux paramètres sont ajoutés
-- Le format des réponses change
-
-## Structure du projet
-
-```
-videotoMP3Transcriptor/
-├── docs/
-│   └── API.md              # Documentation complète de l'API
-├── src/
-│   ├── server.js           # Serveur Express et routes API
-│   ├── services/
-│   │   ├── youtube.js      # Téléchargement YouTube
-│   │   ├── transcription.js # Transcription OpenAI
-│   │   ├── translation.js  # Traduction GPT
-│   │   └── summarize.js    # Résumé GPT-5.1
-│   └── cli.js              # Interface en ligne de commande
-├── public/                 # Interface web (si présente)
-├── output/                 # Répertoire de sortie par défaut
-├── .env                    # Variables d'environnement
-└── package.json
-
-```
-
-## Configuration
-
-### Port du serveur
-- Port par défaut : **8888**
-- Configurable via `process.env.PORT` dans `.env`
-
-### Modèles par défaut
-- **Transcription** : `gpt-4o-mini-transcribe`
-- **Résumé** : `gpt-5.1`
-- **Traduction** : `gpt-4o-mini` (hardcodé)
-
-### Variables d'environnement requises
-```env
-OPENAI_API_KEY=sk-...
-PORT=8888                  # optionnel
-OUTPUT_DIR=./output        # optionnel
-```
-
-## Commandes importantes
-
-```bash
-# Lancer le serveur
-npm run server
-
-# Lancer le CLI
-npm run cli
-
-# Installer les dépendances
-npm install
-```
-
-## Points d'attention
-
-### Paramètres outputPath
-Tous les endpoints supportent maintenant un paramètre `outputPath` optionnel pour spécifier un répertoire de sortie personnalisé. Si non spécifié, le répertoire par défaut `OUTPUT_DIR` est utilisé.
-
-### Modèles de transcription disponibles
-- `gpt-4o-mini-transcribe` (par défaut) - Rapide et économique
-- `gpt-4o-transcribe` - Qualité supérieure
-- `whisper-1` - Modèle original Whisper (supporte plus de formats)
-
-### Formats de sortie
-- **Transcription** : txt, json, srt, vtt (selon le modèle)
-- **Traduction** : txt
-- **Résumé** : txt
-
-## Règles de développement
-
-1. **Documentation d'abord** : Avant de modifier un endpoint, vérifie `docs/API.md`
-2. **Après modification** : Mets à jour immédiatement `docs/API.md`
-3. **Tests** : Redémarre le serveur après chaque modification
-4. **Cohérence** : Garde la même structure de réponse pour tous les endpoints similaires
-
-## Architecture des endpoints
-
-### Endpoints streaming (SSE)
-- `/download-stream`
-- `/process-stream`
-- `/summarize-stream`
-
-Ces endpoints utilisent Server-Sent Events pour envoyer des mises à jour de progression en temps réel.
-
-### Endpoints non-streaming
-- `/download`
-- `/process`
-- Tous les endpoints POST avec upload de fichiers
-
-Ces endpoints retournent une réponse unique une fois le traitement terminé.
-
-## Maintenance
-
-Lors de l'ajout de nouvelles fonctionnalités :
-1. Implémente la fonctionnalité dans le service approprié (`src/services/`)
-2. Ajoute les routes dans `src/server.js`
-3. **Mets à jour `docs/API.md` IMMÉDIATEMENT**
-4. Teste l'endpoint avec curl ou Postman
-5. Vérifie que la documentation est claire et complète
-
-## Notes importantes
-
-- Le serveur doit toujours être sur le port **8888**
-- Les clés API OpenAI sont requises pour transcription/traduction/résumé
-- Le répertoire `output/` est créé automatiquement si inexistant
-- Les fichiers uploadés sont stockés dans `OUTPUT_DIR`
-- Les vidéos YouTube sont téléchargées en MP3 automatiquement
+# Video to MP3 Transcriptor - Instructions pour Claude
+
+## À propos du projet
+Ce projet est une API Node.js/Express pour télécharger des vidéos YouTube en MP3, les transcrire, les traduire et les résumer.
+
+## Documentation
+
+### Documentation API
+La documentation complète de l'API se trouve dans **`docs/API.md`**.
+
+**IMPORTANT** : Cette documentation doit TOUJOURS être maintenue à jour. Chaque fois qu'un endpoint est modifié, ajouté ou supprimé, la documentation doit être mise à jour en conséquence.
+
+### Responsabilités de maintenance de la documentation
+
+Quand tu modifies le code, tu DOIS mettre à jour `docs/API.md` si :
+- Un nouvel endpoint est ajouté
+- Un endpoint existant est modifié (paramètres, réponses, etc.)
+- Un endpoint est supprimé
+- Les modèles par défaut changent
+- De nouveaux paramètres sont ajoutés
+- Le format des réponses change
+
+## Structure du projet
+
+```
+videotoMP3Transcriptor/
+├── docs/
+│   └── API.md              # Documentation complète de l'API
+├── src/
+│   ├── server.js           # Serveur Express et routes API
+│   ├── services/
+│   │   ├── youtube.js      # Téléchargement YouTube
+│   │   ├── transcription.js # Transcription OpenAI
+│   │   ├── translation.js  # Traduction GPT
+│   │   └── summarize.js    # Résumé GPT-5.1
+│   └── cli.js              # Interface en ligne de commande
+├── public/                 # Interface web (si présente)
+├── output/                 # Répertoire de sortie par défaut
+├── .env                    # Variables d'environnement
+└── package.json
+
+```
+
+## Configuration
+
+### Port du serveur
+- Port par défaut : **8888**
+- Configurable via `process.env.PORT` dans `.env`
+
+### Modèles par défaut
+- **Transcription** : `gpt-4o-mini-transcribe`
+- **Résumé** : `gpt-5.1`
+- **Traduction** : `gpt-4o-mini` (hardcodé)
+
+### Variables d'environnement requises
+```env
+OPENAI_API_KEY=sk-...
+PORT=8888                  # optionnel
+OUTPUT_DIR=./output        # optionnel
+```
+
+## Commandes importantes
+
+```bash
+# Lancer le serveur
+npm run server
+
+# Lancer le CLI
+npm run cli
+
+# Installer les dépendances
+npm install
+```
+
+## Points d'attention
+
+### Paramètres outputPath
+Tous les endpoints supportent maintenant un paramètre `outputPath` optionnel pour spécifier un répertoire de sortie personnalisé. Si non spécifié, le répertoire par défaut `OUTPUT_DIR` est utilisé.
+
+### Modèles de transcription disponibles
+- `gpt-4o-mini-transcribe` (par défaut) - Rapide et économique
+- `gpt-4o-transcribe` - Qualité supérieure
+- `whisper-1` - Modèle original Whisper (supporte plus de formats)
+
+### Formats de sortie
+- **Transcription** : txt, json, srt, vtt (selon le modèle)
+- **Traduction** : txt
+- **Résumé** : txt
+
+## Règles de développement
+
+1. **Documentation d'abord** : Avant de modifier un endpoint, vérifie `docs/API.md`
+2. **Après modification** : Mets à jour immédiatement `docs/API.md`
+3. **Tests** : Redémarre le serveur après chaque modification
+4. **Cohérence** : Garde la même structure de réponse pour tous les endpoints similaires
+
+## Architecture des endpoints
+
+### Endpoints streaming (SSE)
+- `/download-stream`
+- `/process-stream`
+- `/summarize-stream`
+
+Ces endpoints utilisent Server-Sent Events pour envoyer des mises à jour de progression en temps réel.
+
+### Endpoints non-streaming
+- `/download`
+- `/process`
+- Tous les endpoints POST avec upload de fichiers
+
+Ces endpoints retournent une réponse unique une fois le traitement terminé.
+
+## Maintenance
+
+Lors de l'ajout de nouvelles fonctionnalités :
+1. Implémente la fonctionnalité dans le service approprié (`src/services/`)
+2. Ajoute les routes dans `src/server.js`
+3. **Mets à jour `docs/API.md` IMMÉDIATEMENT**
+4. Teste l'endpoint avec curl ou Postman
+5. Vérifie que la documentation est claire et complète
+
+## Notes importantes
+
+- Le serveur doit toujours être sur le port **8888**
+- Les clés API OpenAI sont requises pour transcription/traduction/résumé
+- Le répertoire `output/` est créé automatiquement si inexistant
+- Les fichiers uploadés sont stockés dans `OUTPUT_DIR`
+- Les vidéos YouTube sont téléchargées en MP3 automatiquement
diff --git a/docs/API.md b/docs/API.md
index 7b02be2..c54bd38 100644
--- a/docs/API.md
+++ b/docs/API.md
@@ -1,561 +1,561 @@
-# API Documentation - Video to MP3 Transcriptor
-
-## Base URL
-```
-http://localhost:8888
-```
-
-## Table of Contents
-- [Health & Info](#health--info)
-- [Download Endpoints](#download-endpoints)
-- [Transcription Endpoints](#transcription-endpoints)
-- [Translation Endpoints](#translation-endpoints)
-- [Summarization Endpoints](#summarization-endpoints)
-- [File Management](#file-management)
-
----
-
-## Health & Info
-
-### GET /health
-Health check endpoint.
-
-**Response:**
-```json
-{
-  "status": "ok",
-  "timestamp": "2025-11-28T12:00:00.000Z"
-}
-```
-
-### GET /api
-Get API information and available endpoints.
-
-**Response:**
-```json
-{
-  "name": "Video to MP3 Transcriptor API",
-  "version": "1.0.0",
-  "endpoints": { ... }
-}
-```
-
-### GET /info
-Get information about a YouTube video or playlist.
-
-**Query Parameters:**
-- `url` (required): YouTube URL
-
-**Example:**
-```bash
-curl "http://localhost:8888/info?url=https://www.youtube.com/watch?v=VIDEO_ID"
-```
-
-**Response:**
-```json
-{
-  "success": true,
-  "title": "Video Title",
-  "type": "video",
-  "duration": 300,
-  "channel": "Channel Name",
-  "videoCount": 1
-}
-```
-
----
-
-## Download Endpoints
-
-### GET /download-stream
-Download YouTube video(s) to MP3 with Server-Sent Events (SSE) progress updates.
-
-**Query Parameters:**
-- `url` (required): YouTube URL
-- `outputPath` (optional): Custom output directory path
-
-**Example:**
-```bash
-curl "http://localhost:8888/download-stream?url=https://www.youtube.com/watch?v=VIDEO_ID"
-```
-
-**SSE Events:**
-- `info`: Video/playlist information
-- `progress`: Download progress updates
-- `video-complete`: Individual video completion
-- `complete`: All downloads complete
-- `error`: Error occurred
-
-### POST /download
-Download YouTube video(s) to MP3 (non-streaming).
-
-**Body Parameters:**
-```json
-{
-  "url": "https://www.youtube.com/watch?v=VIDEO_ID",
-  "outputPath": "./custom/path"  // optional
-}
-```
-
-**Example:**
-```bash
-curl -X POST http://localhost:8888/download \
-  -H "Content-Type: application/json" \
-  -d '{"url":"https://www.youtube.com/watch?v=VIDEO_ID"}'
-```
-
-**Response:**
-```json
-{
-  "success": true,
-  "playlistTitle": null,
-  "totalVideos": 1,
-  "successCount": 1,
-  "failCount": 0,
-  "videos": [
-    {
-      "success": true,
-      "title": "Video Title",
-      "filePath": "./output/video.mp3",
-      "fileUrl": "/files/video.mp3"
-    }
-  ]
-}
-```
-
----
-
-## Transcription Endpoints
-
-### POST /transcribe
-Transcribe an existing audio file.
-
-**Body Parameters:**
-```json
-{
-  "filePath": "./output/audio.mp3",
-  "language": "en",  // optional (auto-detect if not specified)
-  "format": "txt",   // optional: txt, json, srt, vtt
-  "model": "gpt-4o-mini-transcribe",  // optional: gpt-4o-mini-transcribe (default), gpt-4o-transcribe, whisper-1
-  "outputPath": "./custom/path"  // optional
-}
-```
-
-**Available Models:**
-- `gpt-4o-mini-transcribe` (default) - Fast and cost-effective
-- `gpt-4o-transcribe` - Higher quality
-- `whisper-1` - Original Whisper model (supports more formats)
-
-**Example:**
-```bash
-curl -X POST http://localhost:8888/transcribe \
-  -H "Content-Type: application/json" \
-  -d '{
-    "filePath": "./output/audio.mp3",
-    "language": "en",
-    "model": "gpt-4o-mini-transcribe"
-  }'
-```
-
-**Response:**
-```json
-{
-  "success": true,
-  "filePath": "./output/audio.mp3",
-  "transcriptionPath": "./output/audio.txt",
-  "transcriptionUrl": "/files/audio.txt",
-  "text": "Transcribed text content..."
-}
-```
-
-### POST /upload-transcribe
-Upload and transcribe audio files.
-
-**Form Data:**
-- `files`: Audio file(s) (multiple files supported, max 50)
-- `language`: Language code (optional)
-- `model`: Transcription model (optional, default: gpt-4o-mini-transcribe)
-- `outputPath`: Custom output directory (optional)
-
-**Example:**
-```bash
-curl -X POST http://localhost:8888/upload-transcribe \
-  -F "files=@audio1.mp3" \
-  -F "files=@audio2.mp3" \
-  -F "language=en" \
-  -F "model=gpt-4o-mini-transcribe"
-```
-
-**Response:**
-```json
-{
-  "success": true,
-  "totalFiles": 2,
-  "successCount": 2,
-  "failCount": 0,
-  "results": [
-    {
-      "success": true,
-      "fileName": "audio1.mp3",
-      "transcriptionPath": "./output/audio1.txt",
-      "transcriptionUrl": "/files/audio1.txt",
-      "text": "Transcription..."
-    }
-  ]
-}
-```
-
-### GET /process-stream
-Download + Transcribe with SSE progress updates.
-
-**Query Parameters:**
-- `url` (required): YouTube URL
-- `language` (optional): Language code
-- `model` (optional): Transcription model (default: gpt-4o-mini-transcribe)
-- `outputPath` (optional): Custom output directory
-
-**Example:**
-```bash
-curl "http://localhost:8888/process-stream?url=https://www.youtube.com/watch?v=VIDEO_ID&language=en&model=gpt-4o-mini-transcribe"
-```
-
-**SSE Events:**
-- `info`: Video information
-- `progress`: Progress updates (downloading or transcribing)
-- `video-complete`: Download complete
-- `transcribe-complete`: Transcription complete
-- `complete`: All operations complete
-- `error`: Error occurred
-
-### POST /process
-Download + Transcribe (non-streaming).
-
-**Body Parameters:**
-```json
-{
-  "url": "https://www.youtube.com/watch?v=VIDEO_ID",
-  "language": "en",  // optional
-  "format": "txt",   // optional
-  "model": "gpt-4o-mini-transcribe",  // optional
-  "outputPath": "./custom/path"  // optional
-}
-```
-
-**Example:**
-```bash
-curl -X POST http://localhost:8888/process \
-  -H "Content-Type: application/json" \
-  -d '{
-    "url": "https://www.youtube.com/watch?v=VIDEO_ID",
-    "language": "en",
-    "model": "gpt-4o-mini-transcribe"
-  }'
-```
-
-**Response:**
-```json
-{
-  "success": true,
-  "playlistTitle": null,
-  "totalVideos": 1,
-  "downloadedCount": 1,
-  "transcribedCount": 1,
-  "results": [
-    {
-      "title": "Video Title",
-      "downloadSuccess": true,
-      "audioPath": "./output/video.mp3",
-      "audioUrl": "/files/video.mp3",
-      "transcriptionSuccess": true,
-      "transcriptionPath": "./output/video.txt",
-      "transcriptionUrl": "/files/video.txt",
-      "text": "Transcription..."
-    }
-  ]
-}
-```
-
----
-
-## Translation Endpoints
-
-### GET /languages
-Get available translation languages.
-
-**Response:**
-```json
-{
-  "languages": {
-    "en": "English",
-    "fr": "French",
-    "es": "Spanish",
-    "de": "German",
-    "zh": "Chinese",
-    "ja": "Japanese",
-    ...
-  }
-}
-```
-
-### POST /translate
-Translate text.
-
-**Body Parameters:**
-```json
-{
-  "text": "Text to translate",
-  "targetLang": "fr",  // required: target language code
-  "sourceLang": "en"   // optional: source language (auto-detect if not specified)
-}
-```
-
-**Example:**
-```bash
-curl -X POST http://localhost:8888/translate \
-  -H "Content-Type: application/json" \
-  -d '{
-    "text": "Hello, how are you?",
-    "targetLang": "fr"
-  }'
-```
-
-**Response:**
-```json
-{
-  "success": true,
-  "originalText": "Hello, how are you?",
-  "translatedText": "Bonjour, comment allez-vous ?",
-  "targetLanguage": "French",
-  "sourceLanguage": "auto-detected",
-  "chunks": 1
-}
-```
-
-### POST /translate-file
-Translate uploaded text files.
-
-**Form Data:**
-- `files`: Text file(s) (.txt, multiple files supported, max 50)
-- `targetLang`: Target language code (required)
-- `sourceLang`: Source language code (optional)
-- `outputPath`: Custom output directory (optional)
-
-**Example:**
-```bash
-curl -X POST http://localhost:8888/translate-file \
-  -F "files=@document.txt" \
-  -F "targetLang=fr" \
-  -F "sourceLang=en"
-```
-
-**Response:**
-```json
-{
-  "success": true,
-  "totalFiles": 1,
-  "successCount": 1,
-  "failCount": 0,
-  "results": [
-    {
-      "success": true,
-      "fileName": "document.txt",
-      "translationPath": "./output/document_fr.txt",
-      "translationUrl": "/files/document_fr.txt",
-      "translatedText": "Translated content..."
-    }
-  ]
-}
-```
-
----
-
-## Summarization Endpoints
-
-### GET /summary-styles
-Get available summary styles.
-
-**Response:**
-```json
-{
-  "styles": {
-    "concise": "A brief summary capturing main points",
-    "detailed": "A comprehensive summary with nuances",
-    "bullet": "Key points as bullet points"
-  }
-}
-```
-
-### POST /summarize
-Summarize text using GPT-5.1.
-
-**Body Parameters:**
-```json
-{
-  "text": "Long text to summarize...",
-  "style": "concise",  // optional: concise (default), detailed, bullet
-  "language": "same",  // optional: 'same' (default) or language code
-  "model": "gpt-5.1"   // optional: default is gpt-5.1
-}
-```
-
-**Example:**
-```bash
-curl -X POST http://localhost:8888/summarize \
-  -H "Content-Type: application/json" \
-  -d '{
-    "text": "Long article content...",
-    "style": "bullet",
-    "language": "same"
-  }'
-```
-
-**Response:**
-```json
-{
-  "success": true,
-  "summary": "Summary content...",
-  "model": "gpt-5.1",
-  "style": "bullet",
-  "inputLength": 5000,
-  "chunks": 1
-}
-```
-
-### POST /summarize-file
-Summarize uploaded text files using GPT-5.1.
-
-**Form Data:**
-- `files`: Text file(s) (.txt, multiple files supported, max 50)
-- `style`: Summary style (optional, default: concise)
-- `language`: Output language (optional, default: same)
-- `model`: AI model (optional, default: gpt-5.1)
-- `outputPath`: Custom output directory (optional)
-
-**Example:**
-```bash
-curl -X POST http://localhost:8888/summarize-file \
-  -F "files=@article.txt" \
-  -F "style=detailed" \
-  -F "language=same"
-```
-
-**Response:**
-```json
-{
-  "success": true,
-  "totalFiles": 1,
-  "successCount": 1,
-  "failCount": 0,
-  "results": [
-    {
-      "success": true,
-      "fileName": "article.txt",
-      "summaryPath": "./output/article_summary.txt",
-      "summaryUrl": "/files/article_summary.txt",
-      "summary": "Summary content...",
-      "model": "gpt-5.1",
-      "chunks": 1
-    }
-  ]
-}
-```
-
-### GET /summarize-stream
-Full pipeline: Download -> Transcribe -> Summarize with SSE progress.
-
-**Query Parameters:**
-- `url` (required): YouTube URL
-- `style` (optional): Summary style (default: concise)
-- `language` (optional): Output language (default: same)
-- `model` (optional): Transcription model (default: gpt-4o-mini-transcribe)
-- `outputPath` (optional): Custom output directory
-
-**Example:**
-```bash
-curl "http://localhost:8888/summarize-stream?url=https://www.youtube.com/watch?v=VIDEO_ID&style=bullet&model=gpt-4o-mini-transcribe"
-```
-
-**SSE Events:**
-- `info`: Video information
-- `progress`: Progress updates (downloading, transcribing, or summarizing)
-- `video-complete`: Download complete
-- `transcribe-complete`: Transcription complete
-- `summarize-complete`: Summary complete
-- `complete`: All operations complete
-- `error`: Error occurred
-
----
-
-## File Management
-
-### GET /files-list
-List all downloaded/generated files.
-
-**Example:**
-```bash
-curl http://localhost:8888/files-list
-```
-
-**Response:**
-```json
-{
-  "files": [
-    {
-      "name": "video.mp3",
-      "url": "/files/video.mp3",
-      "path": "./output/video.mp3"
-    },
-    {
-      "name": "video.txt",
-      "url": "/files/video.txt",
-      "path": "./output/video.txt"
-    }
-  ]
-}
-```
-
-### GET /files/:filename
-Serve a specific file.
-
-**Example:**
-```bash
-curl http://localhost:8888/files/video.mp3 --output video.mp3
-```
-
----
-
-## Error Responses
-
-All endpoints return error responses in the following format:
-
-```json
-{
-  "error": "Error message describing what went wrong"
-}
-```
-
-Common HTTP status codes:
-- `400` - Bad Request (missing required parameters)
-- `500` - Internal Server Error (processing failed)
-
----
-
-## Notes
-
-### Output Paths
-All endpoints that support `outputPath` parameter:
-- If not specified, files are saved to the default `OUTPUT_DIR` (./output)
-- If specified, files are saved to the custom path provided
-
-### Models
-- **Transcription**: Default is `gpt-4o-mini-transcribe` (cost-effective)
-- **Summarization**: Default is `gpt-5.1` (latest GPT model)
-- **Translation**: Uses `gpt-4o-mini` (hardcoded)
-
-### File Formats
-- **Audio**: MP3, WAV, M4A, OGG, FLAC
-- **Text**: TXT files
-- **Transcription outputs**: TXT, JSON, SRT, VTT (depending on model)
-
-### API Key
-Ensure `OPENAI_API_KEY` is set in your `.env` file for transcription, translation, and summarization features to work.
+# API Documentation - Video to MP3 Transcriptor
+
+## Base URL
+```
+http://localhost:8888
+```
+
+## Table of Contents
+- [Health & Info](#health--info)
+- [Download Endpoints](#download-endpoints)
+- [Transcription Endpoints](#transcription-endpoints)
+- [Translation Endpoints](#translation-endpoints)
+- [Summarization Endpoints](#summarization-endpoints)
+- [File Management](#file-management)
+
+---
+
+## Health & Info
+
+### GET /health
+Health check endpoint.
+
+**Response:**
+```json
+{
+  "status": "ok",
+  "timestamp": "2025-11-28T12:00:00.000Z"
+}
+```
+
+### GET /api
+Get API information and available endpoints.
+
+**Response:**
+```json
+{
+  "name": "Video to MP3 Transcriptor API",
+  "version": "1.0.0",
+  "endpoints": { ... }
+}
+```
+
+### GET /info
+Get information about a YouTube video or playlist.
+
+**Query Parameters:**
+- `url` (required): YouTube URL
+
+**Example:**
+```bash
+curl "http://localhost:8888/info?url=https://www.youtube.com/watch?v=VIDEO_ID"
+```
+
+**Response:**
+```json
+{
+  "success": true,
+  "title": "Video Title",
+  "type": "video",
+  "duration": 300,
+  "channel": "Channel Name",
+  "videoCount": 1
+}
+```
+
+---
+
+## Download Endpoints
+
+### GET /download-stream
+Download YouTube video(s) to MP3 with Server-Sent Events (SSE) progress updates.
+
+**Query Parameters:**
+- `url` (required): YouTube URL
+- `outputPath` (optional): Custom output directory path
+
+**Example:**
+```bash
+curl "http://localhost:8888/download-stream?url=https://www.youtube.com/watch?v=VIDEO_ID"
+```
+
+**SSE Events:**
+- `info`: Video/playlist information
+- `progress`: Download progress updates
+- `video-complete`: Individual video completion
+- `complete`: All downloads complete
+- `error`: Error occurred
+
+### POST /download
+Download YouTube video(s) to MP3 (non-streaming).
+
+**Body Parameters:**
+```json
+{
+  "url": "https://www.youtube.com/watch?v=VIDEO_ID",
+  "outputPath": "./custom/path"  // optional
+}
+```
+
+**Example:**
+```bash
+curl -X POST http://localhost:8888/download \
+  -H "Content-Type: application/json" \
+  -d '{"url":"https://www.youtube.com/watch?v=VIDEO_ID"}'
+```
+
+**Response:**
+```json
+{
+  "success": true,
+  "playlistTitle": null,
+  "totalVideos": 1,
+  "successCount": 1,
+  "failCount": 0,
+  "videos": [
+    {
+      "success": true,
+      "title": "Video Title",
+      "filePath": "./output/video.mp3",
+      "fileUrl": "/files/video.mp3"
+    }
+  ]
+}
+```
+
+---
+
+## Transcription Endpoints
+
+### POST /transcribe
+Transcribe an existing audio file.
+
+**Body Parameters:**
+```json
+{
+  "filePath": "./output/audio.mp3",
+  "language": "en",  // optional (auto-detect if not specified)
+  "format": "txt",   // optional: txt, json, srt, vtt
+  "model": "gpt-4o-mini-transcribe",  // optional: gpt-4o-mini-transcribe (default), gpt-4o-transcribe, whisper-1
+  "outputPath": "./custom/path"  // optional
+}
+```
+
+**Available Models:**
+- `gpt-4o-mini-transcribe` (default) - Fast and cost-effective
+- `gpt-4o-transcribe` - Higher quality
+- `whisper-1` - Original Whisper model (supports more formats)
+
+**Example:**
+```bash
+curl -X POST http://localhost:8888/transcribe \
+  -H "Content-Type: application/json" \
+  -d '{
+    "filePath": "./output/audio.mp3",
+    "language": "en",
+    "model": "gpt-4o-mini-transcribe"
+  }'
+```
+
+**Response:**
+```json
+{
+  "success": true,
+  "filePath": "./output/audio.mp3",
+  "transcriptionPath": "./output/audio.txt",
+  "transcriptionUrl": "/files/audio.txt",
+  "text": "Transcribed text content..."
+}
+```
+
+### POST /upload-transcribe
+Upload and transcribe audio files.
+
+**Form Data:**
+- `files`: Audio file(s) (multiple files supported, max 50)
+- `language`: Language code (optional)
+- `model`: Transcription model (optional, default: gpt-4o-mini-transcribe)
+- `outputPath`: Custom output directory (optional)
+
+**Example:**
+```bash
+curl -X POST http://localhost:8888/upload-transcribe \
+  -F "files=@audio1.mp3" \
+  -F "files=@audio2.mp3" \
+  -F "language=en" \
+  -F "model=gpt-4o-mini-transcribe"
+```
+
+**Response:**
+```json
+{
+  "success": true,
+  "totalFiles": 2,
+  "successCount": 2,
+  "failCount": 0,
+  "results": [
+    {
+      "success": true,
+      "fileName": "audio1.mp3",
+      "transcriptionPath": "./output/audio1.txt",
+      "transcriptionUrl": "/files/audio1.txt",
+      "text": "Transcription..."
+    }
+  ]
+}
+```
+
+### GET /process-stream
+Download + Transcribe with SSE progress updates.
+
+**Query Parameters:**
+- `url` (required): YouTube URL
+- `language` (optional): Language code
+- `model` (optional): Transcription model (default: gpt-4o-mini-transcribe)
+- `outputPath` (optional): Custom output directory
+
+**Example:**
+```bash
+curl "http://localhost:8888/process-stream?url=https://www.youtube.com/watch?v=VIDEO_ID&language=en&model=gpt-4o-mini-transcribe"
+```
+
+**SSE Events:**
+- `info`: Video information
+- `progress`: Progress updates (downloading or transcribing)
+- `video-complete`: Download complete
+- `transcribe-complete`: Transcription complete
+- `complete`: All operations complete
+- `error`: Error occurred
+
+### POST /process
+Download + Transcribe (non-streaming).
+
+**Body Parameters:**
+```json
+{
+  "url": "https://www.youtube.com/watch?v=VIDEO_ID",
+  "language": "en",  // optional
+  "format": "txt",   // optional
+  "model": "gpt-4o-mini-transcribe",  // optional
+  "outputPath": "./custom/path"  // optional
+}
+```
+
+**Example:**
+```bash
+curl -X POST http://localhost:8888/process \
+  -H "Content-Type: application/json" \
+  -d '{
+    "url": "https://www.youtube.com/watch?v=VIDEO_ID",
+    "language": "en",
+    "model": "gpt-4o-mini-transcribe"
+  }'
+```
+
+**Response:**
+```json
+{
+  "success": true,
+  "playlistTitle": null,
+  "totalVideos": 1,
+  "downloadedCount": 1,
+  "transcribedCount": 1,
+  "results": [
+    {
+      "title": "Video Title",
+      "downloadSuccess": true,
+      "audioPath": "./output/video.mp3",
+      "audioUrl": "/files/video.mp3",
+      "transcriptionSuccess": true,
+      "transcriptionPath": "./output/video.txt",
+      "transcriptionUrl": "/files/video.txt",
+      "text": "Transcription..."
+    }
+  ]
+}
+```
+
+---
+
+## Translation Endpoints
+
+### GET /languages
+Get available translation languages.
+
+**Response:**
+```json
+{
+  "languages": {
+    "en": "English",
+    "fr": "French",
+    "es": "Spanish",
+    "de": "German",
+    "zh": "Chinese",
+    "ja": "Japanese",
+    ...
+  }
+}
+```
+
+### POST /translate
+Translate text.
+
+**Body Parameters:**
+```json
+{
+  "text": "Text to translate",
+  "targetLang": "fr",  // required: target language code
+  "sourceLang": "en"   // optional: source language (auto-detect if not specified)
+}
+```
+
+**Example:**
+```bash
+curl -X POST http://localhost:8888/translate \
+  -H "Content-Type: application/json" \
+  -d '{
+    "text": "Hello, how are you?",
+    "targetLang": "fr"
+  }'
+```
+
+**Response:**
+```json
+{
+  "success": true,
+  "originalText": "Hello, how are you?",
+  "translatedText": "Bonjour, comment allez-vous ?",
+  "targetLanguage": "French",
+  "sourceLanguage": "auto-detected",
+  "chunks": 1
+}
+```
+
+### POST /translate-file
+Translate uploaded text files.
+
+**Form Data:**
+- `files`: Text file(s) (.txt, multiple files supported, max 50)
+- `targetLang`: Target language code (required)
+- `sourceLang`: Source language code (optional)
+- `outputPath`: Custom output directory (optional)
+
+**Example:**
+```bash
+curl -X POST http://localhost:8888/translate-file \
+  -F "files=@document.txt" \
+  -F "targetLang=fr" \
+  -F "sourceLang=en"
+```
+
+**Response:**
+```json
+{
+  "success": true,
+  "totalFiles": 1,
+  "successCount": 1,
+  "failCount": 0,
+  "results": [
+    {
+      "success": true,
+      "fileName": "document.txt",
+      "translationPath": "./output/document_fr.txt",
+      "translationUrl": "/files/document_fr.txt",
+      "translatedText": "Translated content..."
+    }
+  ]
+}
+```
+
+---
+
+## Summarization Endpoints
+
+### GET /summary-styles
+Get available summary styles.
+
+**Response:**
+```json
+{
+  "styles": {
+    "concise": "A brief summary capturing main points",
+    "detailed": "A comprehensive summary with nuances",
+    "bullet": "Key points as bullet points"
+  }
+}
+```
+
+### POST /summarize
+Summarize text using GPT-5.1.
+
+**Body Parameters:**
+```json
+{
+  "text": "Long text to summarize...",
+  "style": "concise",  // optional: concise (default), detailed, bullet
+  "language": "same",  // optional: 'same' (default) or language code
+  "model": "gpt-5.1"   // optional: default is gpt-5.1
+}
+```
+
+**Example:**
+```bash
+curl -X POST http://localhost:8888/summarize \
+  -H "Content-Type: application/json" \
+  -d '{
+    "text": "Long article content...",
+    "style": "bullet",
+    "language": "same"
+  }'
+```
+
+**Response:**
+```json
+{
+  "success": true,
+  "summary": "Summary content...",
+  "model": "gpt-5.1",
+  "style": "bullet",
+  "inputLength": 5000,
+  "chunks": 1
+}
+```
+
+### POST /summarize-file
+Summarize uploaded text files using GPT-5.1.
+
+**Form Data:**
+- `files`: Text file(s) (.txt, multiple files supported, max 50)
+- `style`: Summary style (optional, default: concise)
+- `language`: Output language (optional, default: same)
+- `model`: AI model (optional, default: gpt-5.1)
+- `outputPath`: Custom output directory (optional)
+
+**Example:**
+```bash
+curl -X POST http://localhost:8888/summarize-file \
+  -F "files=@article.txt" \
+  -F "style=detailed" \
+  -F "language=same"
+```
+
+**Response:**
+```json
+{
+  "success": true,
+  "totalFiles": 1,
+  "successCount": 1,
+  "failCount": 0,
+  "results": [
+    {
+      "success": true,
+      "fileName": "article.txt",
+      "summaryPath": "./output/article_summary.txt",
+      "summaryUrl": "/files/article_summary.txt",
+      "summary": "Summary content...",
+      "model": "gpt-5.1",
+      "chunks": 1
+    }
+  ]
+}
+```
+
+### GET /summarize-stream
+Full pipeline: Download -> Transcribe -> Summarize with SSE progress.
+
+**Query Parameters:**
+- `url` (required): YouTube URL
+- `style` (optional): Summary style (default: concise)
+- `language` (optional): Output language (default: same)
+- `model` (optional): Transcription model (default: gpt-4o-mini-transcribe)
+- `outputPath` (optional): Custom output directory
+
+**Example:**
+```bash
+curl "http://localhost:8888/summarize-stream?url=https://www.youtube.com/watch?v=VIDEO_ID&style=bullet&model=gpt-4o-mini-transcribe"
+```
+
+**SSE Events:**
+- `info`: Video information
+- `progress`: Progress updates (downloading, transcribing, or summarizing)
+- `video-complete`: Download complete
+- `transcribe-complete`: Transcription complete
+- `summarize-complete`: Summary complete
+- `complete`: All operations complete
+- `error`: Error occurred
+
+---
+
+## File Management
+
+### GET /files-list
+List all downloaded/generated files.
+
+**Example:**
+```bash
+curl http://localhost:8888/files-list
+```
+
+**Response:**
+```json
+{
+  "files": [
+    {
+      "name": "video.mp3",
+      "url": "/files/video.mp3",
+      "path": "./output/video.mp3"
+    },
+    {
+      "name": "video.txt",
+      "url": "/files/video.txt",
+      "path": "./output/video.txt"
+    }
+  ]
+}
+```
+
+### GET /files/:filename
+Serve a specific file.
+
+**Example:**
+```bash
+curl http://localhost:8888/files/video.mp3 --output video.mp3
+```
+
+---
+
+## Error Responses
+
+All endpoints return error responses in the following format:
+
+```json
+{
+  "error": "Error message describing what went wrong"
+}
+```
+
+Common HTTP status codes:
+- `400` - Bad Request (missing required parameters)
+- `500` - Internal Server Error (processing failed)
+
+---
+
+## Notes
+
+### Output Paths
+All endpoints that support `outputPath` parameter:
+- If not specified, files are saved to the default `OUTPUT_DIR` (./output)
+- If specified, files are saved to the custom path provided
+
+### Models
+- **Transcription**: Default is `gpt-4o-mini-transcribe` (cost-effective)
+- **Summarization**: Default is `gpt-5.1` (latest GPT model)
+- **Translation**: Uses `gpt-4o-mini` (hardcoded)
+
+### File Formats
+- **Audio**: MP3, WAV, M4A, OGG, FLAC
+- **Text**: TXT files
+- **Transcription outputs**: TXT, JSON, SRT, VTT (depending on model)
+
+### API Key
+Ensure `OPENAI_API_KEY` is set in your `.env` file for transcription, translation, and summarization features to work.
diff --git a/nul b/nul
new file mode 100644
index 0000000..42de59f
--- /dev/null
+++ b/nul
@@ -0,0 +1 @@
+/usr/bin/bash: line 1: del: command not found
diff --git a/public/app.js b/public/app.js
index c1cf74d..76c17b3 100644
--- a/public/app.js
+++ b/public/app.js
@@ -1,1129 +1,1129 @@
-// API Base URL
-const API_URL = '';
-
-// Tab switching
-document.querySelectorAll('.tab').forEach(tab => {
-  tab.addEventListener('click', () => {
-    document.querySelectorAll('.tab').forEach(t => t.classList.remove('active'));
-    document.querySelectorAll('.tab-content').forEach(c => c.classList.remove('active'));
-    tab.classList.add('active');
-    document.getElementById(tab.dataset.tab).classList.add('active');
-  });
-});
-
-// Helper: Show result
-function showResult(elementId, success, content) {
-  const el = document.getElementById(elementId);
-  el.className = `result show ${success ? 'success' : 'error'}`;
-  el.innerHTML = content;
-}
-
-// Helper: Set loading state
-function setLoading(button, loading) {
-  button.disabled = loading;
-  button.classList.toggle('loading', loading);
-}
-
-// Format seconds to MM:SS or HH:MM:SS
-function formatTime(seconds) {
-  if (!seconds || seconds < 0) return '--:--';
-  const hrs = Math.floor(seconds / 3600);
-  const mins = Math.floor((seconds % 3600) / 60);
-  const secs = Math.floor(seconds % 60);
-  if (hrs > 0) {
-    return `${hrs}:${String(mins).padStart(2, '0')}:${String(secs).padStart(2, '0')}`;
-  }
-  return `${mins}:${String(secs).padStart(2, '0')}`;
-}
-
-// Format file size
-function formatSize(bytes) {
-  if (!bytes) return '';
-  const units = ['B', 'KB', 'MB', 'GB'];
-  let i = 0;
-  while (bytes >= 1024 && i < units.length - 1) {
-    bytes /= 1024;
-    i++;
-  }
-  return `${bytes.toFixed(1)} ${units[i]}`;
-}
-
-// ==================== DOWNLOAD TAB ====================
-
-const progressContainer = document.getElementById('download-progress');
-const progressFill = document.getElementById('progress-fill');
-const progressPercent = document.getElementById('progress-percent');
-const progressTitle = document.getElementById('progress-title');
-const progressEta = document.getElementById('progress-eta');
-const progressInfo = document.getElementById('progress-info');
-const progressSpeed = document.getElementById('progress-speed');
-const progressCurrent = document.getElementById('progress-current');
-
-function updateDownloadProgress(data) {
-  progressFill.style.width = `${data.percent}%`;
-  progressPercent.textContent = `${data.percent}%`;
-
-  if (data.totalVideos > 1) {
-    progressInfo.textContent = `Video ${data.currentVideo}/${data.totalVideos}`;
-  } else {
-    progressInfo.textContent = '';
-  }
-
-  if (data.speed) progressSpeed.textContent = data.speed;
-  if (data.estimatedRemaining) {
-    progressEta.textContent = `ETA: ${formatTime(data.estimatedRemaining)}`;
-  } else if (data.eta) {
-    progressEta.textContent = `ETA: ${data.eta}`;
-  }
-  if (data.title) {
-    progressCurrent.innerHTML = `Downloading: <span class="video-title">${data.title}</span>`;
-  }
-}
-
-function resetDownloadProgress() {
-  progressFill.style.width = '0%';
-  progressPercent.textContent = '0%';
-  progressTitle.textContent = 'Downloading...';
-  progressEta.textContent = '';
-  progressInfo.textContent = '';
-  progressSpeed.textContent = '';
-  progressCurrent.textContent = '';
-}
-
-document.getElementById('download-form').addEventListener('submit', async (e) => {
-  e.preventDefault();
-  const button = e.target.querySelector('button[type="submit"]');
-  const url = document.getElementById('download-url').value;
-  const resultDiv = document.getElementById('download-result');
-
-  setLoading(button, true);
-  resetDownloadProgress();
-  progressContainer.style.display = 'block';
-  resultDiv.classList.remove('show');
-
-  const eventSource = new EventSource(`${API_URL}/download-stream?url=${encodeURIComponent(url)}`);
-
-  eventSource.addEventListener('status', (e) => {
-    progressTitle.textContent = JSON.parse(e.data).message;
-  });
-
-  eventSource.addEventListener('info', (e) => {
-    const data = JSON.parse(e.data);
-    progressTitle.textContent = data.totalVideos > 1
-      ? `Downloading playlist: ${data.playlistTitle} (${data.totalVideos} videos)`
-      : `Downloading: ${data.title}`;
-  });
-
-  eventSource.addEventListener('progress', (e) => updateDownloadProgress(JSON.parse(e.data)));
-
-  eventSource.addEventListener('video-complete', (e) => {
-    const data = JSON.parse(e.data);
-    progressCurrent.innerHTML = `Completed: <span class="video-title">${data.title}</span> (${data.videosCompleted}/${data.totalVideos})`;
-  });
-
-  eventSource.addEventListener('complete', (e) => {
-    const data = JSON.parse(e.data);
-    eventSource.close();
-    progressFill.style.width = '100%';
-    progressPercent.textContent = '100%';
-    progressTitle.textContent = 'Download Complete!';
-    progressEta.textContent = `Total: ${formatTime(data.totalTime)}`;
-
-    showResult('download-result', true, `
-      <h3>Download Complete!</h3>
-      <p>${data.successCount}/${data.totalVideos} videos downloaded</p>
-      ${data.playlistTitle ? `<p>Playlist: ${data.playlistTitle}</p>` : ''}
-      <ul>${data.videos.map(v => `
-        <li>
-          <span class="${v.success ? 'icon-success' : 'icon-error'}">${v.success ? '✓' : '✗'}</span>
-          ${v.title}
-          ${v.success && v.fileUrl ? `<a href="${v.fileUrl}" target="_blank">Download</a>` : ''}
-          ${v.error ? `<small>(${v.error})</small>` : ''}
-        </li>
-      `).join('')}</ul>
-    `);
-    setLoading(button, false);
-  });
-
-  eventSource.addEventListener('error', (e) => {
-    let errorMsg = 'Download failed';
-    try { errorMsg = JSON.parse(e.data).message || errorMsg; } catch {}
-    eventSource.close();
-    progressContainer.style.display = 'none';
-    showResult('download-result', false, `<h3>Error</h3><p>${errorMsg}</p>`);
-    setLoading(button, false);
-  });
-
-  eventSource.onerror = () => {
-    eventSource.close();
-    progressContainer.style.display = 'none';
-    showResult('download-result', false, `<h3>Error</h3><p>Connection lost</p>`);
-    setLoading(button, false);
-  };
-});
-
-// ==================== CONVERT TAB (Video to MP3) ====================
-
-let convertSelectedFiles = [];
-const convertDropZone = document.getElementById('convert-drop-zone');
-const convertFileInput = document.getElementById('convert-file-input');
-const convertSelectedFilesDiv = document.getElementById('convert-selected-files');
-const convertFilesList = document.getElementById('convert-files-list');
-const convertBtn = document.getElementById('convert-btn');
-const convertClearFilesBtn = document.getElementById('convert-clear-files');
-
-function updateConvertFilesList() {
-  if (convertSelectedFiles.length === 0) {
-    convertSelectedFilesDiv.style.display = 'none';
-    convertBtn.disabled = true;
-    return;
-  }
-
-  convertSelectedFilesDiv.style.display = 'block';
-  convertBtn.disabled = false;
-
-  convertFilesList.innerHTML = convertSelectedFiles.map((file, index) => `
-    <li>
-      <span class="file-name">${file.name}</span>
-      <span class="file-size">${formatSize(file.size)}</span>
-      <button type="button" class="remove-file" data-index="${index}">×</button>
-    </li>
-  `).join('');
-
-  // Add remove handlers
-  convertFilesList.querySelectorAll('.remove-file').forEach(btn => {
-    btn.addEventListener('click', () => {
-      convertSelectedFiles.splice(parseInt(btn.dataset.index), 1);
-      updateConvertFilesList();
-    });
-  });
-}
-
-function addConvertFiles(files) {
-  const videoAudioFiles = Array.from(files).filter(f =>
-    f.type.startsWith('video/') || f.type.startsWith('audio/') ||
-    f.name.match(/\.(mp4|avi|mkv|mov|m4a|wav|flac|ogg|webm|wmv|flv)$/i)
-  );
-  convertSelectedFiles = [...convertSelectedFiles, ...videoAudioFiles];
-  updateConvertFilesList();
-}
-
-// Drag & Drop events for convert
-convertDropZone.addEventListener('click', () => convertFileInput.click());
-
-convertDropZone.addEventListener('dragover', (e) => {
-  e.preventDefault();
-  convertDropZone.classList.add('drag-over');
-});
-
-convertDropZone.addEventListener('dragleave', () => {
-  convertDropZone.classList.remove('drag-over');
-});
-
-convertDropZone.addEventListener('drop', (e) => {
-  e.preventDefault();
-  convertDropZone.classList.remove('drag-over');
-  addConvertFiles(e.dataTransfer.files);
-});
-
-convertFileInput.addEventListener('change', () => {
-  addConvertFiles(convertFileInput.files);
-  convertFileInput.value = '';
-});
-
-convertClearFilesBtn.addEventListener('click', () => {
-  convertSelectedFiles = [];
-  updateConvertFilesList();
-});
-
-// Convert form submit
-document.getElementById('convert-form').addEventListener('submit', async (e) => {
-  e.preventDefault();
-  if (convertSelectedFiles.length === 0) return;
-
-  const button = convertBtn;
-  const bitrate = document.getElementById('convert-bitrate').value;
-  const quality = document.getElementById('convert-quality').value;
-
-  const convertProgress = document.getElementById('convert-progress');
-  const convertProgressFill = document.getElementById('convert-progress-fill');
-  const convertProgressTitle = document.getElementById('convert-progress-title');
-  const convertProgressPercent = document.getElementById('convert-progress-percent');
-  const convertProgressInfo = document.getElementById('convert-progress-info');
-  const convertProgressCurrent = document.getElementById('convert-progress-current');
-
-  setLoading(button, true);
-  convertProgress.style.display = 'block';
-  convertProgressFill.style.width = '0%';
-  convertProgressTitle.textContent = 'Converting to MP3...';
-  convertProgressPercent.textContent = '0%';
-  convertProgressInfo.textContent = `0/${convertSelectedFiles.length} files`;
-  document.getElementById('convert-result').classList.remove('show');
-
-  const formData = new FormData();
-  convertSelectedFiles.forEach(file => formData.append('files', file));
-  formData.append('bitrate', bitrate);
-  formData.append('quality', quality);
-
-  try {
-    const response = await fetch(`${API_URL}/convert-to-mp3`, {
-      method: 'POST',
-      body: formData
-    });
-
-    const data = await response.json();
-
-    if (!response.ok) throw new Error(data.error || 'Conversion failed');
-
-    convertProgressFill.style.width = '100%';
-    convertProgressPercent.textContent = '100%';
-    convertProgressTitle.textContent = 'Conversion Complete!';
-    convertProgressInfo.textContent = `${data.successCount}/${data.totalFiles} files`;
-
-    showResult('convert-result', true, `
-      <h3>Conversion Complete!</h3>
-      <p>${data.successCount}/${data.totalFiles} files converted to MP3</p>
-      <div class="file-results">
-        ${data.results.map(r => r.success ? `
-          <div class="file-result success">
-            <div class="file-info">
-              <strong>${r.fileName}</strong>
-              <span class="file-size">${r.size}</span>
-            </div>
-            <a href="${r.outputUrl}" download class="btn btn-small btn-primary">Download MP3</a>
-          </div>
-        ` : `
-          <div class="file-result error">
-            <strong>${r.fileName}</strong>
-            <span class="error-msg">${r.error}</span>
-          </div>
-        `).join('')}
-      </div>
-    `);
-
-    // Clear selected files after successful conversion
-    convertSelectedFiles = [];
-    updateConvertFilesList();
-
-  } catch (error) {
-    showResult('convert-result', false, `<h3>Error</h3><p>${error.message}</p>`);
-  } finally {
-    setLoading(button, false);
-    setTimeout(() => {
-      convertProgress.style.display = 'none';
-    }, 1000);
-  }
-});
-
-// ==================== TRANSCRIBE TAB (Drag & Drop) ====================
-
-let selectedFiles = [];
-const dropZone = document.getElementById('drop-zone');
-const fileInput = document.getElementById('file-input');
-const selectedFilesDiv = document.getElementById('selected-files');
-const filesList = document.getElementById('files-list');
-const transcribeBtn = document.getElementById('transcribe-btn');
-const clearFilesBtn = document.getElementById('clear-files');
-
-function updateFilesList() {
-  if (selectedFiles.length === 0) {
-    selectedFilesDiv.style.display = 'none';
-    transcribeBtn.disabled = true;
-    return;
-  }
-
-  selectedFilesDiv.style.display = 'block';
-  transcribeBtn.disabled = false;
-
-  filesList.innerHTML = selectedFiles.map((file, index) => `
-    <li>
-      <span class="file-name">${file.name}</span>
-      <span class="file-size">${formatSize(file.size)}</span>
-      <button type="button" class="remove-file" data-index="${index}">×</button>
-    </li>
-  `).join('');
-
-  // Add remove handlers
-  filesList.querySelectorAll('.remove-file').forEach(btn => {
-    btn.addEventListener('click', () => {
-      selectedFiles.splice(parseInt(btn.dataset.index), 1);
-      updateFilesList();
-    });
-  });
-}
-
-function addFiles(files) {
-  const audioFiles = Array.from(files).filter(f =>
-    f.type.startsWith('audio/') || f.name.match(/\.(mp3|wav|m4a|ogg|flac)$/i)
-  );
-  selectedFiles = [...selectedFiles, ...audioFiles];
-  updateFilesList();
-}
-
-// Drag & Drop events
-dropZone.addEventListener('click', () => fileInput.click());
-
-dropZone.addEventListener('dragover', (e) => {
-  e.preventDefault();
-  dropZone.classList.add('drag-over');
-});
-
-dropZone.addEventListener('dragleave', () => {
-  dropZone.classList.remove('drag-over');
-});
-
-dropZone.addEventListener('drop', (e) => {
-  e.preventDefault();
-  dropZone.classList.remove('drag-over');
-  addFiles(e.dataTransfer.files);
-});
-
-fileInput.addEventListener('change', () => {
-  addFiles(fileInput.files);
-  fileInput.value = '';
-});
-
-clearFilesBtn.addEventListener('click', () => {
-  selectedFiles = [];
-  updateFilesList();
-});
-
-// Transcribe form submit
-document.getElementById('transcribe-form').addEventListener('submit', async (e) => {
-  e.preventDefault();
-  if (selectedFiles.length === 0) return;
-
-  const button = transcribeBtn;
-  const language = document.getElementById('transcribe-lang').value;
-  const model = document.getElementById('transcribe-model').value;
-
-  const transcribeProgress = document.getElementById('transcribe-progress');
-  const transcribeProgressFill = document.getElementById('transcribe-progress-fill');
-  const transcribeProgressTitle = document.getElementById('transcribe-progress-title');
-  const transcribeProgressPercent = document.getElementById('transcribe-progress-percent');
-  const transcribeProgressInfo = document.getElementById('transcribe-progress-info');
-  const transcribeProgressCurrent = document.getElementById('transcribe-progress-current');
-
-  setLoading(button, true);
-  transcribeProgress.style.display = 'block';
-  transcribeProgressFill.style.width = '0%';
-  transcribeProgressTitle.textContent = 'Uploading and transcribing...';
-  transcribeProgressPercent.textContent = '0%';
-  transcribeProgressInfo.textContent = `0/${selectedFiles.length} files`;
-  document.getElementById('transcribe-result').classList.remove('show');
-
-  const formData = new FormData();
-  selectedFiles.forEach(file => formData.append('files', file));
-  if (language) formData.append('language', language);
-  formData.append('model', model);
-
-  try {
-    const response = await fetch(`${API_URL}/upload-transcribe`, {
-      method: 'POST',
-      body: formData
-    });
-
-    const data = await response.json();
-
-    if (!response.ok) throw new Error(data.error || 'Transcription failed');
-
-    transcribeProgressFill.style.width = '100%';
-    transcribeProgressPercent.textContent = '100%';
-    transcribeProgressTitle.textContent = 'Transcription Complete!';
-    transcribeProgressInfo.textContent = `${data.successCount}/${data.totalFiles} files`;
-
-    showResult('transcribe-result', true, `
-      <h3>Transcription Complete!</h3>
-      <p>${data.successCount}/${data.totalFiles} files transcribed</p>
-      <ul>${data.results.map(r => `
-        <li>
-          <span class="${r.success ? 'icon-success' : 'icon-error'}">${r.success ? '✓' : '✗'}</span>
-          ${r.fileName}
-          ${r.success && r.transcriptionUrl ? `<a href="${r.transcriptionUrl}" target="_blank">View</a>` : ''}
-          ${r.error ? `<small>(${r.error})</small>` : ''}
-        </li>
-      `).join('')}</ul>
-      ${data.results[0]?.text ? `
-        <h4>Preview (first file):</h4>
-        <div class="preview">${data.results[0].text.substring(0, 1000)}${data.results[0].text.length > 1000 ? '...' : ''}</div>
-      ` : ''}
-    `);
-
-    selectedFiles = [];
-    updateFilesList();
-
-  } catch (error) {
-    transcribeProgress.style.display = 'none';
-    showResult('transcribe-result', false, `<h3>Error</h3><p>${error.message}</p>`);
-  } finally {
-    setLoading(button, false);
-  }
-});
-
-// ==================== PROCESS TAB (Download + Transcribe) ====================
-
-const processProgress = document.getElementById('process-progress');
-const processProgressFill = document.getElementById('process-progress-fill');
-const processProgressTitle = document.getElementById('process-progress-title');
-const processProgressPercent = document.getElementById('process-progress-percent');
-const processProgressPhase = document.getElementById('process-progress-phase');
-const processProgressSpeed = document.getElementById('process-progress-speed');
-const processProgressCurrent = document.getElementById('process-progress-current');
-const processProgressEta = document.getElementById('process-progress-eta');
-
-function resetProcessProgress() {
-  processProgressFill.style.width = '0%';
-  processProgressPercent.textContent = '0%';
-  processProgressTitle.textContent = 'Processing...';
-  processProgressPhase.textContent = '';
-  processProgressSpeed.textContent = '';
-  processProgressCurrent.textContent = '';
-  processProgressEta.textContent = '';
-}
-
-document.getElementById('process-form').addEventListener('submit', async (e) => {
-  e.preventDefault();
-  const button = e.target.querySelector('button[type="submit"]');
-  const url = document.getElementById('process-url').value;
-  const language = document.getElementById('process-lang').value;
-  const model = document.getElementById('process-model').value;
-  const resultDiv = document.getElementById('process-result');
-
-  setLoading(button, true);
-  resetProcessProgress();
-  processProgress.style.display = 'block';
-  resultDiv.classList.remove('show');
-
-  const params = new URLSearchParams({ url });
-  if (language) params.append('language', language);
-  params.append('model', model);
-
-  const eventSource = new EventSource(`${API_URL}/process-stream?${params}`);
-
-  eventSource.addEventListener('status', (e) => {
-    const data = JSON.parse(e.data);
-    processProgressTitle.textContent = data.message;
-    if (data.phase === 'transcribing') {
-      processProgressPhase.textContent = 'Transcribing';
-    }
-  });
-
-  eventSource.addEventListener('info', (e) => {
-    const data = JSON.parse(e.data);
-    processProgressTitle.textContent = data.totalVideos > 1
-      ? `Processing playlist: ${data.playlistTitle} (${data.totalVideos} videos)`
-      : `Processing: ${data.title}`;
-  });
-
-  eventSource.addEventListener('progress', (e) => {
-    const data = JSON.parse(e.data);
-    processProgressFill.style.width = `${data.percent}%`;
-    processProgressPercent.textContent = `${Math.round(data.percent)}%`;
-    processProgressPhase.textContent = data.phaseLabel || '';
-    if (data.speed) processProgressSpeed.textContent = data.speed;
-    if (data.title) {
-      processProgressCurrent.innerHTML = `${data.phaseLabel}: <span class="video-title">${data.title}</span>`;
-    }
-    if (data.totalVideos > 1) {
-      processProgressCurrent.innerHTML += ` (${data.currentVideo}/${data.totalVideos})`;
-    }
-  });
-
-  eventSource.addEventListener('video-complete', (e) => {
-    const data = JSON.parse(e.data);
-    processProgressCurrent.innerHTML = `Downloaded: <span class="video-title">${data.title}</span>`;
-  });
-
-  eventSource.addEventListener('transcribe-complete', (e) => {
-    const data = JSON.parse(e.data);
-    processProgressCurrent.innerHTML = `Transcribed: <span class="video-title">${data.title}</span> (${data.videosCompleted}/${data.totalFiles})`;
-  });
-
-  eventSource.addEventListener('complete', (e) => {
-    const data = JSON.parse(e.data);
-    eventSource.close();
-    processProgressFill.style.width = '100%';
-    processProgressPercent.textContent = '100%';
-    processProgressTitle.textContent = 'Processing Complete!';
-    processProgressPhase.textContent = '';
-    processProgressEta.textContent = `Total: ${formatTime(data.totalTime)}`;
-
-    showResult('process-result', true, `
-      <h3>Processing Complete!</h3>
-      ${data.playlistTitle ? `<p>Playlist: ${data.playlistTitle}</p>` : ''}
-      <p>Downloaded: ${data.downloadedCount}/${data.totalVideos}</p>
-      <p>Transcribed: ${data.transcribedCount}/${data.totalVideos}</p>
-      <ul>${data.results.map(r => `
-        <li>
-          <span class="${r.transcriptionSuccess ? 'icon-success' : 'icon-error'}">${r.transcriptionSuccess ? '✓' : '✗'}</span>
-          ${r.title}
-          ${r.audioUrl ? `<a href="${r.audioUrl}" target="_blank">MP3</a>` : ''}
-          ${r.transcriptionUrl ? `<a href="${r.transcriptionUrl}" target="_blank">TXT</a>` : ''}
-          ${r.error ? `<small>(${r.error})</small>` : ''}
-        </li>
-      `).join('')}</ul>
-      ${data.results[0]?.text ? `
-        <h4>Preview (first file):</h4>
-        <div class="preview">${data.results[0].text.substring(0, 1000)}${data.results[0].text.length > 1000 ? '...' : ''}</div>
-      ` : ''}
-    `);
-    setLoading(button, false);
-  });
-
-  eventSource.addEventListener('error', (e) => {
-    let errorMsg = 'Processing failed';
-    try { errorMsg = JSON.parse(e.data).message || errorMsg; } catch {}
-    eventSource.close();
-    processProgress.style.display = 'none';
-    showResult('process-result', false, `<h3>Error</h3><p>${errorMsg}</p>`);
-    setLoading(button, false);
-  });
-
-  eventSource.onerror = () => {
-    eventSource.close();
-    processProgress.style.display = 'none';
-    showResult('process-result', false, `<h3>Error</h3><p>Connection lost</p>`);
-    setLoading(button, false);
-  };
-});
-
-// ==================== TRANSLATE CHECKBOXES (Transcribe & Process tabs) ====================
-
-// Transcribe tab checkbox
-const transcribeTranslateCheckbox = document.getElementById('transcribe-translate');
-const transcribeTranslateLang = document.getElementById('transcribe-translate-lang');
-
-transcribeTranslateCheckbox.addEventListener('change', () => {
-  transcribeTranslateLang.disabled = !transcribeTranslateCheckbox.checked;
-});
-
-// Process tab checkbox
-const processTranslateCheckbox = document.getElementById('process-translate');
-const processTranslateLang = document.getElementById('process-translate-lang');
-
-processTranslateCheckbox.addEventListener('change', () => {
-  processTranslateLang.disabled = !processTranslateCheckbox.checked;
-});
-
-// ==================== TRANSLATE TAB ====================
-
-// Mode switching
-const translateModeBtns = document.querySelectorAll('.mode-btn');
-const translateTextMode = document.getElementById('translate-text-mode');
-const translateFileMode = document.getElementById('translate-file-mode');
-
-translateModeBtns.forEach(btn => {
-  btn.addEventListener('click', () => {
-    translateModeBtns.forEach(b => b.classList.remove('active'));
-    btn.classList.add('active');
-
-    if (btn.dataset.mode === 'text') {
-      translateTextMode.style.display = 'block';
-      translateFileMode.style.display = 'none';
-    } else {
-      translateTextMode.style.display = 'none';
-      translateFileMode.style.display = 'block';
-    }
-  });
-});
-
-// Text translation form
-document.getElementById('translate-text-form').addEventListener('submit', async (e) => {
-  e.preventDefault();
-  const button = document.getElementById('translate-text-btn');
-  const text = document.getElementById('translate-input').value;
-  const sourceLang = document.getElementById('translate-source').value;
-  const targetLang = document.getElementById('translate-target').value;
-
-  if (!text.trim()) {
-    showResult('translate-text-result', false, '<h3>Error</h3><p>Please enter text to translate</p>');
-    return;
-  }
-
-  setLoading(button, true);
-  document.getElementById('translate-text-result').classList.remove('show');
-
-  try {
-    const response = await fetch(`${API_URL}/translate`, {
-      method: 'POST',
-      headers: { 'Content-Type': 'application/json' },
-      body: JSON.stringify({ text, targetLang, sourceLang: sourceLang || null })
-    });
-
-    const data = await response.json();
-    if (!response.ok) throw new Error(data.error || 'Translation failed');
-
-    showResult('translate-text-result', true, `
-      <h3>Translation Complete!</h3>
-      <p><strong>From:</strong> ${data.sourceLanguage} <strong>To:</strong> ${data.targetLanguage}</p>
-      <div class="translation-output">${data.translatedText}</div>
-    `);
-  } catch (error) {
-    showResult('translate-text-result', false, `<h3>Error</h3><p>${error.message}</p>`);
-  } finally {
-    setLoading(button, false);
-  }
-});
-
-// File translation - Drag & Drop
-let translateSelectedFiles = [];
-const translateDropZone = document.getElementById('translate-drop-zone');
-const translateFileInput = document.getElementById('translate-file-input');
-const translateSelectedFilesDiv = document.getElementById('translate-selected-files');
-const translateFilesList = document.getElementById('translate-files-list');
-const translateFileBtn = document.getElementById('translate-file-btn');
-const translateClearFilesBtn = document.getElementById('translate-clear-files');
-
-function updateTranslateFilesList() {
-  if (translateSelectedFiles.length === 0) {
-    translateSelectedFilesDiv.style.display = 'none';
-    translateFileBtn.disabled = true;
-    return;
-  }
-
-  translateSelectedFilesDiv.style.display = 'block';
-  translateFileBtn.disabled = false;
-
-  translateFilesList.innerHTML = translateSelectedFiles.map((file, index) => `
-    <li>
-      <span class="file-name">${file.name}</span>
-      <span class="file-size">${formatSize(file.size)}</span>
-      <button type="button" class="remove-file" data-index="${index}">x</button>
-    </li>
-  `).join('');
-
-  translateFilesList.querySelectorAll('.remove-file').forEach(btn => {
-    btn.addEventListener('click', () => {
-      translateSelectedFiles.splice(parseInt(btn.dataset.index), 1);
-      updateTranslateFilesList();
-    });
-  });
-}
-
-function addTranslateFiles(files) {
-  const textFiles = Array.from(files).filter(f =>
-    f.type === 'text/plain' || f.name.endsWith('.txt')
-  );
-  translateSelectedFiles = [...translateSelectedFiles, ...textFiles];
-  updateTranslateFilesList();
-}
-
-translateDropZone.addEventListener('click', () => translateFileInput.click());
-
-translateDropZone.addEventListener('dragover', (e) => {
-  e.preventDefault();
-  translateDropZone.classList.add('drag-over');
-});
-
-translateDropZone.addEventListener('dragleave', () => {
-  translateDropZone.classList.remove('drag-over');
-});
-
-translateDropZone.addEventListener('drop', (e) => {
-  e.preventDefault();
-  translateDropZone.classList.remove('drag-over');
-  addTranslateFiles(e.dataTransfer.files);
-});
-
-translateFileInput.addEventListener('change', () => {
-  addTranslateFiles(translateFileInput.files);
-  translateFileInput.value = '';
-});
-
-translateClearFilesBtn.addEventListener('click', () => {
-  translateSelectedFiles = [];
-  updateTranslateFilesList();
-});
-
-// File translation form submit
-document.getElementById('translate-file-form').addEventListener('submit', async (e) => {
-  e.preventDefault();
-  if (translateSelectedFiles.length === 0) return;
-
-  const button = translateFileBtn;
-  const sourceLang = document.getElementById('translate-file-source').value;
-  const targetLang = document.getElementById('translate-file-target').value;
-
-  setLoading(button, true);
-  document.getElementById('translate-file-result').classList.remove('show');
-
-  const formData = new FormData();
-  translateSelectedFiles.forEach(file => formData.append('files', file));
-  formData.append('targetLang', targetLang);
-  if (sourceLang) formData.append('sourceLang', sourceLang);
-
-  try {
-    const response = await fetch(`${API_URL}/translate-file`, {
-      method: 'POST',
-      body: formData
-    });
-
-    const data = await response.json();
-    if (!response.ok) throw new Error(data.error || 'Translation failed');
-
-    showResult('translate-file-result', true, `
-      <h3>Translation Complete!</h3>
-      <p>${data.successCount}/${data.totalFiles} files translated</p>
-      <ul>${data.results.map(r => `
-        <li>
-          <span class="${r.success ? 'icon-success' : 'icon-error'}">${r.success ? '✓' : '✗'}</span>
-          ${r.fileName || r.originalPath}
-          ${r.success && r.translationUrl ? `<a href="${r.translationUrl}" target="_blank">View</a>` : ''}
-          ${r.error ? `<small>(${r.error})</small>` : ''}
-        </li>
-      `).join('')}</ul>
-      ${data.results[0]?.translatedText ? `
-        <h4>Preview (first file):</h4>
-        <div class="translation-output">${data.results[0].translatedText.substring(0, 1000)}${data.results[0].translatedText.length > 1000 ? '...' : ''}</div>
-      ` : ''}
-    `);
-
-    translateSelectedFiles = [];
-    updateTranslateFilesList();
-
-  } catch (error) {
-    showResult('translate-file-result', false, `<h3>Error</h3><p>${error.message}</p>`);
-  } finally {
-    setLoading(button, false);
-  }
-});
-
-// ==================== SUMMARIZE TAB ====================
-
-// Mode switching
-const summarizeModeBtns = document.querySelectorAll('.summarize-mode-selector .mode-btn');
-const summarizeTextMode = document.getElementById('summarize-text-mode');
-const summarizeFileMode = document.getElementById('summarize-file-mode');
-
-const summarizeLinkMode = document.getElementById('summarize-link-mode');
-
-summarizeModeBtns.forEach(btn => {
-  btn.addEventListener('click', () => {
-    summarizeModeBtns.forEach(b => b.classList.remove('active'));
-    btn.classList.add('active');
-
-    summarizeTextMode.style.display = 'none';
-    summarizeFileMode.style.display = 'none';
-    if (summarizeLinkMode) summarizeLinkMode.style.display = 'none';
-
-    if (btn.dataset.mode === 'text') {
-      summarizeTextMode.style.display = 'block';
-    } else if (btn.dataset.mode === 'file') {
-      summarizeFileMode.style.display = 'block';
-    } else if (btn.dataset.mode === 'link' && summarizeLinkMode) {
-      summarizeLinkMode.style.display = 'block';
-    }
-  });
-});
-
-// Text summarization form
-document.getElementById('summarize-text-form').addEventListener('submit', async (e) => {
-  e.preventDefault();
-  const button = document.getElementById('summarize-text-btn');
-  const text = document.getElementById('summarize-input').value;
-  const style = document.getElementById('summarize-style').value;
-  const language = document.getElementById('summarize-language').value;
-
-  if (!text.trim()) {
-    showResult('summarize-text-result', false, '<h3>Error</h3><p>Please enter text to summarize</p>');
-    return;
-  }
-
-  setLoading(button, true);
-  document.getElementById('summarize-text-result').classList.remove('show');
-
-  try {
-    const response = await fetch(`${API_URL}/summarize`, {
-      method: 'POST',
-      headers: { 'Content-Type': 'application/json' },
-      body: JSON.stringify({ text, style, language })
-    });
-
-    const data = await response.json();
-    if (!response.ok) throw new Error(data.error || 'Summarization failed');
-
-    showResult('summarize-text-result', true, `
-      <h3>Summary Complete!</h3>
-      <p><strong>Model:</strong> ${data.model} | <strong>Style:</strong> ${data.style} | <strong>Chunks:</strong> ${data.chunks}</p>
-      <div class="summary-output">${data.summary}</div>
-    `);
-  } catch (error) {
-    showResult('summarize-text-result', false, `<h3>Error</h3><p>${error.message}</p>`);
-  } finally {
-    setLoading(button, false);
-  }
-});
-
-// File summarization - Drag & Drop
-let summarizeSelectedFiles = [];
-const summarizeDropZone = document.getElementById('summarize-drop-zone');
-const summarizeFileInput = document.getElementById('summarize-file-input');
-const summarizeSelectedFilesDiv = document.getElementById('summarize-selected-files');
-const summarizeFilesList = document.getElementById('summarize-files-list');
-const summarizeFileBtn = document.getElementById('summarize-file-btn');
-const summarizeClearFilesBtn = document.getElementById('summarize-clear-files');
-
-function updateSummarizeFilesList() {
-  if (!summarizeSelectedFilesDiv || !summarizeFileBtn || !summarizeFilesList) return;
-
-  if (summarizeSelectedFiles.length === 0) {
-    summarizeSelectedFilesDiv.style.display = 'none';
-    summarizeFileBtn.disabled = true;
-    return;
-  }
-
-  summarizeSelectedFilesDiv.style.display = 'block';
-  summarizeFileBtn.disabled = false;
-
-  summarizeFilesList.innerHTML = summarizeSelectedFiles.map((file, index) => `
-    <li>
-      <span class="file-name">${file.name}</span>
-      <span class="file-size">${formatSize(file.size)}</span>
-      <button type="button" class="remove-file" data-index="${index}">x</button>
-    </li>
-  `).join('');
-
-  summarizeFilesList.querySelectorAll('.remove-file').forEach(btn => {
-    btn.addEventListener('click', () => {
-      summarizeSelectedFiles.splice(parseInt(btn.dataset.index), 1);
-      updateSummarizeFilesList();
-    });
-  });
-}
-
-function addSummarizeFiles(files) {
-  console.log('Adding files:', files);
-  const textFiles = Array.from(files).filter(f =>
-    f.type === 'text/plain' || f.name.endsWith('.txt')
-  );
-  console.log('Filtered text files:', textFiles);
-  summarizeSelectedFiles = [...summarizeSelectedFiles, ...textFiles];
-  updateSummarizeFilesList();
-}
-
-if (summarizeDropZone) {
-  summarizeDropZone.addEventListener('click', () => {
-    console.log('Drop zone clicked');
-    summarizeFileInput.click();
-  });
-
-  summarizeDropZone.addEventListener('dragover', (e) => {
-    e.preventDefault();
-    e.stopPropagation();
-    summarizeDropZone.classList.add('drag-over');
-  });
-
-  summarizeDropZone.addEventListener('dragleave', (e) => {
-    e.preventDefault();
-    e.stopPropagation();
-    summarizeDropZone.classList.remove('drag-over');
-  });
-
-  summarizeDropZone.addEventListener('drop', (e) => {
-    e.preventDefault();
-    e.stopPropagation();
-    console.log('Files dropped:', e.dataTransfer.files);
-    summarizeDropZone.classList.remove('drag-over');
-    addSummarizeFiles(e.dataTransfer.files);
-  });
-}
-
-if (summarizeFileInput) {
-  summarizeFileInput.addEventListener('change', () => {
-    console.log('File input changed:', summarizeFileInput.files);
-    addSummarizeFiles(summarizeFileInput.files);
-    summarizeFileInput.value = '';
-  });
-}
-
-if (summarizeClearFilesBtn) {
-  summarizeClearFilesBtn.addEventListener('click', () => {
-    summarizeSelectedFiles = [];
-    updateSummarizeFilesList();
-  });
-}
-
-// File summarization form submit
-document.getElementById('summarize-file-form').addEventListener('submit', async (e) => {
-  e.preventDefault();
-  if (summarizeSelectedFiles.length === 0) return;
-
-  const button = summarizeFileBtn;
-  const style = document.getElementById('summarize-file-style').value;
-  const language = document.getElementById('summarize-file-language').value;
-
-  setLoading(button, true);
-  document.getElementById('summarize-file-result').classList.remove('show');
-
-  const formData = new FormData();
-  summarizeSelectedFiles.forEach(file => formData.append('files', file));
-  formData.append('style', style);
-  formData.append('language', language);
-
-  try {
-    const response = await fetch(`${API_URL}/summarize-file`, {
-      method: 'POST',
-      body: formData
-    });
-
-    const data = await response.json();
-    if (!response.ok) throw new Error(data.error || 'Summarization failed');
-
-    showResult('summarize-file-result', true, `
-      <h3>Summarization Complete!</h3>
-      <p>${data.successCount}/${data.totalFiles} files summarized</p>
-      <ul>${data.results.map(r => `
-        <li>
-          <span class="${r.success ? 'icon-success' : 'icon-error'}">${r.success ? '✓' : '✗'}</span>
-          ${r.fileName || r.filePath}
-          ${r.success && r.summaryUrl ? `<a href="${r.summaryUrl}" target="_blank">View</a>` : ''}
-          ${r.error ? `<small>(${r.error})</small>` : ''}
-        </li>
-      `).join('')}</ul>
-      ${data.results[0]?.summary ? `
-        <h4>Preview (first file):</h4>
-        <div class="summary-output">${data.results[0].summary.substring(0, 1000)}${data.results[0].summary.length > 1000 ? '...' : ''}</div>
-      ` : ''}
-    `);
-
-    summarizeSelectedFiles = [];
-    updateSummarizeFilesList();
-
-  } catch (error) {
-    showResult('summarize-file-result', false, `<h3>Error</h3><p>${error.message}</p>`);
-  } finally {
-    setLoading(button, false);
-  }
-});
-
-// ==================== SUMMARIZE LINK MODE (Full Pipeline) ====================
-
-const summarizeLinkForm = document.getElementById('summarize-link-form');
-if (summarizeLinkForm) {
-  const linkProgress = document.getElementById('summarize-link-progress');
-  const linkProgressFill = document.getElementById('summarize-link-progress-fill');
-  const linkProgressTitle = document.getElementById('summarize-link-progress-title');
-  const linkProgressPercent = document.getElementById('summarize-link-progress-percent');
-  const linkProgressPhase = document.getElementById('summarize-link-progress-phase');
-  const linkProgressSpeed = document.getElementById('summarize-link-progress-speed');
-  const linkProgressCurrent = document.getElementById('summarize-link-progress-current');
-  const linkProgressEta = document.getElementById('summarize-link-progress-eta');
-
-  function resetLinkProgress() {
-    if (linkProgressFill) linkProgressFill.style.width = '0%';
-    if (linkProgressPercent) linkProgressPercent.textContent = '0%';
-    if (linkProgressTitle) linkProgressTitle.textContent = 'Processing...';
-    if (linkProgressPhase) linkProgressPhase.textContent = '';
-    if (linkProgressSpeed) linkProgressSpeed.textContent = '';
-    if (linkProgressCurrent) linkProgressCurrent.textContent = '';
-    if (linkProgressEta) linkProgressEta.textContent = '';
-  }
-
-  summarizeLinkForm.addEventListener('submit', async (e) => {
-    e.preventDefault();
-    const button = document.getElementById('summarize-link-btn');
-    const url = document.getElementById('summarize-url').value;
-    const style = document.getElementById('summarize-link-style').value;
-    const language = document.getElementById('summarize-link-language').value;
-    const resultDiv = document.getElementById('summarize-link-result');
-
-    setLoading(button, true);
-    resetLinkProgress();
-    linkProgress.style.display = 'block';
-    resultDiv.classList.remove('show');
-
-    const params = new URLSearchParams({ url, style, language });
-    const eventSource = new EventSource(`${API_URL}/summarize-stream?${params}`);
-
-    eventSource.addEventListener('status', (e) => {
-      const data = JSON.parse(e.data);
-      linkProgressTitle.textContent = data.message;
-      if (data.percent !== undefined) {
-        linkProgressFill.style.width = `${data.percent}%`;
-        linkProgressPercent.textContent = `${Math.round(data.percent)}%`;
-      }
-    });
-
-    eventSource.addEventListener('info', (e) => {
-      const data = JSON.parse(e.data);
-      linkProgressTitle.textContent = data.totalVideos > 1
-        ? `Processing playlist: ${data.playlistTitle} (${data.totalVideos} videos)`
-        : `Processing: ${data.title}`;
-    });
-
-    eventSource.addEventListener('progress', (e) => {
-      const data = JSON.parse(e.data);
-      linkProgressFill.style.width = `${data.percent}%`;
-      linkProgressPercent.textContent = `${Math.round(data.percent)}%`;
-      linkProgressPhase.textContent = data.phaseLabel || '';
-      if (data.speed) linkProgressSpeed.textContent = data.speed;
-      if (data.title) {
-        linkProgressCurrent.innerHTML = `${data.phaseLabel}: <span class="video-title">${data.title}</span>`;
-      }
-      if (data.totalVideos > 1) {
-        linkProgressCurrent.innerHTML += ` (${data.currentVideo}/${data.totalVideos})`;
-      }
-    });
-
-    eventSource.addEventListener('video-complete', (e) => {
-      const data = JSON.parse(e.data);
-      linkProgressCurrent.innerHTML = `Downloaded: <span class="video-title">${data.title}</span>`;
-    });
-
-    eventSource.addEventListener('transcribe-complete', (e) => {
-      const data = JSON.parse(e.data);
-      linkProgressCurrent.innerHTML = `Transcribed: <span class="video-title">${data.title}</span>`;
-    });
-
-    eventSource.addEventListener('summarize-complete', (e) => {
-      const data = JSON.parse(e.data);
-      linkProgressCurrent.innerHTML = `Summarized: <span class="video-title">${data.title}</span>`;
-    });
-
-    eventSource.addEventListener('complete', (e) => {
-      const data = JSON.parse(e.data);
-      eventSource.close();
-      linkProgressFill.style.width = '100%';
-      linkProgressPercent.textContent = '100%';
-      linkProgressTitle.textContent = 'Complete!';
-      linkProgressPhase.textContent = '';
-      linkProgressEta.textContent = `Total: ${formatTime(data.totalTime)}`;
-
-      showResult('summarize-link-result', true, `
-        <h3>Pipeline Complete!</h3>
-        ${data.playlistTitle ? `<p>Playlist: ${data.playlistTitle}</p>` : ''}
-        <p>Downloaded: ${data.downloadedCount}/${data.totalVideos} | Transcribed: ${data.transcribedCount} | Summarized: ${data.summarizedCount}</p>
-        <ul>${data.results.map(r => `
-          <li>
-            <span class="${r.success ? 'icon-success' : 'icon-error'}">${r.success ? '✓' : '✗'}</span>
-            <strong>${r.title}</strong>
-            ${r.summaryUrl ? `<a href="${r.summaryUrl}" target="_blank">Summary</a>` : ''}
-            ${r.transcriptionUrl ? `<a href="${r.transcriptionUrl}" target="_blank">Transcript</a>` : ''}
-            ${r.error ? `<small>(${r.error})</small>` : ''}
-          </li>
-        `).join('')}</ul>
-        ${data.results[0]?.summary ? `
-          <h4>Summary Preview:</h4>
-          <div class="summary-output">${data.results[0].summary.substring(0, 2000)}${data.results[0].summary.length > 2000 ? '...' : ''}</div>
-        ` : ''}
-      `);
-      setLoading(button, false);
-    });
-
-    eventSource.addEventListener('error', (e) => {
-      let errorMsg = 'Processing failed';
-      try { errorMsg = JSON.parse(e.data).message || errorMsg; } catch {}
-      eventSource.close();
-      linkProgress.style.display = 'none';
-      showResult('summarize-link-result', false, `<h3>Error</h3><p>${errorMsg}</p>`);
-      setLoading(button, false);
-    });
-
-    eventSource.onerror = () => {
-      eventSource.close();
-      linkProgress.style.display = 'none';
-      showResult('summarize-link-result', false, `<h3>Error</h3><p>Connection lost</p>`);
-      setLoading(button, false);
-    };
-  });
-}
+// API Base URL
+const API_URL = '';
+
+// Tab switching
+document.querySelectorAll('.tab').forEach(tab => {
+  tab.addEventListener('click', () => {
+    document.querySelectorAll('.tab').forEach(t => t.classList.remove('active'));
+    document.querySelectorAll('.tab-content').forEach(c => c.classList.remove('active'));
+    tab.classList.add('active');
+    document.getElementById(tab.dataset.tab).classList.add('active');
+  });
+});
+
+// Helper: Show result
+function showResult(elementId, success, content) {
+  const el = document.getElementById(elementId);
+  el.className = `result show ${success ? 'success' : 'error'}`;
+  el.innerHTML = content;
+}
+
+// Helper: Set loading state
+function setLoading(button, loading) {
+  button.disabled = loading;
+  button.classList.toggle('loading', loading);
+}
+
+// Format seconds to MM:SS or HH:MM:SS
+function formatTime(seconds) {
+  if (!seconds || seconds < 0) return '--:--';
+  const hrs = Math.floor(seconds / 3600);
+  const mins = Math.floor((seconds % 3600) / 60);
+  const secs = Math.floor(seconds % 60);
+  if (hrs > 0) {
+    return `${hrs}:${String(mins).padStart(2, '0')}:${String(secs).padStart(2, '0')}`;
+  }
+  return `${mins}:${String(secs).padStart(2, '0')}`;
+}
+
+// Format file size
+function formatSize(bytes) {
+  if (!bytes) return '';
+  const units = ['B', 'KB', 'MB', 'GB'];
+  let i = 0;
+  while (bytes >= 1024 && i < units.length - 1) {
+    bytes /= 1024;
+    i++;
+  }
+  return `${bytes.toFixed(1)} ${units[i]}`;
+}
+
+// ==================== DOWNLOAD TAB ====================
+
+const progressContainer = document.getElementById('download-progress');
+const progressFill = document.getElementById('progress-fill');
+const progressPercent = document.getElementById('progress-percent');
+const progressTitle = document.getElementById('progress-title');
+const progressEta = document.getElementById('progress-eta');
+const progressInfo = document.getElementById('progress-info');
+const progressSpeed = document.getElementById('progress-speed');
+const progressCurrent = document.getElementById('progress-current');
+
+function updateDownloadProgress(data) {
+  progressFill.style.width = `${data.percent}%`;
+  progressPercent.textContent = `${data.percent}%`;
+
+  if (data.totalVideos > 1) {
+    progressInfo.textContent = `Video ${data.currentVideo}/${data.totalVideos}`;
+  } else {
+    progressInfo.textContent = '';
+  }
+
+  if (data.speed) progressSpeed.textContent = data.speed;
+  if (data.estimatedRemaining) {
+    progressEta.textContent = `ETA: ${formatTime(data.estimatedRemaining)}`;
+  } else if (data.eta) {
+    progressEta.textContent = `ETA: ${data.eta}`;
+  }
+  if (data.title) {
+    progressCurrent.innerHTML = `Downloading: <span class="video-title">${data.title}</span>`;
+  }
+}
+
+function resetDownloadProgress() {
+  progressFill.style.width = '0%';
+  progressPercent.textContent = '0%';
+  progressTitle.textContent = 'Downloading...';
+  progressEta.textContent = '';
+  progressInfo.textContent = '';
+  progressSpeed.textContent = '';
+  progressCurrent.textContent = '';
+}
+
+document.getElementById('download-form').addEventListener('submit', async (e) => {
+  e.preventDefault();
+  const button = e.target.querySelector('button[type="submit"]');
+  const url = document.getElementById('download-url').value;
+  const resultDiv = document.getElementById('download-result');
+
+  setLoading(button, true);
+  resetDownloadProgress();
+  progressContainer.style.display = 'block';
+  resultDiv.classList.remove('show');
+
+  const eventSource = new EventSource(`${API_URL}/download-stream?url=${encodeURIComponent(url)}`);
+
+  eventSource.addEventListener('status', (e) => {
+    progressTitle.textContent = JSON.parse(e.data).message;
+  });
+
+  eventSource.addEventListener('info', (e) => {
+    const data = JSON.parse(e.data);
+    progressTitle.textContent = data.totalVideos > 1
+      ? `Downloading playlist: ${data.playlistTitle} (${data.totalVideos} videos)`
+      : `Downloading: ${data.title}`;
+  });
+
+  eventSource.addEventListener('progress', (e) => updateDownloadProgress(JSON.parse(e.data)));
+
+  eventSource.addEventListener('video-complete', (e) => {
+    const data = JSON.parse(e.data);
+    progressCurrent.innerHTML = `Completed: <span class="video-title">${data.title}</span> (${data.videosCompleted}/${data.totalVideos})`;
+  });
+
+  eventSource.addEventListener('complete', (e) => {
+    const data = JSON.parse(e.data);
+    eventSource.close();
+    progressFill.style.width = '100%';
+    progressPercent.textContent = '100%';
+    progressTitle.textContent = 'Download Complete!';
+    progressEta.textContent = `Total: ${formatTime(data.totalTime)}`;
+
+    showResult('download-result', true, `
+      <h3>Download Complete!</h3>
+      <p>${data.successCount}/${data.totalVideos} videos downloaded</p>
+      ${data.playlistTitle ? `<p>Playlist: ${data.playlistTitle}</p>` : ''}
+      <ul>${data.videos.map(v => `
+        <li>
+          <span class="${v.success ? 'icon-success' : 'icon-error'}">${v.success ? '✓' : '✗'}</span>
+          ${v.title}
+          ${v.success && v.fileUrl ? `<a href="${v.fileUrl}" target="_blank">Download</a>` : ''}
+          ${v.error ? `<small>(${v.error})</small>` : ''}
+        </li>
+      `).join('')}</ul>
+    `);
+    setLoading(button, false);
+  });
+
+  eventSource.addEventListener('error', (e) => {
+    let errorMsg = 'Download failed';
+    try { errorMsg = JSON.parse(e.data).message || errorMsg; } catch {}
+    eventSource.close();
+    progressContainer.style.display = 'none';
+    showResult('download-result', false, `<h3>Error</h3><p>${errorMsg}</p>`);
+    setLoading(button, false);
+  });
+
+  eventSource.onerror = () => {
+    eventSource.close();
+    progressContainer.style.display = 'none';
+    showResult('download-result', false, `<h3>Error</h3><p>Connection lost</p>`);
+    setLoading(button, false);
+  };
+});
+
+// ==================== CONVERT TAB (Video to MP3) ====================
+
+let convertSelectedFiles = [];
+const convertDropZone = document.getElementById('convert-drop-zone');
+const convertFileInput = document.getElementById('convert-file-input');
+const convertSelectedFilesDiv = document.getElementById('convert-selected-files');
+const convertFilesList = document.getElementById('convert-files-list');
+const convertBtn = document.getElementById('convert-btn');
+const convertClearFilesBtn = document.getElementById('convert-clear-files');
+
+function updateConvertFilesList() {
+  if (convertSelectedFiles.length === 0) {
+    convertSelectedFilesDiv.style.display = 'none';
+    convertBtn.disabled = true;
+    return;
+  }
+
+  convertSelectedFilesDiv.style.display = 'block';
+  convertBtn.disabled = false;
+
+  convertFilesList.innerHTML = convertSelectedFiles.map((file, index) => `
+    <li>
+      <span class="file-name">${file.name}</span>
+      <span class="file-size">${formatSize(file.size)}</span>
+      <button type="button" class="remove-file" data-index="${index}">×</button>
+    </li>
+  `).join('');
+
+  // Add remove handlers
+  convertFilesList.querySelectorAll('.remove-file').forEach(btn => {
+    btn.addEventListener('click', () => {
+      convertSelectedFiles.splice(parseInt(btn.dataset.index), 1);
+      updateConvertFilesList();
+    });
+  });
+}
+
+function addConvertFiles(files) {
+  const videoAudioFiles = Array.from(files).filter(f =>
+    f.type.startsWith('video/') || f.type.startsWith('audio/') ||
+    f.name.match(/\.(mp4|avi|mkv|mov|m4a|wav|flac|ogg|webm|wmv|flv)$/i)
+  );
+  convertSelectedFiles = [...convertSelectedFiles, ...videoAudioFiles];
+  updateConvertFilesList();
+}
+
+// Drag & Drop events for convert
+convertDropZone.addEventListener('click', () => convertFileInput.click());
+
+convertDropZone.addEventListener('dragover', (e) => {
+  e.preventDefault();
+  convertDropZone.classList.add('drag-over');
+});
+
+convertDropZone.addEventListener('dragleave', () => {
+  convertDropZone.classList.remove('drag-over');
+});
+
+convertDropZone.addEventListener('drop', (e) => {
+  e.preventDefault();
+  convertDropZone.classList.remove('drag-over');
+  addConvertFiles(e.dataTransfer.files);
+});
+
+convertFileInput.addEventListener('change', () => {
+  addConvertFiles(convertFileInput.files);
+  convertFileInput.value = '';
+});
+
+convertClearFilesBtn.addEventListener('click', () => {
+  convertSelectedFiles = [];
+  updateConvertFilesList();
+});
+
+// Convert form submit
+document.getElementById('convert-form').addEventListener('submit', async (e) => {
+  e.preventDefault();
+  if (convertSelectedFiles.length === 0) return;
+
+  const button = convertBtn;
+  const bitrate = document.getElementById('convert-bitrate').value;
+  const quality = document.getElementById('convert-quality').value;
+
+  const convertProgress = document.getElementById('convert-progress');
+  const convertProgressFill = document.getElementById('convert-progress-fill');
+  const convertProgressTitle = document.getElementById('convert-progress-title');
+  const convertProgressPercent = document.getElementById('convert-progress-percent');
+  const convertProgressInfo = document.getElementById('convert-progress-info');
+  const convertProgressCurrent = document.getElementById('convert-progress-current');
+
+  setLoading(button, true);
+  convertProgress.style.display = 'block';
+  convertProgressFill.style.width = '0%';
+  convertProgressTitle.textContent = 'Converting to MP3...';
+  convertProgressPercent.textContent = '0%';
+  convertProgressInfo.textContent = `0/${convertSelectedFiles.length} files`;
+  document.getElementById('convert-result').classList.remove('show');
+
+  const formData = new FormData();
+  convertSelectedFiles.forEach(file => formData.append('files', file));
+  formData.append('bitrate', bitrate);
+  formData.append('quality', quality);
+
+  try {
+    const response = await fetch(`${API_URL}/convert-to-mp3`, {
+      method: 'POST',
+      body: formData
+    });
+
+    const data = await response.json();
+
+    if (!response.ok) throw new Error(data.error || 'Conversion failed');
+
+    convertProgressFill.style.width = '100%';
+    convertProgressPercent.textContent = '100%';
+    convertProgressTitle.textContent = 'Conversion Complete!';
+    convertProgressInfo.textContent = `${data.successCount}/${data.totalFiles} files`;
+
+    showResult('convert-result', true, `
+      <h3>Conversion Complete!</h3>
+      <p>${data.successCount}/${data.totalFiles} files converted to MP3</p>
+      <div class="file-results">
+        ${data.results.map(r => r.success ? `
+          <div class="file-result success">
+            <div class="file-info">
+              <strong>${r.fileName}</strong>
+              <span class="file-size">${r.size}</span>
+            </div>
+            <a href="${r.outputUrl}" download class="btn btn-small btn-primary">Download MP3</a>
+          </div>
+        ` : `
+          <div class="file-result error">
+            <strong>${r.fileName}</strong>
+            <span class="error-msg">${r.error}</span>
+          </div>
+        `).join('')}
+      </div>
+    `);
+
+    // Clear selected files after successful conversion
+    convertSelectedFiles = [];
+    updateConvertFilesList();
+
+  } catch (error) {
+    showResult('convert-result', false, `<h3>Error</h3><p>${error.message}</p>`);
+  } finally {
+    setLoading(button, false);
+    setTimeout(() => {
+      convertProgress.style.display = 'none';
+    }, 1000);
+  }
+});
+
+// ==================== TRANSCRIBE TAB (Drag & Drop) ====================
+
+let selectedFiles = [];
+const dropZone = document.getElementById('drop-zone');
+const fileInput = document.getElementById('file-input');
+const selectedFilesDiv = document.getElementById('selected-files');
+const filesList = document.getElementById('files-list');
+const transcribeBtn = document.getElementById('transcribe-btn');
+const clearFilesBtn = document.getElementById('clear-files');
+
+function updateFilesList() {
+  if (selectedFiles.length === 0) {
+    selectedFilesDiv.style.display = 'none';
+    transcribeBtn.disabled = true;
+    return;
+  }
+
+  selectedFilesDiv.style.display = 'block';
+  transcribeBtn.disabled = false;
+
+  filesList.innerHTML = selectedFiles.map((file, index) => `
+    <li>
+      <span class="file-name">${file.name}</span>
+      <span class="file-size">${formatSize(file.size)}</span>
+      <button type="button" class="remove-file" data-index="${index}">×</button>
+    </li>
+  `).join('');
+
+  // Add remove handlers
+  filesList.querySelectorAll('.remove-file').forEach(btn => {
+    btn.addEventListener('click', () => {
+      selectedFiles.splice(parseInt(btn.dataset.index), 1);
+      updateFilesList();
+    });
+  });
+}
+
+function addFiles(files) {
+  const audioFiles = Array.from(files).filter(f =>
+    f.type.startsWith('audio/') || f.name.match(/\.(mp3|wav|m4a|ogg|flac)$/i)
+  );
+  selectedFiles = [...selectedFiles, ...audioFiles];
+  updateFilesList();
+}
+
+// Drag & Drop events
+dropZone.addEventListener('click', () => fileInput.click());
+
+dropZone.addEventListener('dragover', (e) => {
+  e.preventDefault();
+  dropZone.classList.add('drag-over');
+});
+
+dropZone.addEventListener('dragleave', () => {
+  dropZone.classList.remove('drag-over');
+});
+
+dropZone.addEventListener('drop', (e) => {
+  e.preventDefault();
+  dropZone.classList.remove('drag-over');
+  addFiles(e.dataTransfer.files);
+});
+
+fileInput.addEventListener('change', () => {
+  addFiles(fileInput.files);
+  fileInput.value = '';
+});
+
+clearFilesBtn.addEventListener('click', () => {
+  selectedFiles = [];
+  updateFilesList();
+});
+
+// Transcribe form submit
+document.getElementById('transcribe-form').addEventListener('submit', async (e) => {
+  e.preventDefault();
+  if (selectedFiles.length === 0) return;
+
+  const button = transcribeBtn;
+  const language = document.getElementById('transcribe-lang').value;
+  const model = document.getElementById('transcribe-model').value;
+
+  const transcribeProgress = document.getElementById('transcribe-progress');
+  const transcribeProgressFill = document.getElementById('transcribe-progress-fill');
+  const transcribeProgressTitle = document.getElementById('transcribe-progress-title');
+  const transcribeProgressPercent = document.getElementById('transcribe-progress-percent');
+  const transcribeProgressInfo = document.getElementById('transcribe-progress-info');
+  const transcribeProgressCurrent = document.getElementById('transcribe-progress-current');
+
+  setLoading(button, true);
+  transcribeProgress.style.display = 'block';
+  transcribeProgressFill.style.width = '0%';
+  transcribeProgressTitle.textContent = 'Uploading and transcribing...';
+  transcribeProgressPercent.textContent = '0%';
+  transcribeProgressInfo.textContent = `0/${selectedFiles.length} files`;
+  document.getElementById('transcribe-result').classList.remove('show');
+
+  const formData = new FormData();
+  selectedFiles.forEach(file => formData.append('files', file));
+  if (language) formData.append('language', language);
+  formData.append('model', model);
+
+  try {
+    const response = await fetch(`${API_URL}/upload-transcribe`, {
+      method: 'POST',
+      body: formData
+    });
+
+    const data = await response.json();
+
+    if (!response.ok) throw new Error(data.error || 'Transcription failed');
+
+    transcribeProgressFill.style.width = '100%';
+    transcribeProgressPercent.textContent = '100%';
+    transcribeProgressTitle.textContent = 'Transcription Complete!';
+    transcribeProgressInfo.textContent = `${data.successCount}/${data.totalFiles} files`;
+
+    showResult('transcribe-result', true, `
+      <h3>Transcription Complete!</h3>
+      <p>${data.successCount}/${data.totalFiles} files transcribed</p>
+      <ul>${data.results.map(r => `
+        <li>
+          <span class="${r.success ? 'icon-success' : 'icon-error'}">${r.success ? '✓' : '✗'}</span>
+          ${r.fileName}
+          ${r.success && r.transcriptionUrl ? `<a href="${r.transcriptionUrl}" target="_blank">View</a>` : ''}
+          ${r.error ? `<small>(${r.error})</small>` : ''}
+        </li>
+      `).join('')}</ul>
+      ${data.results[0]?.text ? `
+        <h4>Preview (first file):</h4>
+        <div class="preview">${data.results[0].text.substring(0, 1000)}${data.results[0].text.length > 1000 ? '...' : ''}</div>
+      ` : ''}
+    `);
+
+    selectedFiles = [];
+    updateFilesList();
+
+  } catch (error) {
+    transcribeProgress.style.display = 'none';
+    showResult('transcribe-result', false, `<h3>Error</h3><p>${error.message}</p>`);
+  } finally {
+    setLoading(button, false);
+  }
+});
+
+// ==================== PROCESS TAB (Download + Transcribe) ====================
+
+const processProgress = document.getElementById('process-progress');
+const processProgressFill = document.getElementById('process-progress-fill');
+const processProgressTitle = document.getElementById('process-progress-title');
+const processProgressPercent = document.getElementById('process-progress-percent');
+const processProgressPhase = document.getElementById('process-progress-phase');
+const processProgressSpeed = document.getElementById('process-progress-speed');
+const processProgressCurrent = document.getElementById('process-progress-current');
+const processProgressEta = document.getElementById('process-progress-eta');
+
+function resetProcessProgress() {
+  processProgressFill.style.width = '0%';
+  processProgressPercent.textContent = '0%';
+  processProgressTitle.textContent = 'Processing...';
+  processProgressPhase.textContent = '';
+  processProgressSpeed.textContent = '';
+  processProgressCurrent.textContent = '';
+  processProgressEta.textContent = '';
+}
+
+document.getElementById('process-form').addEventListener('submit', async (e) => {
+  e.preventDefault();
+  const button = e.target.querySelector('button[type="submit"]');
+  const url = document.getElementById('process-url').value;
+  const language = document.getElementById('process-lang').value;
+  const model = document.getElementById('process-model').value;
+  const resultDiv = document.getElementById('process-result');
+
+  setLoading(button, true);
+  resetProcessProgress();
+  processProgress.style.display = 'block';
+  resultDiv.classList.remove('show');
+
+  const params = new URLSearchParams({ url });
+  if (language) params.append('language', language);
+  params.append('model', model);
+
+  const eventSource = new EventSource(`${API_URL}/process-stream?${params}`);
+
+  eventSource.addEventListener('status', (e) => {
+    const data = JSON.parse(e.data);
+    processProgressTitle.textContent = data.message;
+    if (data.phase === 'transcribing') {
+      processProgressPhase.textContent = 'Transcribing';
+    }
+  });
+
+  eventSource.addEventListener('info', (e) => {
+    const data = JSON.parse(e.data);
+    processProgressTitle.textContent = data.totalVideos > 1
+      ? `Processing playlist: ${data.playlistTitle} (${data.totalVideos} videos)`
+      : `Processing: ${data.title}`;
+  });
+
+  eventSource.addEventListener('progress', (e) => {
+    const data = JSON.parse(e.data);
+    processProgressFill.style.width = `${data.percent}%`;
+    processProgressPercent.textContent = `${Math.round(data.percent)}%`;
+    processProgressPhase.textContent = data.phaseLabel || '';
+    if (data.speed) processProgressSpeed.textContent = data.speed;
+    if (data.title) {
+      processProgressCurrent.innerHTML = `${data.phaseLabel}: <span class="video-title">${data.title}</span>`;
+    }
+    if (data.totalVideos > 1) {
+      processProgressCurrent.innerHTML += ` (${data.currentVideo}/${data.totalVideos})`;
+    }
+  });
+
+  eventSource.addEventListener('video-complete', (e) => {
+    const data = JSON.parse(e.data);
+    processProgressCurrent.innerHTML = `Downloaded: <span class="video-title">${data.title}</span>`;
+  });
+
+  eventSource.addEventListener('transcribe-complete', (e) => {
+    const data = JSON.parse(e.data);
+    processProgressCurrent.innerHTML = `Transcribed: <span class="video-title">${data.title}</span> (${data.videosCompleted}/${data.totalFiles})`;
+  });
+
+  eventSource.addEventListener('complete', (e) => {
+    const data = JSON.parse(e.data);
+    eventSource.close();
+    processProgressFill.style.width = '100%';
+    processProgressPercent.textContent = '100%';
+    processProgressTitle.textContent = 'Processing Complete!';
+    processProgressPhase.textContent = '';
+    processProgressEta.textContent = `Total: ${formatTime(data.totalTime)}`;
+
+    showResult('process-result', true, `
+      <h3>Processing Complete!</h3>
+      ${data.playlistTitle ? `<p>Playlist: ${data.playlistTitle}</p>` : ''}
+      <p>Downloaded: ${data.downloadedCount}/${data.totalVideos}</p>
+      <p>Transcribed: ${data.transcribedCount}/${data.totalVideos}</p>
+      <ul>${data.results.map(r => `
+        <li>
+          <span class="${r.transcriptionSuccess ? 'icon-success' : 'icon-error'}">${r.transcriptionSuccess ? '✓' : '✗'}</span>
+          ${r.title}
+          ${r.audioUrl ? `<a href="${r.audioUrl}" target="_blank">MP3</a>` : ''}
+          ${r.transcriptionUrl ? `<a href="${r.transcriptionUrl}" target="_blank">TXT</a>` : ''}
+          ${r.error ? `<small>(${r.error})</small>` : ''}
+        </li>
+      `).join('')}</ul>
+      ${data.results[0]?.text ? `
+        <h4>Preview (first file):</h4>
+        <div class="preview">${data.results[0].text.substring(0, 1000)}${data.results[0].text.length > 1000 ? '...' : ''}</div>
+      ` : ''}
+    `);
+    setLoading(button, false);
+  });
+
+  eventSource.addEventListener('error', (e) => {
+    let errorMsg = 'Processing failed';
+    try { errorMsg = JSON.parse(e.data).message || errorMsg; } catch {}
+    eventSource.close();
+    processProgress.style.display = 'none';
+    showResult('process-result', false, `<h3>Error</h3><p>${errorMsg}</p>`);
+    setLoading(button, false);
+  });
+
+  eventSource.onerror = () => {
+    eventSource.close();
+    processProgress.style.display = 'none';
+    showResult('process-result', false, `<h3>Error</h3><p>Connection lost</p>`);
+    setLoading(button, false);
+  };
+});
+
+// ==================== TRANSLATE CHECKBOXES (Transcribe & Process tabs) ====================
+
+// Transcribe tab checkbox
+const transcribeTranslateCheckbox = document.getElementById('transcribe-translate');
+const transcribeTranslateLang = document.getElementById('transcribe-translate-lang');
+
+transcribeTranslateCheckbox.addEventListener('change', () => {
+  transcribeTranslateLang.disabled = !transcribeTranslateCheckbox.checked;
+});
+
+// Process tab checkbox
+const processTranslateCheckbox = document.getElementById('process-translate');
+const processTranslateLang = document.getElementById('process-translate-lang');
+
+processTranslateCheckbox.addEventListener('change', () => {
+  processTranslateLang.disabled = !processTranslateCheckbox.checked;
+});
+
+// ==================== TRANSLATE TAB ====================
+
+// Mode switching
+const translateModeBtns = document.querySelectorAll('.mode-btn');
+const translateTextMode = document.getElementById('translate-text-mode');
+const translateFileMode = document.getElementById('translate-file-mode');
+
+translateModeBtns.forEach(btn => {
+  btn.addEventListener('click', () => {
+    translateModeBtns.forEach(b => b.classList.remove('active'));
+    btn.classList.add('active');
+
+    if (btn.dataset.mode === 'text') {
+      translateTextMode.style.display = 'block';
+      translateFileMode.style.display = 'none';
+    } else {
+      translateTextMode.style.display = 'none';
+      translateFileMode.style.display = 'block';
+    }
+  });
+});
+
+// Text translation form
+document.getElementById('translate-text-form').addEventListener('submit', async (e) => {
+  e.preventDefault();
+  const button = document.getElementById('translate-text-btn');
+  const text = document.getElementById('translate-input').value;
+  const sourceLang = document.getElementById('translate-source').value;
+  const targetLang = document.getElementById('translate-target').value;
+
+  if (!text.trim()) {
+    showResult('translate-text-result', false, '<h3>Error</h3><p>Please enter text to translate</p>');
+    return;
+  }
+
+  setLoading(button, true);
+  document.getElementById('translate-text-result').classList.remove('show');
+
+  try {
+    const response = await fetch(`${API_URL}/translate`, {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ text, targetLang, sourceLang: sourceLang || null })
+    });
+
+    const data = await response.json();
+    if (!response.ok) throw new Error(data.error || 'Translation failed');
+
+    showResult('translate-text-result', true, `
+      <h3>Translation Complete!</h3>
+      <p><strong>From:</strong> ${data.sourceLanguage} <strong>To:</strong> ${data.targetLanguage}</p>
+      <div class="translation-output">${data.translatedText}</div>
+    `);
+  } catch (error) {
+    showResult('translate-text-result', false, `<h3>Error</h3><p>${error.message}</p>`);
+  } finally {
+    setLoading(button, false);
+  }
+});
+
+// File translation - Drag & Drop
+let translateSelectedFiles = [];
+const translateDropZone = document.getElementById('translate-drop-zone');
+const translateFileInput = document.getElementById('translate-file-input');
+const translateSelectedFilesDiv = document.getElementById('translate-selected-files');
+const translateFilesList = document.getElementById('translate-files-list');
+const translateFileBtn = document.getElementById('translate-file-btn');
+const translateClearFilesBtn = document.getElementById('translate-clear-files');
+
+function updateTranslateFilesList() {
+  if (translateSelectedFiles.length === 0) {
+    translateSelectedFilesDiv.style.display = 'none';
+    translateFileBtn.disabled = true;
+    return;
+  }
+
+  translateSelectedFilesDiv.style.display = 'block';
+  translateFileBtn.disabled = false;
+
+  translateFilesList.innerHTML = translateSelectedFiles.map((file, index) => `
+    <li>
+      <span class="file-name">${file.name}</span>
+      <span class="file-size">${formatSize(file.size)}</span>
+      <button type="button" class="remove-file" data-index="${index}">x</button>
+    </li>
+  `).join('');
+
+  translateFilesList.querySelectorAll('.remove-file').forEach(btn => {
+    btn.addEventListener('click', () => {
+      translateSelectedFiles.splice(parseInt(btn.dataset.index), 1);
+      updateTranslateFilesList();
+    });
+  });
+}
+
+function addTranslateFiles(files) {
+  const textFiles = Array.from(files).filter(f =>
+    f.type === 'text/plain' || f.name.endsWith('.txt')
+  );
+  translateSelectedFiles = [...translateSelectedFiles, ...textFiles];
+  updateTranslateFilesList();
+}
+
+translateDropZone.addEventListener('click', () => translateFileInput.click());
+
+translateDropZone.addEventListener('dragover', (e) => {
+  e.preventDefault();
+  translateDropZone.classList.add('drag-over');
+});
+
+translateDropZone.addEventListener('dragleave', () => {
+  translateDropZone.classList.remove('drag-over');
+});
+
+translateDropZone.addEventListener('drop', (e) => {
+  e.preventDefault();
+  translateDropZone.classList.remove('drag-over');
+  addTranslateFiles(e.dataTransfer.files);
+});
+
+translateFileInput.addEventListener('change', () => {
+  addTranslateFiles(translateFileInput.files);
+  translateFileInput.value = '';
+});
+
+translateClearFilesBtn.addEventListener('click', () => {
+  translateSelectedFiles = [];
+  updateTranslateFilesList();
+});
+
+// File translation form submit
+document.getElementById('translate-file-form').addEventListener('submit', async (e) => {
+  e.preventDefault();
+  if (translateSelectedFiles.length === 0) return;
+
+  const button = translateFileBtn;
+  const sourceLang = document.getElementById('translate-file-source').value;
+  const targetLang = document.getElementById('translate-file-target').value;
+
+  setLoading(button, true);
+  document.getElementById('translate-file-result').classList.remove('show');
+
+  const formData = new FormData();
+  translateSelectedFiles.forEach(file => formData.append('files', file));
+  formData.append('targetLang', targetLang);
+  if (sourceLang) formData.append('sourceLang', sourceLang);
+
+  try {
+    const response = await fetch(`${API_URL}/translate-file`, {
+      method: 'POST',
+      body: formData
+    });
+
+    const data = await response.json();
+    if (!response.ok) throw new Error(data.error || 'Translation failed');
+
+    showResult('translate-file-result', true, `
+      <h3>Translation Complete!</h3>
+      <p>${data.successCount}/${data.totalFiles} files translated</p>
+      <ul>${data.results.map(r => `
+        <li>
+          <span class="${r.success ? 'icon-success' : 'icon-error'}">${r.success ? '✓' : '✗'}</span>
+          ${r.fileName || r.originalPath}
+          ${r.success && r.translationUrl ? `<a href="${r.translationUrl}" target="_blank">View</a>` : ''}
+          ${r.error ? `<small>(${r.error})</small>` : ''}
+        </li>
+      `).join('')}</ul>
+      ${data.results[0]?.translatedText ? `
+        <h4>Preview (first file):</h4>
+        <div class="translation-output">${data.results[0].translatedText.substring(0, 1000)}${data.results[0].translatedText.length > 1000 ? '...' : ''}</div>
+      ` : ''}
+    `);
+
+    translateSelectedFiles = [];
+    updateTranslateFilesList();
+
+  } catch (error) {
+    showResult('translate-file-result', false, `<h3>Error</h3><p>${error.message}</p>`);
+  } finally {
+    setLoading(button, false);
+  }
+});
+
+// ==================== SUMMARIZE TAB ====================
+
+// Mode switching
+const summarizeModeBtns = document.querySelectorAll('.summarize-mode-selector .mode-btn');
+const summarizeTextMode = document.getElementById('summarize-text-mode');
+const summarizeFileMode = document.getElementById('summarize-file-mode');
+
+const summarizeLinkMode = document.getElementById('summarize-link-mode');
+
+summarizeModeBtns.forEach(btn => {
+  btn.addEventListener('click', () => {
+    summarizeModeBtns.forEach(b => b.classList.remove('active'));
+    btn.classList.add('active');
+
+    summarizeTextMode.style.display = 'none';
+    summarizeFileMode.style.display = 'none';
+    if (summarizeLinkMode) summarizeLinkMode.style.display = 'none';
+
+    if (btn.dataset.mode === 'text') {
+      summarizeTextMode.style.display = 'block';
+    } else if (btn.dataset.mode === 'file') {
+      summarizeFileMode.style.display = 'block';
+    } else if (btn.dataset.mode === 'link' && summarizeLinkMode) {
+      summarizeLinkMode.style.display = 'block';
+    }
+  });
+});
+
+// Text summarization form
+document.getElementById('summarize-text-form').addEventListener('submit', async (e) => {
+  e.preventDefault();
+  const button = document.getElementById('summarize-text-btn');
+  const text = document.getElementById('summarize-input').value;
+  const style = document.getElementById('summarize-style').value;
+  const language = document.getElementById('summarize-language').value;
+
+  if (!text.trim()) {
+    showResult('summarize-text-result', false, '<h3>Error</h3><p>Please enter text to summarize</p>');
+    return;
+  }
+
+  setLoading(button, true);
+  document.getElementById('summarize-text-result').classList.remove('show');
+
+  try {
+    const response = await fetch(`${API_URL}/summarize`, {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json' },
+      body: JSON.stringify({ text, style, language })
+    });
+
+    const data = await response.json();
+    if (!response.ok) throw new Error(data.error || 'Summarization failed');
+
+    showResult('summarize-text-result', true, `
+      <h3>Summary Complete!</h3>
+      <p><strong>Model:</strong> ${data.model} | <strong>Style:</strong> ${data.style} | <strong>Chunks:</strong> ${data.chunks}</p>
+      <div class="summary-output">${data.summary}</div>
+    `);
+  } catch (error) {
+    showResult('summarize-text-result', false, `<h3>Error</h3><p>${error.message}</p>`);
+  } finally {
+    setLoading(button, false);
+  }
+});
+
+// File summarization - Drag & Drop
+let summarizeSelectedFiles = [];
+const summarizeDropZone = document.getElementById('summarize-drop-zone');
+const summarizeFileInput = document.getElementById('summarize-file-input');
+const summarizeSelectedFilesDiv = document.getElementById('summarize-selected-files');
+const summarizeFilesList = document.getElementById('summarize-files-list');
+const summarizeFileBtn = document.getElementById('summarize-file-btn');
+const summarizeClearFilesBtn = document.getElementById('summarize-clear-files');
+
+function updateSummarizeFilesList() {
+  if (!summarizeSelectedFilesDiv || !summarizeFileBtn || !summarizeFilesList) return;
+
+  if (summarizeSelectedFiles.length === 0) {
+    summarizeSelectedFilesDiv.style.display = 'none';
+    summarizeFileBtn.disabled = true;
+    return;
+  }
+
+  summarizeSelectedFilesDiv.style.display = 'block';
+  summarizeFileBtn.disabled = false;
+
+  summarizeFilesList.innerHTML = summarizeSelectedFiles.map((file, index) => `
+    <li>
+      <span class="file-name">${file.name}</span>
+      <span class="file-size">${formatSize(file.size)}</span>
+      <button type="button" class="remove-file" data-index="${index}">x</button>
+    </li>
+  `).join('');
+
+  summarizeFilesList.querySelectorAll('.remove-file').forEach(btn => {
+    btn.addEventListener('click', () => {
+      summarizeSelectedFiles.splice(parseInt(btn.dataset.index), 1);
+      updateSummarizeFilesList();
+    });
+  });
+}
+
+function addSummarizeFiles(files) {
+  console.log('Adding files:', files);
+  const textFiles = Array.from(files).filter(f =>
+    f.type === 'text/plain' || f.name.endsWith('.txt')
+  );
+  console.log('Filtered text files:', textFiles);
+  summarizeSelectedFiles = [...summarizeSelectedFiles, ...textFiles];
+  updateSummarizeFilesList();
+}
+
+if (summarizeDropZone) {
+  summarizeDropZone.addEventListener('click', () => {
+    console.log('Drop zone clicked');
+    summarizeFileInput.click();
+  });
+
+  summarizeDropZone.addEventListener('dragover', (e) => {
+    e.preventDefault();
+    e.stopPropagation();
+    summarizeDropZone.classList.add('drag-over');
+  });
+
+  summarizeDropZone.addEventListener('dragleave', (e) => {
+    e.preventDefault();
+    e.stopPropagation();
+    summarizeDropZone.classList.remove('drag-over');
+  });
+
+  summarizeDropZone.addEventListener('drop', (e) => {
+    e.preventDefault();
+    e.stopPropagation();
+    console.log('Files dropped:', e.dataTransfer.files);
+    summarizeDropZone.classList.remove('drag-over');
+    addSummarizeFiles(e.dataTransfer.files);
+  });
+}
+
+if (summarizeFileInput) {
+  summarizeFileInput.addEventListener('change', () => {
+    console.log('File input changed:', summarizeFileInput.files);
+    addSummarizeFiles(summarizeFileInput.files);
+    summarizeFileInput.value = '';
+  });
+}
+
+if (summarizeClearFilesBtn) {
+  summarizeClearFilesBtn.addEventListener('click', () => {
+    summarizeSelectedFiles = [];
+    updateSummarizeFilesList();
+  });
+}
+
+// File summarization form submit
+document.getElementById('summarize-file-form').addEventListener('submit', async (e) => {
+  e.preventDefault();
+  if (summarizeSelectedFiles.length === 0) return;
+
+  const button = summarizeFileBtn;
+  const style = document.getElementById('summarize-file-style').value;
+  const language = document.getElementById('summarize-file-language').value;
+
+  setLoading(button, true);
+  document.getElementById('summarize-file-result').classList.remove('show');
+
+  const formData = new FormData();
+  summarizeSelectedFiles.forEach(file => formData.append('files', file));
+  formData.append('style', style);
+  formData.append('language', language);
+
+  try {
+    const response = await fetch(`${API_URL}/summarize-file`, {
+      method: 'POST',
+      body: formData
+    });
+
+    const data = await response.json();
+    if (!response.ok) throw new Error(data.error || 'Summarization failed');
+
+    showResult('summarize-file-result', true, `
+      <h3>Summarization Complete!</h3>
+      <p>${data.successCount}/${data.totalFiles} files summarized</p>
+      <ul>${data.results.map(r => `
+        <li>
+          <span class="${r.success ? 'icon-success' : 'icon-error'}">${r.success ? '✓' : '✗'}</span>
+          ${r.fileName || r.filePath}
+          ${r.success && r.summaryUrl ? `<a href="${r.summaryUrl}" target="_blank">View</a>` : ''}
+          ${r.error ? `<small>(${r.error})</small>` : ''}
+        </li>
+      `).join('')}</ul>
+      ${data.results[0]?.summary ? `
+        <h4>Preview (first file):</h4>
+        <div class="summary-output">${data.results[0].summary.substring(0, 1000)}${data.results[0].summary.length > 1000 ? '...' : ''}</div>
+      ` : ''}
+    `);
+
+    summarizeSelectedFiles = [];
+    updateSummarizeFilesList();
+
+  } catch (error) {
+    showResult('summarize-file-result', false, `<h3>Error</h3><p>${error.message}</p>`);
+  } finally {
+    setLoading(button, false);
+  }
+});
+
+// ==================== SUMMARIZE LINK MODE (Full Pipeline) ====================
+
+const summarizeLinkForm = document.getElementById('summarize-link-form');
+if (summarizeLinkForm) {
+  const linkProgress = document.getElementById('summarize-link-progress');
+  const linkProgressFill = document.getElementById('summarize-link-progress-fill');
+  const linkProgressTitle = document.getElementById('summarize-link-progress-title');
+  const linkProgressPercent = document.getElementById('summarize-link-progress-percent');
+  const linkProgressPhase = document.getElementById('summarize-link-progress-phase');
+  const linkProgressSpeed = document.getElementById('summarize-link-progress-speed');
+  const linkProgressCurrent = document.getElementById('summarize-link-progress-current');
+  const linkProgressEta = document.getElementById('summarize-link-progress-eta');
+
+  function resetLinkProgress() {
+    if (linkProgressFill) linkProgressFill.style.width = '0%';
+    if (linkProgressPercent) linkProgressPercent.textContent = '0%';
+    if (linkProgressTitle) linkProgressTitle.textContent = 'Processing...';
+    if (linkProgressPhase) linkProgressPhase.textContent = '';
+    if (linkProgressSpeed) linkProgressSpeed.textContent = '';
+    if (linkProgressCurrent) linkProgressCurrent.textContent = '';
+    if (linkProgressEta) linkProgressEta.textContent = '';
+  }
+
+  summarizeLinkForm.addEventListener('submit', async (e) => {
+    e.preventDefault();
+    const button = document.getElementById('summarize-link-btn');
+    const url = document.getElementById('summarize-url').value;
+    const style = document.getElementById('summarize-link-style').value;
+    const language = document.getElementById('summarize-link-language').value;
+    const resultDiv = document.getElementById('summarize-link-result');
+
+    setLoading(button, true);
+    resetLinkProgress();
+    linkProgress.style.display = 'block';
+    resultDiv.classList.remove('show');
+
+    const params = new URLSearchParams({ url, style, language });
+    const eventSource = new EventSource(`${API_URL}/summarize-stream?${params}`);
+
+    eventSource.addEventListener('status', (e) => {
+      const data = JSON.parse(e.data);
+      linkProgressTitle.textContent = data.message;
+      if (data.percent !== undefined) {
+        linkProgressFill.style.width = `${data.percent}%`;
+        linkProgressPercent.textContent = `${Math.round(data.percent)}%`;
+      }
+    });
+
+    eventSource.addEventListener('info', (e) => {
+      const data = JSON.parse(e.data);
+      linkProgressTitle.textContent = data.totalVideos > 1
+        ? `Processing playlist: ${data.playlistTitle} (${data.totalVideos} videos)`
+        : `Processing: ${data.title}`;
+    });
+
+    eventSource.addEventListener('progress', (e) => {
+      const data = JSON.parse(e.data);
+      linkProgressFill.style.width = `${data.percent}%`;
+      linkProgressPercent.textContent = `${Math.round(data.percent)}%`;
+      linkProgressPhase.textContent = data.phaseLabel || '';
+      if (data.speed) linkProgressSpeed.textContent = data.speed;
+      if (data.title) {
+        linkProgressCurrent.innerHTML = `${data.phaseLabel}: <span class="video-title">${data.title}</span>`;
+      }
+      if (data.totalVideos > 1) {
+        linkProgressCurrent.innerHTML += ` (${data.currentVideo}/${data.totalVideos})`;
+      }
+    });
+
+    eventSource.addEventListener('video-complete', (e) => {
+      const data = JSON.parse(e.data);
+      linkProgressCurrent.innerHTML = `Downloaded: <span class="video-title">${data.title}</span>`;
+    });
+
+    eventSource.addEventListener('transcribe-complete', (e) => {
+      const data = JSON.parse(e.data);
+      linkProgressCurrent.innerHTML = `Transcribed: <span class="video-title">${data.title}</span>`;
+    });
+
+    eventSource.addEventListener('summarize-complete', (e) => {
+      const data = JSON.parse(e.data);
+      linkProgressCurrent.innerHTML = `Summarized: <span class="video-title">${data.title}</span>`;
+    });
+
+    eventSource.addEventListener('complete', (e) => {
+      const data = JSON.parse(e.data);
+      eventSource.close();
+      linkProgressFill.style.width = '100%';
+      linkProgressPercent.textContent = '100%';
+      linkProgressTitle.textContent = 'Complete!';
+      linkProgressPhase.textContent = '';
+      linkProgressEta.textContent = `Total: ${formatTime(data.totalTime)}`;
+
+      showResult('summarize-link-result', true, `
+        <h3>Pipeline Complete!</h3>
+        ${data.playlistTitle ? `<p>Playlist: ${data.playlistTitle}</p>` : ''}
+        <p>Downloaded: ${data.downloadedCount}/${data.totalVideos} | Transcribed: ${data.transcribedCount} | Summarized: ${data.summarizedCount}</p>
+        <ul>${data.results.map(r => `
+          <li>
+            <span class="${r.success ? 'icon-success' : 'icon-error'}">${r.success ? '✓' : '✗'}</span>
+            <strong>${r.title}</strong>
+            ${r.summaryUrl ? `<a href="${r.summaryUrl}" target="_blank">Summary</a>` : ''}
+            ${r.transcriptionUrl ? `<a href="${r.transcriptionUrl}" target="_blank">Transcript</a>` : ''}
+            ${r.error ? `<small>(${r.error})</small>` : ''}
+          </li>
+        `).join('')}</ul>
+        ${data.results[0]?.summary ? `
+          <h4>Summary Preview:</h4>
+          <div class="summary-output">${data.results[0].summary.substring(0, 2000)}${data.results[0].summary.length > 2000 ? '...' : ''}</div>
+        ` : ''}
+      `);
+      setLoading(button, false);
+    });
+
+    eventSource.addEventListener('error', (e) => {
+      let errorMsg = 'Processing failed';
+      try { errorMsg = JSON.parse(e.data).message || errorMsg; } catch {}
+      eventSource.close();
+      linkProgress.style.display = 'none';
+      showResult('summarize-link-result', false, `<h3>Error</h3><p>${errorMsg}</p>`);
+      setLoading(button, false);
+    });
+
+    eventSource.onerror = () => {
+      eventSource.close();
+      linkProgress.style.display = 'none';
+      showResult('summarize-link-result', false, `<h3>Error</h3><p>Connection lost</p>`);
+      setLoading(button, false);
+    };
+  });
+}
diff --git a/public/index.html b/public/index.html
index 4c009c7..43b9ed7 100644
--- a/public/index.html
+++ b/public/index.html
@@ -1,577 +1,577 @@
-<!DOCTYPE html>
-<html lang="fr">
-<head>
-  <meta charset="UTF-8">
-  <meta name="viewport" content="width=device-width, initial-scale=1.0">
-  <title>Video to MP3 Transcriptor</title>
-  <link rel="stylesheet" href="style.css">
-</head>
-<body>
-  <div class="container">
-    <header>
-      <h1>Video to MP3 Transcriptor</h1>
-      <p class="subtitle">Download YouTube videos, transcribe and translate them</p>
-    </header>
-
-    <!-- Tabs -->
-    <nav class="tabs">
-      <button class="tab active" data-tab="download">Download</button>
-      <button class="tab" data-tab="convert">Video to MP3</button>
-      <button class="tab" data-tab="transcribe">Transcribe</button>
-      <button class="tab" data-tab="process">Download + Transcribe</button>
-      <button class="tab" data-tab="translate">Translate</button>
-      <button class="tab" data-tab="summarize">Summarize</button>
-    </nav>
-
-    <!-- Download Tab -->
-    <section id="download" class="tab-content active">
-      <h2>Download YouTube Video/Playlist</h2>
-      <form id="download-form">
-        <div class="form-group">
-          <label for="download-url">YouTube URL</label>
-          <input type="url" id="download-url" placeholder="https://youtube.com/watch?v=..." required>
-        </div>
-        <button type="submit" class="btn btn-primary">
-          <span class="btn-text">Download MP3</span>
-          <span class="btn-loading">Downloading...</span>
-        </button>
-      </form>
-      <div id="download-progress" class="progress-container" style="display: none;">
-        <div class="progress-header">
-          <span id="progress-title">Downloading...</span>
-          <span id="progress-eta"></span>
-        </div>
-        <div class="progress-bar">
-          <div id="progress-fill" class="progress-fill"></div>
-        </div>
-        <div class="progress-details">
-          <span id="progress-percent">0%</span>
-          <span id="progress-info"></span>
-          <span id="progress-speed"></span>
-        </div>
-        <div id="progress-current" class="progress-current"></div>
-      </div>
-      <div id="download-result" class="result"></div>
-    </section>
-
-    <!-- Convert Tab -->
-    <section id="convert" class="tab-content">
-      <h2>Convert Video/Audio to MP3</h2>
-      <div id="convert-drop-zone" class="drop-zone">
-        <div class="drop-zone-content">
-          <div class="drop-zone-icon">
-            <svg xmlns="http://www.w3.org/2000/svg" width="48" height="48" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
-              <path d="M21 15v4a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2v-4"/>
-              <polyline points="17 8 12 3 7 8"/>
-              <line x1="12" y1="3" x2="12" y2="15"/>
-            </svg>
-          </div>
-          <p class="drop-zone-text">Drag & drop video/audio files here</p>
-          <p class="drop-zone-hint">or click to select files</p>
-          <p class="drop-zone-formats">Supported: MP4, M4A, AVI, MKV, MOV, WAV, FLAC, OGG</p>
-          <input type="file" id="convert-file-input" multiple accept="video/*,audio/*,.mp4,.avi,.mkv,.mov,.m4a,.wav,.flac,.ogg" style="display: none;">
-        </div>
-      </div>
-      <div id="convert-selected-files" class="selected-files" style="display: none;">
-        <h3>Selected Files</h3>
-        <ul id="convert-files-list"></ul>
-        <button type="button" id="convert-clear-files" class="btn btn-small btn-secondary">Clear</button>
-      </div>
-      <form id="convert-form">
-        <div class="form-row">
-          <div class="form-group">
-            <label for="convert-bitrate">Audio Bitrate</label>
-            <select id="convert-bitrate">
-              <option value="128k">128 kbps</option>
-              <option value="192k" selected>192 kbps (Recommended)</option>
-              <option value="256k">256 kbps</option>
-              <option value="320k">320 kbps (High Quality)</option>
-            </select>
-          </div>
-          <div class="form-group">
-            <label for="convert-quality">VBR Quality</label>
-            <select id="convert-quality">
-              <option value="0">0 - Best Quality</option>
-              <option value="2" selected>2 - High Quality</option>
-              <option value="4">4 - Standard</option>
-              <option value="6">6 - Good</option>
-            </select>
-          </div>
-        </div>
-        <button type="submit" class="btn btn-primary" id="convert-btn" disabled>
-          <span class="btn-text">Convert to MP3</span>
-          <span class="btn-loading">Converting...</span>
-        </button>
-      </form>
-      <div id="convert-progress" class="progress-container" style="display: none;">
-        <div class="progress-header">
-          <span id="convert-progress-title">Converting...</span>
-          <span id="convert-progress-info"></span>
-        </div>
-        <div class="progress-bar">
-          <div id="convert-progress-fill" class="progress-fill"></div>
-        </div>
-        <div class="progress-details">
-          <span id="convert-progress-percent">0%</span>
-          <span id="convert-progress-current"></span>
-        </div>
-      </div>
-      <div id="convert-result" class="result"></div>
-    </section>
-
-    <!-- Transcribe Tab -->
-    <section id="transcribe" class="tab-content">
-      <h2>Transcribe Audio File</h2>
-      <div id="drop-zone" class="drop-zone">
-        <div class="drop-zone-content">
-          <div class="drop-zone-icon">
-            <svg xmlns="http://www.w3.org/2000/svg" width="48" height="48" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
-              <path d="M21 15v4a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2v-4"/>
-              <polyline points="17 8 12 3 7 8"/>
-              <line x1="12" y1="3" x2="12" y2="15"/>
-            </svg>
-          </div>
-          <p class="drop-zone-text">Drag & drop audio files here</p>
-          <p class="drop-zone-hint">or click to select files</p>
-          <input type="file" id="file-input" multiple accept="audio/*,.mp3,.wav,.m4a,.ogg,.flac" style="display: none;">
-        </div>
-      </div>
-      <div id="selected-files" class="selected-files" style="display: none;">
-        <h3>Selected Files</h3>
-        <ul id="files-list"></ul>
-        <button type="button" id="clear-files" class="btn btn-small btn-secondary">Clear</button>
-      </div>
-      <form id="transcribe-form">
-        <div class="form-row">
-          <div class="form-group">
-            <label for="transcribe-lang">Language</label>
-            <select id="transcribe-lang">
-              <option value="">Auto-detect</option>
-              <option value="en">English</option>
-              <option value="fr">French</option>
-              <option value="es">Spanish</option>
-              <option value="de">German</option>
-              <option value="it">Italian</option>
-              <option value="pt">Portuguese</option>
-              <option value="zh">Chinese</option>
-              <option value="ja">Japanese</option>
-              <option value="ko">Korean</option>
-              <option value="ru">Russian</option>
-            </select>
-          </div>
-          <div class="form-group">
-            <label for="transcribe-model">Model</label>
-            <select id="transcribe-model">
-              <option value="gpt-4o-transcribe">gpt-4o-transcribe (Best)</option>
-              <option value="gpt-4o-mini-transcribe">gpt-4o-mini-transcribe (Faster)</option>
-              <option value="whisper-1">whisper-1 (Legacy)</option>
-            </select>
-          </div>
-        </div>
-        <!-- Translate option -->
-        <div class="form-group checkbox-group">
-          <label class="checkbox-label">
-            <input type="checkbox" id="transcribe-translate">
-            <span>Translate after transcription (GPT-4o-mini)</span>
-          </label>
-          <select id="transcribe-translate-lang" class="translate-lang-select" disabled>
-            <option value="en">English</option>
-            <option value="fr">French</option>
-            <option value="es">Spanish</option>
-            <option value="de">German</option>
-            <option value="it">Italian</option>
-            <option value="pt">Portuguese</option>
-            <option value="zh">Chinese</option>
-            <option value="ja">Japanese</option>
-            <option value="ko">Korean</option>
-            <option value="ru">Russian</option>
-          </select>
-        </div>
-        <button type="submit" class="btn btn-primary" id="transcribe-btn" disabled>
-          <span class="btn-text">Transcribe</span>
-          <span class="btn-loading">Transcribing...</span>
-        </button>
-      </form>
-      <div id="transcribe-progress" class="progress-container" style="display: none;">
-        <div class="progress-header">
-          <span id="transcribe-progress-title">Transcribing...</span>
-          <span id="transcribe-progress-info"></span>
-        </div>
-        <div class="progress-bar">
-          <div id="transcribe-progress-fill" class="progress-fill"></div>
-        </div>
-        <div class="progress-details">
-          <span id="transcribe-progress-percent">0%</span>
-          <span id="transcribe-progress-current"></span>
-        </div>
-      </div>
-      <div id="transcribe-result" class="result"></div>
-    </section>
-
-    <!-- Process Tab -->
-    <section id="process" class="tab-content">
-      <h2>Download + Transcribe</h2>
-      <form id="process-form">
-        <div class="form-group">
-          <label for="process-url">YouTube URL</label>
-          <input type="url" id="process-url" placeholder="https://youtube.com/watch?v=..." required>
-        </div>
-        <div class="form-row">
-          <div class="form-group">
-            <label for="process-lang">Language</label>
-            <select id="process-lang">
-              <option value="">Auto-detect</option>
-              <option value="en">English</option>
-              <option value="fr">French</option>
-              <option value="es">Spanish</option>
-              <option value="de">German</option>
-              <option value="it">Italian</option>
-              <option value="pt">Portuguese</option>
-              <option value="zh">Chinese</option>
-              <option value="ja">Japanese</option>
-              <option value="ko">Korean</option>
-              <option value="ru">Russian</option>
-            </select>
-          </div>
-          <div class="form-group">
-            <label for="process-model">Model</label>
-            <select id="process-model">
-              <option value="gpt-4o-transcribe">gpt-4o-transcribe (Best)</option>
-              <option value="gpt-4o-mini-transcribe">gpt-4o-mini-transcribe (Faster)</option>
-              <option value="whisper-1">whisper-1 (Legacy)</option>
-            </select>
-          </div>
-        </div>
-        <!-- Translate option -->
-        <div class="form-group checkbox-group">
-          <label class="checkbox-label">
-            <input type="checkbox" id="process-translate">
-            <span>Translate after transcription (GPT-4o-mini)</span>
-          </label>
-          <select id="process-translate-lang" class="translate-lang-select" disabled>
-            <option value="en">English</option>
-            <option value="fr">French</option>
-            <option value="es">Spanish</option>
-            <option value="de">German</option>
-            <option value="it">Italian</option>
-            <option value="pt">Portuguese</option>
-            <option value="zh">Chinese</option>
-            <option value="ja">Japanese</option>
-            <option value="ko">Korean</option>
-            <option value="ru">Russian</option>
-          </select>
-        </div>
-        <button type="submit" class="btn btn-primary">
-          <span class="btn-text">Download + Transcribe</span>
-          <span class="btn-loading">Processing...</span>
-        </button>
-      </form>
-      <div id="process-progress" class="progress-container" style="display: none;">
-        <div class="progress-header">
-          <span id="process-progress-title">Processing...</span>
-          <span id="process-progress-eta"></span>
-        </div>
-        <div class="progress-bar">
-          <div id="process-progress-fill" class="progress-fill"></div>
-        </div>
-        <div class="progress-details">
-          <span id="process-progress-percent">0%</span>
-          <span id="process-progress-phase"></span>
-          <span id="process-progress-speed"></span>
-        </div>
-        <div id="process-progress-current" class="progress-current"></div>
-      </div>
-      <div id="process-result" class="result"></div>
-    </section>
-
-    <!-- Translate Tab -->
-    <section id="translate" class="tab-content">
-      <h2>Translate Text</h2>
-
-      <!-- Mode selector -->
-      <div class="translate-mode-selector">
-        <button type="button" class="mode-btn active" data-mode="text">Text</button>
-        <button type="button" class="mode-btn" data-mode="file">Files</button>
-      </div>
-
-      <!-- Text mode -->
-      <div id="translate-text-mode" class="translate-mode">
-        <form id="translate-text-form">
-          <div class="form-group">
-            <label for="translate-input">Text to translate</label>
-            <textarea id="translate-input" rows="8" placeholder="Enter text to translate..."></textarea>
-          </div>
-          <div class="form-row">
-            <div class="form-group">
-              <label for="translate-source">Source language</label>
-              <select id="translate-source">
-                <option value="">Auto-detect</option>
-                <option value="en">English</option>
-                <option value="fr">French</option>
-                <option value="es">Spanish</option>
-                <option value="de">German</option>
-                <option value="it">Italian</option>
-                <option value="pt">Portuguese</option>
-                <option value="zh">Chinese</option>
-                <option value="ja">Japanese</option>
-                <option value="ko">Korean</option>
-                <option value="ru">Russian</option>
-              </select>
-            </div>
-            <div class="form-group">
-              <label for="translate-target">Target language</label>
-              <select id="translate-target" required>
-                <option value="en">English</option>
-                <option value="fr">French</option>
-                <option value="es">Spanish</option>
-                <option value="de">German</option>
-                <option value="it">Italian</option>
-                <option value="pt">Portuguese</option>
-                <option value="zh">Chinese</option>
-                <option value="ja">Japanese</option>
-                <option value="ko">Korean</option>
-                <option value="ru">Russian</option>
-              </select>
-            </div>
-          </div>
-          <button type="submit" class="btn btn-primary" id="translate-text-btn">
-            <span class="btn-text">Translate</span>
-            <span class="btn-loading">Translating...</span>
-          </button>
-        </form>
-        <div id="translate-text-result" class="result"></div>
-      </div>
-
-      <!-- File mode -->
-      <div id="translate-file-mode" class="translate-mode" style="display: none;">
-        <div id="translate-drop-zone" class="drop-zone">
-          <div class="drop-zone-content">
-            <div class="drop-zone-icon">
-              <svg xmlns="http://www.w3.org/2000/svg" width="48" height="48" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
-                <path d="M21 15v4a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2v-4"/>
-                <polyline points="17 8 12 3 7 8"/>
-                <line x1="12" y1="3" x2="12" y2="15"/>
-              </svg>
-            </div>
-            <p class="drop-zone-text">Drag & drop text files here</p>
-            <p class="drop-zone-hint">or click to select files (.txt)</p>
-            <input type="file" id="translate-file-input" multiple accept=".txt,text/plain" style="display: none;">
-          </div>
-        </div>
-        <div id="translate-selected-files" class="selected-files" style="display: none;">
-          <h3>Selected Files</h3>
-          <ul id="translate-files-list"></ul>
-          <button type="button" id="translate-clear-files" class="btn btn-small btn-secondary">Clear</button>
-        </div>
-        <form id="translate-file-form">
-          <div class="form-row">
-            <div class="form-group">
-              <label for="translate-file-source">Source language</label>
-              <select id="translate-file-source">
-                <option value="">Auto-detect</option>
-                <option value="en">English</option>
-                <option value="fr">French</option>
-                <option value="es">Spanish</option>
-                <option value="de">German</option>
-                <option value="it">Italian</option>
-                <option value="pt">Portuguese</option>
-                <option value="zh">Chinese</option>
-                <option value="ja">Japanese</option>
-                <option value="ko">Korean</option>
-                <option value="ru">Russian</option>
-              </select>
-            </div>
-            <div class="form-group">
-              <label for="translate-file-target">Target language</label>
-              <select id="translate-file-target" required>
-                <option value="en">English</option>
-                <option value="fr">French</option>
-                <option value="es">Spanish</option>
-                <option value="de">German</option>
-                <option value="it">Italian</option>
-                <option value="pt">Portuguese</option>
-                <option value="zh">Chinese</option>
-                <option value="ja">Japanese</option>
-                <option value="ko">Korean</option>
-                <option value="ru">Russian</option>
-              </select>
-            </div>
-          </div>
-          <button type="submit" class="btn btn-primary" id="translate-file-btn" disabled>
-            <span class="btn-text">Translate Files</span>
-            <span class="btn-loading">Translating...</span>
-          </button>
-        </form>
-        <div id="translate-file-result" class="result"></div>
-      </div>
-    </section>
-
-    <!-- Summarize Tab -->
-    <section id="summarize" class="tab-content">
-      <h2>Summarize Text (GPT-5.1)</h2>
-
-      <!-- Mode selector -->
-      <div class="summarize-mode-selector">
-        <button type="button" class="mode-btn active" data-mode="text">Text</button>
-        <button type="button" class="mode-btn" data-mode="file">Files</button>
-        <button type="button" class="mode-btn" data-mode="link">YouTube Link</button>
-      </div>
-
-      <!-- Text mode -->
-      <div id="summarize-text-mode" class="summarize-mode">
-        <form id="summarize-text-form">
-          <div class="form-group">
-            <label for="summarize-input">Text to summarize</label>
-            <textarea id="summarize-input" rows="8" placeholder="Enter text to summarize..."></textarea>
-          </div>
-          <div class="form-row">
-            <div class="form-group">
-              <label for="summarize-style">Style</label>
-              <select id="summarize-style">
-                <option value="concise">Concise</option>
-                <option value="detailed">Detailed</option>
-                <option value="bullet">Bullet Points</option>
-              </select>
-            </div>
-            <div class="form-group">
-              <label for="summarize-language">Output Language</label>
-              <select id="summarize-language">
-                <option value="same">Same as input</option>
-                <option value="en">English</option>
-                <option value="fr">French</option>
-                <option value="es">Spanish</option>
-                <option value="de">German</option>
-                <option value="it">Italian</option>
-                <option value="pt">Portuguese</option>
-                <option value="zh">Chinese</option>
-                <option value="ja">Japanese</option>
-                <option value="ko">Korean</option>
-                <option value="ru">Russian</option>
-              </select>
-            </div>
-          </div>
-          <button type="submit" class="btn btn-primary" id="summarize-text-btn">
-            <span class="btn-text">Summarize</span>
-            <span class="btn-loading">Summarizing...</span>
-          </button>
-        </form>
-        <div id="summarize-text-result" class="result"></div>
-      </div>
-
-      <!-- File mode -->
-      <div id="summarize-file-mode" class="summarize-mode" style="display: none;">
-        <div id="summarize-drop-zone" class="drop-zone">
-          <div class="drop-zone-content">
-            <div class="drop-zone-icon">
-              <svg xmlns="http://www.w3.org/2000/svg" width="48" height="48" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
-                <path d="M21 15v4a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2v-4"/>
-                <polyline points="17 8 12 3 7 8"/>
-                <line x1="12" y1="3" x2="12" y2="15"/>
-              </svg>
-            </div>
-            <p class="drop-zone-text">Drag & drop text files here</p>
-            <p class="drop-zone-hint">or click to select files (.txt)</p>
-            <input type="file" id="summarize-file-input" multiple accept=".txt,text/plain" style="display: none;">
-          </div>
-        </div>
-        <div id="summarize-selected-files" class="selected-files" style="display: none;">
-          <h3>Selected Files</h3>
-          <ul id="summarize-files-list"></ul>
-          <button type="button" id="summarize-clear-files" class="btn btn-small btn-secondary">Clear</button>
-        </div>
-        <form id="summarize-file-form">
-          <div class="form-row">
-            <div class="form-group">
-              <label for="summarize-file-style">Style</label>
-              <select id="summarize-file-style">
-                <option value="concise">Concise</option>
-                <option value="detailed">Detailed</option>
-                <option value="bullet">Bullet Points</option>
-              </select>
-            </div>
-            <div class="form-group">
-              <label for="summarize-file-language">Output Language</label>
-              <select id="summarize-file-language">
-                <option value="same">Same as input</option>
-                <option value="en">English</option>
-                <option value="fr">French</option>
-                <option value="es">Spanish</option>
-                <option value="de">German</option>
-                <option value="it">Italian</option>
-                <option value="pt">Portuguese</option>
-                <option value="zh">Chinese</option>
-                <option value="ja">Japanese</option>
-                <option value="ko">Korean</option>
-                <option value="ru">Russian</option>
-              </select>
-            </div>
-          </div>
-          <button type="submit" class="btn btn-primary" id="summarize-file-btn" disabled>
-            <span class="btn-text">Summarize Files</span>
-            <span class="btn-loading">Summarizing...</span>
-          </button>
-        </form>
-        <div id="summarize-file-result" class="result"></div>
-      </div>
-
-      <!-- Link mode (YouTube) -->
-      <div id="summarize-link-mode" class="summarize-mode" style="display: none;">
-        <form id="summarize-link-form">
-          <div class="form-group">
-            <label for="summarize-url">YouTube URL (video or playlist)</label>
-            <input type="url" id="summarize-url" placeholder="https://youtube.com/watch?v=..." required>
-          </div>
-          <div class="form-row">
-            <div class="form-group">
-              <label for="summarize-link-style">Summary Style</label>
-              <select id="summarize-link-style">
-                <option value="concise">Concise</option>
-                <option value="detailed">Detailed</option>
-                <option value="bullet">Bullet Points</option>
-              </select>
-            </div>
-            <div class="form-group">
-              <label for="summarize-link-language">Output Language</label>
-              <select id="summarize-link-language">
-                <option value="same">Same as video</option>
-                <option value="en">English</option>
-                <option value="fr">French</option>
-                <option value="es">Spanish</option>
-                <option value="de">German</option>
-                <option value="it">Italian</option>
-                <option value="pt">Portuguese</option>
-                <option value="zh">Chinese</option>
-                <option value="ja">Japanese</option>
-                <option value="ko">Korean</option>
-                <option value="ru">Russian</option>
-              </select>
-            </div>
-          </div>
-          <button type="submit" class="btn btn-primary" id="summarize-link-btn">
-            <span class="btn-text">Download + Transcribe + Summarize</span>
-            <span class="btn-loading">Processing...</span>
-          </button>
-        </form>
-        <div id="summarize-link-progress" class="progress-container" style="display: none;">
-          <div class="progress-header">
-            <span id="summarize-link-progress-title">Processing...</span>
-            <span id="summarize-link-progress-eta"></span>
-          </div>
-          <div class="progress-bar">
-            <div id="summarize-link-progress-fill" class="progress-fill"></div>
-          </div>
-          <div class="progress-details">
-            <span id="summarize-link-progress-percent">0%</span>
-            <span id="summarize-link-progress-phase"></span>
-            <span id="summarize-link-progress-speed"></span>
-          </div>
-          <div id="summarize-link-progress-current" class="progress-current"></div>
-        </div>
-        <div id="summarize-link-result" class="result"></div>
-      </div>
-    </section>
-  </div>
-
-  <script src="app.js"></script>
-</body>
-</html>
+<!DOCTYPE html>
+<html lang="fr">
+<head>
+  <meta charset="UTF-8">
+  <meta name="viewport" content="width=device-width, initial-scale=1.0">
+  <title>Video to MP3 Transcriptor</title>
+  <link rel="stylesheet" href="style.css">
+</head>
+<body>
+  <div class="container">
+    <header>
+      <h1>Video to MP3 Transcriptor</h1>
+      <p class="subtitle">Download YouTube videos, transcribe and translate them</p>
+    </header>
+
+    <!-- Tabs -->
+    <nav class="tabs">
+      <button class="tab active" data-tab="download">Download</button>
+      <button class="tab" data-tab="convert">Video to MP3</button>
+      <button class="tab" data-tab="transcribe">Transcribe</button>
+      <button class="tab" data-tab="process">Download + Transcribe</button>
+      <button class="tab" data-tab="translate">Translate</button>
+      <button class="tab" data-tab="summarize">Summarize</button>
+    </nav>
+
+    <!-- Download Tab -->
+    <section id="download" class="tab-content active">
+      <h2>Download YouTube Video/Playlist</h2>
+      <form id="download-form">
+        <div class="form-group">
+          <label for="download-url">YouTube URL</label>
+          <input type="url" id="download-url" placeholder="https://youtube.com/watch?v=..." required>
+        </div>
+        <button type="submit" class="btn btn-primary">
+          <span class="btn-text">Download MP3</span>
+          <span class="btn-loading">Downloading...</span>
+        </button>
+      </form>
+      <div id="download-progress" class="progress-container" style="display: none;">
+        <div class="progress-header">
+          <span id="progress-title">Downloading...</span>
+          <span id="progress-eta"></span>
+        </div>
+        <div class="progress-bar">
+          <div id="progress-fill" class="progress-fill"></div>
+        </div>
+        <div class="progress-details">
+          <span id="progress-percent">0%</span>
+          <span id="progress-info"></span>
+          <span id="progress-speed"></span>
+        </div>
+        <div id="progress-current" class="progress-current"></div>
+      </div>
+      <div id="download-result" class="result"></div>
+    </section>
+
+    <!-- Convert Tab -->
+    <section id="convert" class="tab-content">
+      <h2>Convert Video/Audio to MP3</h2>
+      <div id="convert-drop-zone" class="drop-zone">
+        <div class="drop-zone-content">
+          <div class="drop-zone-icon">
+            <svg xmlns="http://www.w3.org/2000/svg" width="48" height="48" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
+              <path d="M21 15v4a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2v-4"/>
+              <polyline points="17 8 12 3 7 8"/>
+              <line x1="12" y1="3" x2="12" y2="15"/>
+            </svg>
+          </div>
+          <p class="drop-zone-text">Drag & drop video/audio files here</p>
+          <p class="drop-zone-hint">or click to select files</p>
+          <p class="drop-zone-formats">Supported: MP4, M4A, AVI, MKV, MOV, WAV, FLAC, OGG</p>
+          <input type="file" id="convert-file-input" multiple accept="video/*,audio/*,.mp4,.avi,.mkv,.mov,.m4a,.wav,.flac,.ogg" style="display: none;">
+        </div>
+      </div>
+      <div id="convert-selected-files" class="selected-files" style="display: none;">
+        <h3>Selected Files</h3>
+        <ul id="convert-files-list"></ul>
+        <button type="button" id="convert-clear-files" class="btn btn-small btn-secondary">Clear</button>
+      </div>
+      <form id="convert-form">
+        <div class="form-row">
+          <div class="form-group">
+            <label for="convert-bitrate">Audio Bitrate</label>
+            <select id="convert-bitrate">
+              <option value="128k">128 kbps</option>
+              <option value="192k" selected>192 kbps (Recommended)</option>
+              <option value="256k">256 kbps</option>
+              <option value="320k">320 kbps (High Quality)</option>
+            </select>
+          </div>
+          <div class="form-group">
+            <label for="convert-quality">VBR Quality</label>
+            <select id="convert-quality">
+              <option value="0">0 - Best Quality</option>
+              <option value="2" selected>2 - High Quality</option>
+              <option value="4">4 - Standard</option>
+              <option value="6">6 - Good</option>
+            </select>
+          </div>
+        </div>
+        <button type="submit" class="btn btn-primary" id="convert-btn" disabled>
+          <span class="btn-text">Convert to MP3</span>
+          <span class="btn-loading">Converting...</span>
+        </button>
+      </form>
+      <div id="convert-progress" class="progress-container" style="display: none;">
+        <div class="progress-header">
+          <span id="convert-progress-title">Converting...</span>
+          <span id="convert-progress-info"></span>
+        </div>
+        <div class="progress-bar">
+          <div id="convert-progress-fill" class="progress-fill"></div>
+        </div>
+        <div class="progress-details">
+          <span id="convert-progress-percent">0%</span>
+          <span id="convert-progress-current"></span>
+        </div>
+      </div>
+      <div id="convert-result" class="result"></div>
+    </section>
+
+    <!-- Transcribe Tab -->
+    <section id="transcribe" class="tab-content">
+      <h2>Transcribe Audio File</h2>
+      <div id="drop-zone" class="drop-zone">
+        <div class="drop-zone-content">
+          <div class="drop-zone-icon">
+            <svg xmlns="http://www.w3.org/2000/svg" width="48" height="48" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
+              <path d="M21 15v4a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2v-4"/>
+              <polyline points="17 8 12 3 7 8"/>
+              <line x1="12" y1="3" x2="12" y2="15"/>
+            </svg>
+          </div>
+          <p class="drop-zone-text">Drag & drop audio files here</p>
+          <p class="drop-zone-hint">or click to select files</p>
+          <input type="file" id="file-input" multiple accept="audio/*,.mp3,.wav,.m4a,.ogg,.flac" style="display: none;">
+        </div>
+      </div>
+      <div id="selected-files" class="selected-files" style="display: none;">
+        <h3>Selected Files</h3>
+        <ul id="files-list"></ul>
+        <button type="button" id="clear-files" class="btn btn-small btn-secondary">Clear</button>
+      </div>
+      <form id="transcribe-form">
+        <div class="form-row">
+          <div class="form-group">
+            <label for="transcribe-lang">Language</label>
+            <select id="transcribe-lang">
+              <option value="">Auto-detect</option>
+              <option value="en">English</option>
+              <option value="fr">French</option>
+              <option value="es">Spanish</option>
+              <option value="de">German</option>
+              <option value="it">Italian</option>
+              <option value="pt">Portuguese</option>
+              <option value="zh">Chinese</option>
+              <option value="ja">Japanese</option>
+              <option value="ko">Korean</option>
+              <option value="ru">Russian</option>
+            </select>
+          </div>
+          <div class="form-group">
+            <label for="transcribe-model">Model</label>
+            <select id="transcribe-model">
+              <option value="gpt-4o-transcribe">gpt-4o-transcribe (Best)</option>
+              <option value="gpt-4o-mini-transcribe">gpt-4o-mini-transcribe (Faster)</option>
+              <option value="whisper-1">whisper-1 (Legacy)</option>
+            </select>
+          </div>
+        </div>
+        <!-- Translate option -->
+        <div class="form-group checkbox-group">
+          <label class="checkbox-label">
+            <input type="checkbox" id="transcribe-translate">
+            <span>Translate after transcription (GPT-4o-mini)</span>
+          </label>
+          <select id="transcribe-translate-lang" class="translate-lang-select" disabled>
+            <option value="en">English</option>
+            <option value="fr">French</option>
+            <option value="es">Spanish</option>
+            <option value="de">German</option>
+            <option value="it">Italian</option>
+            <option value="pt">Portuguese</option>
+            <option value="zh">Chinese</option>
+            <option value="ja">Japanese</option>
+            <option value="ko">Korean</option>
+            <option value="ru">Russian</option>
+          </select>
+        </div>
+        <button type="submit" class="btn btn-primary" id="transcribe-btn" disabled>
+          <span class="btn-text">Transcribe</span>
+          <span class="btn-loading">Transcribing...</span>
+        </button>
+      </form>
+      <div id="transcribe-progress" class="progress-container" style="display: none;">
+        <div class="progress-header">
+          <span id="transcribe-progress-title">Transcribing...</span>
+          <span id="transcribe-progress-info"></span>
+        </div>
+        <div class="progress-bar">
+          <div id="transcribe-progress-fill" class="progress-fill"></div>
+        </div>
+        <div class="progress-details">
+          <span id="transcribe-progress-percent">0%</span>
+          <span id="transcribe-progress-current"></span>
+        </div>
+      </div>
+      <div id="transcribe-result" class="result"></div>
+    </section>
+
+    <!-- Process Tab -->
+    <section id="process" class="tab-content">
+      <h2>Download + Transcribe</h2>
+      <form id="process-form">
+        <div class="form-group">
+          <label for="process-url">YouTube URL</label>
+          <input type="url" id="process-url" placeholder="https://youtube.com/watch?v=..." required>
+        </div>
+        <div class="form-row">
+          <div class="form-group">
+            <label for="process-lang">Language</label>
+            <select id="process-lang">
+              <option value="">Auto-detect</option>
+              <option value="en">English</option>
+              <option value="fr">French</option>
+              <option value="es">Spanish</option>
+              <option value="de">German</option>
+              <option value="it">Italian</option>
+              <option value="pt">Portuguese</option>
+              <option value="zh">Chinese</option>
+              <option value="ja">Japanese</option>
+              <option value="ko">Korean</option>
+              <option value="ru">Russian</option>
+            </select>
+          </div>
+          <div class="form-group">
+            <label for="process-model">Model</label>
+            <select id="process-model">
+              <option value="gpt-4o-transcribe">gpt-4o-transcribe (Best)</option>
+              <option value="gpt-4o-mini-transcribe">gpt-4o-mini-transcribe (Faster)</option>
+              <option value="whisper-1">whisper-1 (Legacy)</option>
+            </select>
+          </div>
+        </div>
+        <!-- Translate option -->
+        <div class="form-group checkbox-group">
+          <label class="checkbox-label">
+            <input type="checkbox" id="process-translate">
+            <span>Translate after transcription (GPT-4o-mini)</span>
+          </label>
+          <select id="process-translate-lang" class="translate-lang-select" disabled>
+            <option value="en">English</option>
+            <option value="fr">French</option>
+            <option value="es">Spanish</option>
+            <option value="de">German</option>
+            <option value="it">Italian</option>
+            <option value="pt">Portuguese</option>
+            <option value="zh">Chinese</option>
+            <option value="ja">Japanese</option>
+            <option value="ko">Korean</option>
+            <option value="ru">Russian</option>
+          </select>
+        </div>
+        <button type="submit" class="btn btn-primary">
+          <span class="btn-text">Download + Transcribe</span>
+          <span class="btn-loading">Processing...</span>
+        </button>
+      </form>
+      <div id="process-progress" class="progress-container" style="display: none;">
+        <div class="progress-header">
+          <span id="process-progress-title">Processing...</span>
+          <span id="process-progress-eta"></span>
+        </div>
+        <div class="progress-bar">
+          <div id="process-progress-fill" class="progress-fill"></div>
+        </div>
+        <div class="progress-details">
+          <span id="process-progress-percent">0%</span>
+          <span id="process-progress-phase"></span>
+          <span id="process-progress-speed"></span>
+        </div>
+        <div id="process-progress-current" class="progress-current"></div>
+      </div>
+      <div id="process-result" class="result"></div>
+    </section>
+
+    <!-- Translate Tab -->
+    <section id="translate" class="tab-content">
+      <h2>Translate Text</h2>
+
+      <!-- Mode selector -->
+      <div class="translate-mode-selector">
+        <button type="button" class="mode-btn active" data-mode="text">Text</button>
+        <button type="button" class="mode-btn" data-mode="file">Files</button>
+      </div>
+
+      <!-- Text mode -->
+      <div id="translate-text-mode" class="translate-mode">
+        <form id="translate-text-form">
+          <div class="form-group">
+            <label for="translate-input">Text to translate</label>
+            <textarea id="translate-input" rows="8" placeholder="Enter text to translate..."></textarea>
+          </div>
+          <div class="form-row">
+            <div class="form-group">
+              <label for="translate-source">Source language</label>
+              <select id="translate-source">
+                <option value="">Auto-detect</option>
+                <option value="en">English</option>
+                <option value="fr">French</option>
+                <option value="es">Spanish</option>
+                <option value="de">German</option>
+                <option value="it">Italian</option>
+                <option value="pt">Portuguese</option>
+                <option value="zh">Chinese</option>
+                <option value="ja">Japanese</option>
+                <option value="ko">Korean</option>
+                <option value="ru">Russian</option>
+              </select>
+            </div>
+            <div class="form-group">
+              <label for="translate-target">Target language</label>
+              <select id="translate-target" required>
+                <option value="en">English</option>
+                <option value="fr">French</option>
+                <option value="es">Spanish</option>
+                <option value="de">German</option>
+                <option value="it">Italian</option>
+                <option value="pt">Portuguese</option>
+                <option value="zh">Chinese</option>
+                <option value="ja">Japanese</option>
+                <option value="ko">Korean</option>
+                <option value="ru">Russian</option>
+              </select>
+            </div>
+          </div>
+          <button type="submit" class="btn btn-primary" id="translate-text-btn">
+            <span class="btn-text">Translate</span>
+            <span class="btn-loading">Translating...</span>
+          </button>
+        </form>
+        <div id="translate-text-result" class="result"></div>
+      </div>
+
+      <!-- File mode -->
+      <div id="translate-file-mode" class="translate-mode" style="display: none;">
+        <div id="translate-drop-zone" class="drop-zone">
+          <div class="drop-zone-content">
+            <div class="drop-zone-icon">
+              <svg xmlns="http://www.w3.org/2000/svg" width="48" height="48" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
+                <path d="M21 15v4a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2v-4"/>
+                <polyline points="17 8 12 3 7 8"/>
+                <line x1="12" y1="3" x2="12" y2="15"/>
+              </svg>
+            </div>
+            <p class="drop-zone-text">Drag & drop text files here</p>
+            <p class="drop-zone-hint">or click to select files (.txt)</p>
+            <input type="file" id="translate-file-input" multiple accept=".txt,text/plain" style="display: none;">
+          </div>
+        </div>
+        <div id="translate-selected-files" class="selected-files" style="display: none;">
+          <h3>Selected Files</h3>
+          <ul id="translate-files-list"></ul>
+          <button type="button" id="translate-clear-files" class="btn btn-small btn-secondary">Clear</button>
+        </div>
+        <form id="translate-file-form">
+          <div class="form-row">
+            <div class="form-group">
+              <label for="translate-file-source">Source language</label>
+              <select id="translate-file-source">
+                <option value="">Auto-detect</option>
+                <option value="en">English</option>
+                <option value="fr">French</option>
+                <option value="es">Spanish</option>
+                <option value="de">German</option>
+                <option value="it">Italian</option>
+                <option value="pt">Portuguese</option>
+                <option value="zh">Chinese</option>
+                <option value="ja">Japanese</option>
+                <option value="ko">Korean</option>
+                <option value="ru">Russian</option>
+              </select>
+            </div>
+            <div class="form-group">
+              <label for="translate-file-target">Target language</label>
+              <select id="translate-file-target" required>
+                <option value="en">English</option>
+                <option value="fr">French</option>
+                <option value="es">Spanish</option>
+                <option value="de">German</option>
+                <option value="it">Italian</option>
+                <option value="pt">Portuguese</option>
+                <option value="zh">Chinese</option>
+                <option value="ja">Japanese</option>
+                <option value="ko">Korean</option>
+                <option value="ru">Russian</option>
+              </select>
+            </div>
+          </div>
+          <button type="submit" class="btn btn-primary" id="translate-file-btn" disabled>
+            <span class="btn-text">Translate Files</span>
+            <span class="btn-loading">Translating...</span>
+          </button>
+        </form>
+        <div id="translate-file-result" class="result"></div>
+      </div>
+    </section>
+
+    <!-- Summarize Tab -->
+    <section id="summarize" class="tab-content">
+      <h2>Summarize Text (GPT-5.1)</h2>
+
+      <!-- Mode selector -->
+      <div class="summarize-mode-selector">
+        <button type="button" class="mode-btn active" data-mode="text">Text</button>
+        <button type="button" class="mode-btn" data-mode="file">Files</button>
+        <button type="button" class="mode-btn" data-mode="link">YouTube Link</button>
+      </div>
+
+      <!-- Text mode -->
+      <div id="summarize-text-mode" class="summarize-mode">
+        <form id="summarize-text-form">
+          <div class="form-group">
+            <label for="summarize-input">Text to summarize</label>
+            <textarea id="summarize-input" rows="8" placeholder="Enter text to summarize..."></textarea>
+          </div>
+          <div class="form-row">
+            <div class="form-group">
+              <label for="summarize-style">Style</label>
+              <select id="summarize-style">
+                <option value="concise">Concise</option>
+                <option value="detailed">Detailed</option>
+                <option value="bullet">Bullet Points</option>
+              </select>
+            </div>
+            <div class="form-group">
+              <label for="summarize-language">Output Language</label>
+              <select id="summarize-language">
+                <option value="same">Same as input</option>
+                <option value="en">English</option>
+                <option value="fr">French</option>
+                <option value="es">Spanish</option>
+                <option value="de">German</option>
+                <option value="it">Italian</option>
+                <option value="pt">Portuguese</option>
+                <option value="zh">Chinese</option>
+                <option value="ja">Japanese</option>
+                <option value="ko">Korean</option>
+                <option value="ru">Russian</option>
+              </select>
+            </div>
+          </div>
+          <button type="submit" class="btn btn-primary" id="summarize-text-btn">
+            <span class="btn-text">Summarize</span>
+            <span class="btn-loading">Summarizing...</span>
+          </button>
+        </form>
+        <div id="summarize-text-result" class="result"></div>
+      </div>
+
+      <!-- File mode -->
+      <div id="summarize-file-mode" class="summarize-mode" style="display: none;">
+        <div id="summarize-drop-zone" class="drop-zone">
+          <div class="drop-zone-content">
+            <div class="drop-zone-icon">
+              <svg xmlns="http://www.w3.org/2000/svg" width="48" height="48" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round">
+                <path d="M21 15v4a2 2 0 0 1-2 2H5a2 2 0 0 1-2-2v-4"/>
+                <polyline points="17 8 12 3 7 8"/>
+                <line x1="12" y1="3" x2="12" y2="15"/>
+              </svg>
+            </div>
+            <p class="drop-zone-text">Drag & drop text files here</p>
+            <p class="drop-zone-hint">or click to select files (.txt)</p>
+            <input type="file" id="summarize-file-input" multiple accept=".txt,text/plain" style="display: none;">
+          </div>
+        </div>
+        <div id="summarize-selected-files" class="selected-files" style="display: none;">
+          <h3>Selected Files</h3>
+          <ul id="summarize-files-list"></ul>
+          <button type="button" id="summarize-clear-files" class="btn btn-small btn-secondary">Clear</button>
+        </div>
+        <form id="summarize-file-form">
+          <div class="form-row">
+            <div class="form-group">
+              <label for="summarize-file-style">Style</label>
+              <select id="summarize-file-style">
+                <option value="concise">Concise</option>
+                <option value="detailed">Detailed</option>
+                <option value="bullet">Bullet Points</option>
+              </select>
+            </div>
+            <div class="form-group">
+              <label for="summarize-file-language">Output Language</label>
+              <select id="summarize-file-language">
+                <option value="same">Same as input</option>
+                <option value="en">English</option>
+                <option value="fr">French</option>
+                <option value="es">Spanish</option>
+                <option value="de">German</option>
+                <option value="it">Italian</option>
+                <option value="pt">Portuguese</option>
+                <option value="zh">Chinese</option>
+                <option value="ja">Japanese</option>
+                <option value="ko">Korean</option>
+                <option value="ru">Russian</option>
+              </select>
+            </div>
+          </div>
+          <button type="submit" class="btn btn-primary" id="summarize-file-btn" disabled>
+            <span class="btn-text">Summarize Files</span>
+            <span class="btn-loading">Summarizing...</span>
+          </button>
+        </form>
+        <div id="summarize-file-result" class="result"></div>
+      </div>
+
+      <!-- Link mode (YouTube) -->
+      <div id="summarize-link-mode" class="summarize-mode" style="display: none;">
+        <form id="summarize-link-form">
+          <div class="form-group">
+            <label for="summarize-url">YouTube URL (video or playlist)</label>
+            <input type="url" id="summarize-url" placeholder="https://youtube.com/watch?v=..." required>
+          </div>
+          <div class="form-row">
+            <div class="form-group">
+              <label for="summarize-link-style">Summary Style</label>
+              <select id="summarize-link-style">
+                <option value="concise">Concise</option>
+                <option value="detailed">Detailed</option>
+                <option value="bullet">Bullet Points</option>
+              </select>
+            </div>
+            <div class="form-group">
+              <label for="summarize-link-language">Output Language</label>
+              <select id="summarize-link-language">
+                <option value="same">Same as video</option>
+                <option value="en">English</option>
+                <option value="fr">French</option>
+                <option value="es">Spanish</option>
+                <option value="de">German</option>
+                <option value="it">Italian</option>
+                <option value="pt">Portuguese</option>
+                <option value="zh">Chinese</option>
+                <option value="ja">Japanese</option>
+                <option value="ko">Korean</option>
+                <option value="ru">Russian</option>
+              </select>
+            </div>
+          </div>
+          <button type="submit" class="btn btn-primary" id="summarize-link-btn">
+            <span class="btn-text">Download + Transcribe + Summarize</span>
+            <span class="btn-loading">Processing...</span>
+          </button>
+        </form>
+        <div id="summarize-link-progress" class="progress-container" style="display: none;">
+          <div class="progress-header">
+            <span id="summarize-link-progress-title">Processing...</span>
+            <span id="summarize-link-progress-eta"></span>
+          </div>
+          <div class="progress-bar">
+            <div id="summarize-link-progress-fill" class="progress-fill"></div>
+          </div>
+          <div class="progress-details">
+            <span id="summarize-link-progress-percent">0%</span>
+            <span id="summarize-link-progress-phase"></span>
+            <span id="summarize-link-progress-speed"></span>
+          </div>
+          <div id="summarize-link-progress-current" class="progress-current"></div>
+        </div>
+        <div id="summarize-link-result" class="result"></div>
+      </div>
+    </section>
+  </div>
+
+  <script src="app.js"></script>
+</body>
+</html>
diff --git a/public/style.css b/public/style.css
index 9d5d9e1..d9b3f34 100644
--- a/public/style.css
+++ b/public/style.css
@@ -1,716 +1,716 @@
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-  margin: 0;
-  padding: 0;
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-  background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
-  min-height: 100vh;
-  color: #fff;
-}
-
-.container {
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-  margin: 0 auto;
-  padding: 2rem;
-}
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-header {
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-  margin-bottom: 2rem;
-}
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-header h1 {
-  font-size: 2.5rem;
-  background: linear-gradient(90deg, #e94560, #0f3460);
-  -webkit-background-clip: text;
-  -webkit-text-fill-color: transparent;
-  background-clip: text;
-}
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-.subtitle {
-  color: #8892b0;
-  margin-top: 0.5rem;
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-.tabs {
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-.tab {
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-.tab:hover {
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-.tab.active {
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-/* Tab Content */
-.tab-content {
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-.tab-content.active {
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-.tab-content h2 {
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-.form-group label {
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-.form-row {
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-@media (max-width: 600px) {
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-  }
-}
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-input[type="url"],
-input[type="text"],
-select {
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-  padding: 0.75rem 1rem;
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-.btn {
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-.btn-primary {
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-.btn-primary:hover {
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-.btn-secondary {
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-.btn-small {
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-.btn-loading {
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-.result.show {
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-
-/* Drag and Drop Zone */
-.drop-zone {
-  border: 2px dashed #233554;
-  border-radius: 12px;
-  padding: 3rem 2rem;
-  text-align: center;
-  cursor: pointer;
-  transition: all 0.3s ease;
-  margin-bottom: 1.5rem;
-  background: rgba(255, 255, 255, 0.02);
-}
-
-.drop-zone:hover {
-  border-color: #e94560;
-  background: rgba(233, 69, 96, 0.05);
-}
-
-.drop-zone.drag-over {
-  border-color: #e94560;
-  background: rgba(233, 69, 96, 0.1);
-  transform: scale(1.02);
-}
-
-.drop-zone-icon {
-  color: #8892b0;
-  margin-bottom: 1rem;
-  transition: color 0.3s ease;
-}
-
-.drop-zone:hover .drop-zone-icon {
-  color: #e94560;
-}
-
-.drop-zone-text {
-  color: #ccd6f6;
-  font-size: 1.1rem;
-  margin-bottom: 0.5rem;
-}
-
-.drop-zone-hint {
-  color: #8892b0;
-  font-size: 0.9rem;
-}
-
-.drop-zone-formats {
-  color: #64748b;
-  font-size: 0.75rem;
-  margin-top: 0.5rem;
-  font-style: italic;
-}
-
-/* Selected Files List */
-.selected-files {
-  background: rgba(255, 255, 255, 0.05);
-  border-radius: 8px;
-  padding: 1rem;
-  margin-bottom: 1.5rem;
-}
-
-.selected-files h3 {
-  font-size: 0.9rem;
-  color: #8892b0;
-  margin-bottom: 0.75rem;
-  text-transform: uppercase;
-  letter-spacing: 0.5px;
-}
-
-.selected-files ul {
-  list-style: none;
-  margin-bottom: 1rem;
-}
-
-.selected-files li {
-  display: flex;
-  align-items: center;
-  justify-content: space-between;
-  padding: 0.5rem 0;
-  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
-  color: #ccd6f6;
-}
-
-.selected-files li:last-child {
-  border-bottom: none;
-}
-
-.selected-files .file-name {
-  flex: 1;
-  overflow: hidden;
-  text-overflow: ellipsis;
-  white-space: nowrap;
-}
-
-.selected-files .file-size {
-  color: #8892b0;
-  font-size: 0.85rem;
-  margin-left: 1rem;
-}
-
-.selected-files .remove-file {
-  background: none;
-  border: none;
-  color: #ef4444;
-  cursor: pointer;
-  padding: 0.25rem;
-  margin-left: 0.5rem;
-  font-size: 1.2rem;
-  line-height: 1;
-}
-
-.selected-files .remove-file:hover {
-  color: #ff6b6b;
-}
-
-/* Checkbox Group */
-.checkbox-group {
-  margin-bottom: 1rem;
-}
-
-.checkbox-label {
-  display: flex;
-  align-items: center;
-  gap: 0.5rem;
-  cursor: pointer;
-  color: #ccd6f6;
-  font-size: 0.95rem;
-}
-
-.checkbox-label input[type="checkbox"] {
-  width: 18px;
-  height: 18px;
-  accent-color: #e94560;
-  cursor: pointer;
-}
-
-.translate-lang-select {
-  margin-top: 0.75rem;
-  width: auto;
-  min-width: 150px;
-}
-
-.translate-lang-select:disabled {
-  opacity: 0.5;
-  cursor: not-allowed;
-}
-
-/* Translate Tab */
-.translate-mode-selector {
-  display: flex;
-  gap: 0.5rem;
-  margin-bottom: 1.5rem;
-}
-
-.mode-btn {
-  padding: 0.6rem 1.25rem;
-  background: rgba(255, 255, 255, 0.05);
-  border: 1px solid #233554;
-  color: #8892b0;
-  border-radius: 8px;
-  cursor: pointer;
-  font-size: 0.95rem;
-  transition: all 0.3s ease;
-}
-
-.mode-btn:hover {
-  border-color: #e94560;
-  color: #ccd6f6;
-}
-
-.mode-btn.active {
-  background: rgba(233, 69, 96, 0.2);
-  border-color: #e94560;
-  color: #e94560;
-}
-
-.translate-mode {
-  animation: fadeIn 0.3s ease;
-}
-
-/* Textarea */
-textarea {
-  width: 100%;
-  padding: 1rem;
-  background: rgba(255, 255, 255, 0.1);
-  border: 1px solid #233554;
-  border-radius: 8px;
-  color: #fff;
-  font-size: 1rem;
-  font-family: inherit;
-  resize: vertical;
-  min-height: 150px;
-  transition: all 0.3s ease;
-}
-
-textarea:focus {
-  outline: none;
-  border-color: #e94560;
-  background: rgba(233, 69, 96, 0.1);
-}
-
-textarea::placeholder {
-  color: #8892b0;
-}
-
-/* Translation Result */
-.translation-output {
-  margin-top: 1rem;
-  padding: 1rem;
-  background: rgba(0, 0, 0, 0.3);
-  border-radius: 8px;
-  white-space: pre-wrap;
-  max-height: 400px;
-  overflow-y: auto;
-  color: #ccd6f6;
-  line-height: 1.6;
-}
-
-/* Summarize Tab */
-.summarize-mode-selector {
-  display: flex;
-  gap: 0.5rem;
-  margin-bottom: 1.5rem;
-}
-
-.summarize-mode {
-  animation: fadeIn 0.3s ease;
-}
-
-/* Summary Result */
-.summary-output {
-  margin-top: 1rem;
-  padding: 1rem;
-  background: rgba(0, 0, 0, 0.3);
-  border-radius: 8px;
-  white-space: pre-wrap;
-  max-height: 400px;
-  overflow-y: auto;
-  color: #ccd6f6;
-  line-height: 1.6;
-}
+* {
+  margin: 0;
+  padding: 0;
+  box-sizing: border-box;
+}
+
+body {
+  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
+  background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
+  min-height: 100vh;
+  color: #fff;
+}
+
+.container {
+  max-width: 900px;
+  margin: 0 auto;
+  padding: 2rem;
+}
+
+header {
+  text-align: center;
+  margin-bottom: 2rem;
+}
+
+header h1 {
+  font-size: 2.5rem;
+  background: linear-gradient(90deg, #e94560, #0f3460);
+  -webkit-background-clip: text;
+  -webkit-text-fill-color: transparent;
+  background-clip: text;
+}
+
+.subtitle {
+  color: #8892b0;
+  margin-top: 0.5rem;
+}
+
+/* Tabs */
+.tabs {
+  display: flex;
+  gap: 0.5rem;
+  margin-bottom: 2rem;
+  border-bottom: 2px solid #233554;
+  padding-bottom: 0.5rem;
+  flex-wrap: wrap;
+}
+
+.tab {
+  padding: 0.75rem 1.5rem;
+  background: transparent;
+  border: none;
+  color: #8892b0;
+  cursor: pointer;
+  font-size: 1rem;
+  border-radius: 8px 8px 0 0;
+  transition: all 0.3s ease;
+}
+
+.tab:hover {
+  color: #e94560;
+  background: rgba(233, 69, 96, 0.1);
+}
+
+.tab.active {
+  color: #e94560;
+  background: rgba(233, 69, 96, 0.2);
+  border-bottom: 2px solid #e94560;
+  margin-bottom: -2px;
+}
+
+/* Tab Content */
+.tab-content {
+  display: none;
+  background: rgba(255, 255, 255, 0.05);
+  padding: 2rem;
+  border-radius: 12px;
+  backdrop-filter: blur(10px);
+}
+
+.tab-content.active {
+  display: block;
+  animation: fadeIn 0.3s ease;
+}
+
+@keyframes fadeIn {
+  from { opacity: 0; transform: translateY(10px); }
+  to { opacity: 1; transform: translateY(0); }
+}
+
+.tab-content h2 {
+  margin-bottom: 1.5rem;
+  color: #ccd6f6;
+}
+
+/* Forms */
+.form-group {
+  margin-bottom: 1.5rem;
+}
+
+.form-group label {
+  display: block;
+  margin-bottom: 0.5rem;
+  color: #8892b0;
+  font-size: 0.9rem;
+}
+
+.form-row {
+  display: grid;
+  grid-template-columns: 1fr 1fr;
+  gap: 1rem;
+}
+
+@media (max-width: 600px) {
+  .form-row {
+    grid-template-columns: 1fr;
+  }
+}
+
+input[type="url"],
+input[type="text"],
+select {
+  width: 100%;
+  padding: 0.75rem 1rem;
+  background: rgba(255, 255, 255, 0.1);
+  border: 1px solid #233554;
+  border-radius: 8px;
+  color: #fff;
+  font-size: 1rem;
+  transition: all 0.3s ease;
+}
+
+input[type="url"]:focus,
+input[type="text"]:focus,
+select:focus {
+  outline: none;
+  border-color: #e94560;
+  background: rgba(233, 69, 96, 0.1);
+}
+
+select option {
+  background: #1a1a2e;
+  color: #fff;
+}
+
+/* Buttons */
+.btn {
+  padding: 0.75rem 2rem;
+  border: none;
+  border-radius: 8px;
+  font-size: 1rem;
+  cursor: pointer;
+  transition: all 0.3s ease;
+  display: inline-flex;
+  align-items: center;
+  gap: 0.5rem;
+}
+
+.btn-primary {
+  background: linear-gradient(90deg, #e94560, #0f3460);
+  color: #fff;
+}
+
+.btn-primary:hover {
+  transform: translateY(-2px);
+  box-shadow: 0 5px 20px rgba(233, 69, 96, 0.4);
+}
+
+.btn-primary:disabled {
+  opacity: 0.6;
+  cursor: not-allowed;
+  transform: none;
+}
+
+.btn-secondary {
+  background: rgba(255, 255, 255, 0.1);
+  color: #ccd6f6;
+  border: 1px solid #233554;
+}
+
+.btn-secondary:hover {
+  background: rgba(255, 255, 255, 0.2);
+}
+
+.btn-small {
+  padding: 0.5rem 1rem;
+  font-size: 0.85rem;
+  margin-left: 0.5rem;
+}
+
+.btn-loading {
+  display: none;
+}
+
+.btn.loading .btn-text {
+  display: none;
+}
+
+.btn.loading .btn-loading {
+  display: inline;
+}
+
+/* Results */
+.result {
+  margin-top: 1.5rem;
+  padding: 1rem;
+  border-radius: 8px;
+  display: none;
+}
+
+.result.show {
+  display: block;
+  animation: fadeIn 0.3s ease;
+}
+
+.result.success {
+  background: rgba(16, 185, 129, 0.2);
+  border: 1px solid #10b981;
+}
+
+.result.error {
+  background: rgba(239, 68, 68, 0.2);
+  border: 1px solid #ef4444;
+}
+
+.result h3 {
+  margin-bottom: 0.75rem;
+  font-size: 1.1rem;
+}
+
+.result ul {
+  list-style: none;
+  margin-top: 0.5rem;
+}
+
+.result li {
+  padding: 0.5rem 0;
+  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
+  display: flex;
+  align-items: center;
+  gap: 0.5rem;
+}
+
+.result li:last-child {
+  border-bottom: none;
+}
+
+.result .icon-success {
+  color: #10b981;
+}
+
+.result .icon-error {
+  color: #ef4444;
+}
+
+.result a {
+  color: #e94560;
+  text-decoration: none;
+}
+
+.result a:hover {
+  text-decoration: underline;
+}
+
+.result .preview {
+  margin-top: 1rem;
+  padding: 1rem;
+  background: rgba(0, 0, 0, 0.3);
+  border-radius: 8px;
+  font-family: monospace;
+  font-size: 0.9rem;
+  white-space: pre-wrap;
+  max-height: 300px;
+  overflow-y: auto;
+}
+
+/* Files Grid */
+.files-grid {
+  display: grid;
+  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
+  gap: 1rem;
+  margin-top: 1.5rem;
+}
+
+.file-card {
+  background: rgba(255, 255, 255, 0.05);
+  padding: 1rem;
+  border-radius: 8px;
+  border: 1px solid #233554;
+  transition: all 0.3s ease;
+}
+
+.file-card:hover {
+  border-color: #e94560;
+  transform: translateY(-2px);
+}
+
+.file-card .file-name {
+  font-weight: 600;
+  margin-bottom: 0.5rem;
+  word-break: break-all;
+  color: #ccd6f6;
+}
+
+.file-card .file-type {
+  font-size: 0.8rem;
+  color: #8892b0;
+  margin-bottom: 0.75rem;
+}
+
+.file-card .file-actions {
+  display: flex;
+  gap: 0.5rem;
+}
+
+.file-card .file-actions a {
+  padding: 0.4rem 0.8rem;
+  background: rgba(233, 69, 96, 0.2);
+  color: #e94560;
+  text-decoration: none;
+  border-radius: 4px;
+  font-size: 0.85rem;
+  transition: all 0.3s ease;
+}
+
+.file-card .file-actions a:hover {
+  background: #e94560;
+  color: #fff;
+}
+
+/* Loading spinner */
+@keyframes spin {
+  to { transform: rotate(360deg); }
+}
+
+.spinner {
+  display: inline-block;
+  width: 16px;
+  height: 16px;
+  border: 2px solid rgba(255, 255, 255, 0.3);
+  border-top-color: #fff;
+  border-radius: 50%;
+  animation: spin 0.8s linear infinite;
+  margin-right: 0.5rem;
+}
+
+/* Status indicator */
+.status {
+  display: inline-block;
+  padding: 0.25rem 0.5rem;
+  border-radius: 4px;
+  font-size: 0.8rem;
+  margin-left: 0.5rem;
+}
+
+.status.downloading {
+  background: rgba(59, 130, 246, 0.2);
+  color: #3b82f6;
+}
+
+.status.transcribing {
+  background: rgba(168, 85, 247, 0.2);
+  color: #a855f7;
+}
+
+.status.complete {
+  background: rgba(16, 185, 129, 0.2);
+  color: #10b981;
+}
+
+/* Empty state */
+.empty-state {
+  text-align: center;
+  padding: 3rem;
+  color: #8892b0;
+}
+
+.empty-state p {
+  margin-top: 1rem;
+}
+
+/* Progress Bar */
+.progress-container {
+  margin-top: 1.5rem;
+  padding: 1.5rem;
+  background: rgba(255, 255, 255, 0.05);
+  border-radius: 12px;
+  border: 1px solid #233554;
+}
+
+.progress-header {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  margin-bottom: 1rem;
+}
+
+.progress-header #progress-title {
+  font-weight: 600;
+  color: #ccd6f6;
+  font-size: 1rem;
+}
+
+.progress-header #progress-eta {
+  color: #e94560;
+  font-size: 0.9rem;
+  font-weight: 500;
+}
+
+.progress-bar {
+  width: 100%;
+  height: 12px;
+  background: rgba(255, 255, 255, 0.1);
+  border-radius: 6px;
+  overflow: hidden;
+  position: relative;
+}
+
+.progress-fill {
+  height: 100%;
+  background: linear-gradient(90deg, #e94560, #ff6b8a);
+  border-radius: 6px;
+  width: 0%;
+  transition: width 0.3s ease;
+  position: relative;
+}
+
+.progress-fill::after {
+  content: '';
+  position: absolute;
+  top: 0;
+  left: 0;
+  right: 0;
+  bottom: 0;
+  background: linear-gradient(
+    90deg,
+    transparent,
+    rgba(255, 255, 255, 0.3),
+    transparent
+  );
+  animation: shimmer 2s infinite;
+}
+
+@keyframes shimmer {
+  0% { transform: translateX(-100%); }
+  100% { transform: translateX(100%); }
+}
+
+.progress-details {
+  display: flex;
+  justify-content: space-between;
+  margin-top: 0.75rem;
+  font-size: 0.85rem;
+  color: #8892b0;
+}
+
+.progress-details #progress-percent {
+  color: #ccd6f6;
+  font-weight: 600;
+}
+
+.progress-details #progress-speed {
+  color: #10b981;
+}
+
+.progress-current {
+  margin-top: 1rem;
+  padding-top: 1rem;
+  border-top: 1px solid rgba(255, 255, 255, 0.1);
+  font-size: 0.9rem;
+  color: #8892b0;
+}
+
+.progress-current .video-title {
+  color: #ccd6f6;
+  font-weight: 500;
+}
+
+/* Drag and Drop Zone */
+.drop-zone {
+  border: 2px dashed #233554;
+  border-radius: 12px;
+  padding: 3rem 2rem;
+  text-align: center;
+  cursor: pointer;
+  transition: all 0.3s ease;
+  margin-bottom: 1.5rem;
+  background: rgba(255, 255, 255, 0.02);
+}
+
+.drop-zone:hover {
+  border-color: #e94560;
+  background: rgba(233, 69, 96, 0.05);
+}
+
+.drop-zone.drag-over {
+  border-color: #e94560;
+  background: rgba(233, 69, 96, 0.1);
+  transform: scale(1.02);
+}
+
+.drop-zone-icon {
+  color: #8892b0;
+  margin-bottom: 1rem;
+  transition: color 0.3s ease;
+}
+
+.drop-zone:hover .drop-zone-icon {
+  color: #e94560;
+}
+
+.drop-zone-text {
+  color: #ccd6f6;
+  font-size: 1.1rem;
+  margin-bottom: 0.5rem;
+}
+
+.drop-zone-hint {
+  color: #8892b0;
+  font-size: 0.9rem;
+}
+
+.drop-zone-formats {
+  color: #64748b;
+  font-size: 0.75rem;
+  margin-top: 0.5rem;
+  font-style: italic;
+}
+
+/* Selected Files List */
+.selected-files {
+  background: rgba(255, 255, 255, 0.05);
+  border-radius: 8px;
+  padding: 1rem;
+  margin-bottom: 1.5rem;
+}
+
+.selected-files h3 {
+  font-size: 0.9rem;
+  color: #8892b0;
+  margin-bottom: 0.75rem;
+  text-transform: uppercase;
+  letter-spacing: 0.5px;
+}
+
+.selected-files ul {
+  list-style: none;
+  margin-bottom: 1rem;
+}
+
+.selected-files li {
+  display: flex;
+  align-items: center;
+  justify-content: space-between;
+  padding: 0.5rem 0;
+  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
+  color: #ccd6f6;
+}
+
+.selected-files li:last-child {
+  border-bottom: none;
+}
+
+.selected-files .file-name {
+  flex: 1;
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
+.selected-files .file-size {
+  color: #8892b0;
+  font-size: 0.85rem;
+  margin-left: 1rem;
+}
+
+.selected-files .remove-file {
+  background: none;
+  border: none;
+  color: #ef4444;
+  cursor: pointer;
+  padding: 0.25rem;
+  margin-left: 0.5rem;
+  font-size: 1.2rem;
+  line-height: 1;
+}
+
+.selected-files .remove-file:hover {
+  color: #ff6b6b;
+}
+
+/* Checkbox Group */
+.checkbox-group {
+  margin-bottom: 1rem;
+}
+
+.checkbox-label {
+  display: flex;
+  align-items: center;
+  gap: 0.5rem;
+  cursor: pointer;
+  color: #ccd6f6;
+  font-size: 0.95rem;
+}
+
+.checkbox-label input[type="checkbox"] {
+  width: 18px;
+  height: 18px;
+  accent-color: #e94560;
+  cursor: pointer;
+}
+
+.translate-lang-select {
+  margin-top: 0.75rem;
+  width: auto;
+  min-width: 150px;
+}
+
+.translate-lang-select:disabled {
+  opacity: 0.5;
+  cursor: not-allowed;
+}
+
+/* Translate Tab */
+.translate-mode-selector {
+  display: flex;
+  gap: 0.5rem;
+  margin-bottom: 1.5rem;
+}
+
+.mode-btn {
+  padding: 0.6rem 1.25rem;
+  background: rgba(255, 255, 255, 0.05);
+  border: 1px solid #233554;
+  color: #8892b0;
+  border-radius: 8px;
+  cursor: pointer;
+  font-size: 0.95rem;
+  transition: all 0.3s ease;
+}
+
+.mode-btn:hover {
+  border-color: #e94560;
+  color: #ccd6f6;
+}
+
+.mode-btn.active {
+  background: rgba(233, 69, 96, 0.2);
+  border-color: #e94560;
+  color: #e94560;
+}
+
+.translate-mode {
+  animation: fadeIn 0.3s ease;
+}
+
+/* Textarea */
+textarea {
+  width: 100%;
+  padding: 1rem;
+  background: rgba(255, 255, 255, 0.1);
+  border: 1px solid #233554;
+  border-radius: 8px;
+  color: #fff;
+  font-size: 1rem;
+  font-family: inherit;
+  resize: vertical;
+  min-height: 150px;
+  transition: all 0.3s ease;
+}
+
+textarea:focus {
+  outline: none;
+  border-color: #e94560;
+  background: rgba(233, 69, 96, 0.1);
+}
+
+textarea::placeholder {
+  color: #8892b0;
+}
+
+/* Translation Result */
+.translation-output {
+  margin-top: 1rem;
+  padding: 1rem;
+  background: rgba(0, 0, 0, 0.3);
+  border-radius: 8px;
+  white-space: pre-wrap;
+  max-height: 400px;
+  overflow-y: auto;
+  color: #ccd6f6;
+  line-height: 1.6;
+}
+
+/* Summarize Tab */
+.summarize-mode-selector {
+  display: flex;
+  gap: 0.5rem;
+  margin-bottom: 1.5rem;
+}
+
+.summarize-mode {
+  animation: fadeIn 0.3s ease;
+}
+
+/* Summary Result */
+.summary-output {
+  margin-top: 1rem;
+  padding: 1rem;
+  background: rgba(0, 0, 0, 0.3);
+  border-radius: 8px;
+  white-space: pre-wrap;
+  max-height: 400px;
+  overflow-y: auto;
+  color: #ccd6f6;
+  line-height: 1.6;
+}
diff --git a/src/server.js b/src/server.js
index f16ed6d..ec7bf67 100644
--- a/src/server.js
+++ b/src/server.js
@@ -1,1137 +1,1137 @@
-import express from 'express';
-import cors from 'cors';
-import dotenv from 'dotenv';
-import path from 'path';
-import fs from 'fs';
-import { fileURLToPath } from 'url';
-import multer from 'multer';
-import { download, getInfo } from './services/youtube.js';
-import { transcribeFile, transcribeAndSave, transcribeMultiple } from './services/transcription.js';
-import { translateText, translateFile, translateMultiple, getLanguages } from './services/translation.js';
-import { summarizeText, summarizeFile, getSummaryStyles } from './services/summarize.js';
-import { convertToMP3, convertMultipleToMP3, getSupportedFormats } from './services/conversion.js';
-
-dotenv.config();
-
-const app = express();
-const PORT = process.env.PORT || 8888;
-const OUTPUT_DIR = process.env.OUTPUT_DIR || './output';
-
-// Ensure output directory exists
-if (!fs.existsSync(OUTPUT_DIR)) {
-  fs.mkdirSync(OUTPUT_DIR, { recursive: true });
-}
-
-// Configure multer for file uploads
-const storage = multer.diskStorage({
-  destination: (req, file, cb) => {
-    cb(null, OUTPUT_DIR);
-  },
-  filename: (req, file, cb) => {
-    // Keep original filename but sanitize it
-    const safeName = file.originalname.replace(/[^a-zA-Z0-9._-]/g, '_');
-    cb(null, safeName);
-  }
-});
-
-const upload = multer({
-  storage,
-  fileFilter: (req, file, cb) => {
-    const allowedTypes = ['audio/mpeg', 'audio/mp3', 'audio/wav', 'audio/m4a', 'audio/ogg', 'audio/flac', 'audio/x-m4a'];
-    if (allowedTypes.includes(file.mimetype) || file.originalname.match(/\.(mp3|wav|m4a|ogg|flac)$/i)) {
-      cb(null, true);
-    } else {
-      cb(new Error('Invalid file type. Only audio files are allowed.'));
-    }
-  }
-});
-
-// Upload handler for text files (for translation)
-const uploadText = multer({
-  storage,
-  fileFilter: (req, file, cb) => {
-    if (file.mimetype === 'text/plain' || file.originalname.endsWith('.txt')) {
-      cb(null, true);
-    } else {
-      cb(new Error('Invalid file type. Only text files (.txt) are allowed.'));
-    }
-  }
-});
-
-// Upload handler for video/audio files (for conversion)
-const uploadVideo = multer({
-  storage,
-  fileFilter: (req, file, cb) => {
-    const videoTypes = ['video/mp4', 'video/avi', 'video/x-msvideo', 'video/quicktime', 'video/x-matroska', 'video/webm'];
-    const audioTypes = ['audio/m4a', 'audio/x-m4a', 'audio/wav', 'audio/flac', 'audio/ogg', 'audio/aac'];
-    const videoExtensions = /\.(mp4|avi|mkv|mov|wmv|flv|webm|m4v|m4a|wav|flac|ogg|aac)$/i;
-
-    if (videoTypes.includes(file.mimetype) || audioTypes.includes(file.mimetype) || file.originalname.match(videoExtensions)) {
-      cb(null, true);
-    } else {
-      cb(new Error('Invalid file type. Only video/audio files are allowed.'));
-    }
-  }
-});
-
-app.use(cors());
-app.use(express.json());
-
-// Set permissive CSP for development
-app.use((req, res, next) => {
-  res.setHeader(
-    'Content-Security-Policy',
-    "default-src 'self'; script-src 'self' 'unsafe-inline'; style-src 'self' 'unsafe-inline'; img-src 'self' data:; connect-src 'self'"
-  );
-  next();
-});
-
-// Serve static files (HTML interface)
-const __filename = fileURLToPath(import.meta.url);
-const __dirname = path.dirname(__filename);
-app.use(express.static(path.join(__dirname, '../public')));
-
-// Serve downloaded files
-app.use('/files', express.static(OUTPUT_DIR));
-
-// API info endpoint
-app.get('/api', (req, res) => {
-  res.json({
-    name: 'Video to MP3 Transcriptor API',
-    version: '1.0.0',
-    endpoints: {
-      'GET /health': 'Health check',
-      'GET /info?url=': 'Get video/playlist info',
-      'POST /download': 'Download as MP3',
-      'POST /transcribe': 'Transcribe audio file',
-      'POST /process': 'Download + transcribe',
-      'GET /files-list': 'List downloaded files',
-      'GET /files/<name>': 'Serve downloaded files',
-    },
-  });
-});
-
-// Health check
-app.get('/health', (req, res) => {
-  res.json({ status: 'ok', timestamp: new Date().toISOString() });
-});
-
-/**
- * GET /info?url=<youtube_url>
- * Get info about a video or playlist
- */
-app.get('/info', async (req, res) => {
-  try {
-    const { url } = req.query;
-
-    if (!url) {
-      return res.status(400).json({ error: 'URL parameter required' });
-    }
-
-    // Check if URL contains playlist parameter
-    const hasPlaylist = url.includes('list=');
-    const info = await getInfo(url, hasPlaylist);
-
-    res.json({
-      success: true,
-      title: info.title,
-      type: info._type || 'video',
-      duration: info.duration,
-      channel: info.channel,
-      entries: info._type === 'playlist'
-        ? info.entries?.map(e => ({ id: e.id, title: e.title }))
-        : null,
-      videoCount: info._type === 'playlist' ? info.entries?.length : 1,
-    });
-  } catch (error) {
-    res.status(500).json({ error: error.message });
-  }
-});
-
-/**
- * GET /download-stream
- * Download with SSE progress updates
- * Query: url (required), outputPath (optional)
- */
-app.get('/download-stream', async (req, res) => {
-  const { url, outputPath } = req.query;
-
-  if (!url) {
-    return res.status(400).json({ error: 'URL parameter required' });
-  }
-
-  // Set up SSE
-  res.setHeader('Content-Type', 'text/event-stream');
-  res.setHeader('Cache-Control', 'no-cache');
-  res.setHeader('Connection', 'keep-alive');
-  res.setHeader('Access-Control-Allow-Origin', '*');
-
-  const sendEvent = (event, data) => {
-    res.write(`event: ${event}\ndata: ${JSON.stringify(data)}\n\n`);
-  };
-
-  // Track timing for estimation
-  const startTime = Date.now();
-  let videosCompleted = 0;
-  let totalVideos = 1;
-  const videoTimes = [];
-
-  try {
-    // First, get info to know total videos
-    sendEvent('status', { message: 'Fetching video info...', phase: 'info' });
-    const hasPlaylist = url.includes('list=');
-    const info = await getInfo(url, hasPlaylist);
-
-    totalVideos = info._type === 'playlist' ? (info.entries?.length || 1) : 1;
-    sendEvent('info', {
-      title: info.title,
-      type: info._type || 'video',
-      totalVideos,
-      playlistTitle: info._type === 'playlist' ? info.title : null,
-    });
-
-    console.log(`Downloading: ${url}`);
-
-    let videoStartTime = Date.now();
-
-    const result = await download(url, {
-      outputDir: outputPath || OUTPUT_DIR,
-      onDownloadProgress: (progress) => {
-        // Calculate overall progress
-        const videoProgress = progress.percent || 0;
-        const overallPercent = ((videosCompleted + (videoProgress / 100)) / totalVideos) * 100;
-
-        // Estimate remaining time
-        let estimatedRemaining = null;
-        if (videosCompleted > 0 && videoTimes.length > 0) {
-          const avgTimePerVideo = videoTimes.reduce((a, b) => a + b, 0) / videoTimes.length;
-          const remainingVideos = totalVideos - videosCompleted - (videoProgress / 100);
-          estimatedRemaining = Math.round(avgTimePerVideo * remainingVideos / 1000);
-        } else if (progress.eta) {
-          // Parse ETA from yt-dlp (format: MM:SS)
-          const [mins, secs] = progress.eta.split(':').map(Number);
-          const currentVideoRemaining = mins * 60 + secs;
-          const remainingVideos = totalVideos - videosCompleted - 1;
-          // Estimate based on current video
-          if (videoProgress > 10) {
-            const elapsed = (Date.now() - videoStartTime) / 1000;
-            const estimatedVideoTime = (elapsed / videoProgress) * 100;
-            estimatedRemaining = Math.round(currentVideoRemaining + (remainingVideos * estimatedVideoTime));
-          }
-        }
-
-        sendEvent('progress', {
-          percent: Math.round(overallPercent * 10) / 10,
-          videoPercent: Math.round(videoProgress * 10) / 10,
-          currentVideo: progress.videoIndex || 1,
-          totalVideos: progress.totalVideos || totalVideos,
-          title: progress.title,
-          speed: progress.speed,
-          eta: progress.eta,
-          estimatedRemaining,
-          phase: 'downloading',
-        });
-      },
-      onVideoComplete: (video) => {
-        const videoTime = Date.now() - videoStartTime;
-        videoTimes.push(videoTime);
-        videosCompleted++;
-        videoStartTime = Date.now();
-
-        sendEvent('video-complete', {
-          title: video.title,
-          success: video.success,
-          videosCompleted,
-          totalVideos,
-        });
-      },
-    });
-
-    // Send final result
-    sendEvent('complete', {
-      success: true,
-      playlistTitle: result.playlistTitle,
-      totalVideos: result.totalVideos,
-      successCount: result.successCount,
-      failCount: result.failCount,
-      totalTime: Math.round((Date.now() - startTime) / 1000),
-      videos: result.videos.map(v => ({
-        success: v.success,
-        title: v.title,
-        filePath: v.filePath,
-        fileUrl: v.filePath ? `/files/${path.basename(v.filePath)}` : null,
-        error: v.error,
-      })),
-    });
-
-  } catch (error) {
-    sendEvent('error', { message: error.message });
-  } finally {
-    res.end();
-  }
-});
-
-/**
- * POST /download
- * Download a video or playlist as MP3 (non-streaming version)
- * Body: { url: string, outputPath?: string }
- */
-app.post('/download', async (req, res) => {
-  try {
-    const { url, outputPath } = req.body;
-    const outputDir = outputPath || OUTPUT_DIR;
-
-    if (!url) {
-      return res.status(400).json({ error: 'URL required in request body' });
-    }
-
-    console.log(`Downloading: ${url}`);
-    const result = await download(url, { outputDir });
-
-    res.json({
-      success: true,
-      playlistTitle: result.playlistTitle,
-      totalVideos: result.totalVideos,
-      successCount: result.successCount,
-      failCount: result.failCount,
-      videos: result.videos.map(v => ({
-        success: v.success,
-        title: v.title,
-        filePath: v.filePath,
-        fileUrl: v.filePath ? `/files/${path.basename(v.filePath)}` : null,
-        error: v.error,
-      })),
-    });
-  } catch (error) {
-    res.status(500).json({ error: error.message });
-  }
-});
-
-/**
- * POST /transcribe
- * Transcribe an existing audio file
- * Body: { filePath: string, language?: string, format?: string, outputPath?: string }
- */
-app.post('/transcribe', async (req, res) => {
-  try {
-    const { filePath, language, format = 'txt', model = 'gpt-4o-mini-transcribe', outputPath } = req.body;
-
-    if (!filePath) {
-      return res.status(400).json({ error: 'filePath required in request body' });
-    }
-
-    if (!process.env.OPENAI_API_KEY) {
-      return res.status(500).json({ error: 'OPENAI_API_KEY not configured' });
-    }
-
-    console.log(`Transcribing: ${filePath} with model ${model}`);
-    const result = await transcribeAndSave(filePath, {
-      language,
-      responseFormat: format === 'txt' ? 'text' : format,
-      outputFormat: format,
-      model,
-      outputDir: outputPath,
-    });
-
-    res.json({
-      success: true,
-      filePath: result.filePath,
-      transcriptionPath: result.transcriptionPath,
-      transcriptionUrl: `/files/${path.basename(result.transcriptionPath)}`,
-      text: result.text,
-    });
-  } catch (error) {
-    res.status(500).json({ error: error.message });
-  }
-});
-
-/**
- * POST /upload-transcribe
- * Upload audio files and transcribe them
- * Body: { language?: string, model?: string, outputPath?: string }
- */
-app.post('/upload-transcribe', upload.array('files', 50), async (req, res) => {
-  try {
-    if (!process.env.OPENAI_API_KEY) {
-      return res.status(500).json({ error: 'OPENAI_API_KEY not configured' });
-    }
-
-    if (!req.files || req.files.length === 0) {
-      return res.status(400).json({ error: 'No files uploaded' });
-    }
-
-    const { language, model = 'gpt-4o-mini-transcribe', outputPath } = req.body;
-    const results = [];
-
-    console.log(`Transcribing ${req.files.length} uploaded files with model ${model}`);
-
-    for (let i = 0; i < req.files.length; i++) {
-      const file = req.files[i];
-      console.log(`[${i + 1}/${req.files.length}] Transcribing: ${file.originalname}`);
-
-      try {
-        const result = await transcribeAndSave(file.path, {
-          language: language || undefined,
-          responseFormat: 'text',
-          outputFormat: 'txt',
-          model,
-          outputDir: outputPath,
-        });
-
-        results.push({
-          success: true,
-          fileName: file.originalname,
-          filePath: file.path,
-          transcriptionPath: result.transcriptionPath,
-          transcriptionUrl: `/files/${path.basename(result.transcriptionPath)}`,
-          text: result.text,
-        });
-      } catch (error) {
-        console.error(`Failed to transcribe ${file.originalname}: ${error.message}`);
-        results.push({
-          success: false,
-          fileName: file.originalname,
-          error: error.message,
-        });
-      }
-    }
-
-    res.json({
-      success: true,
-      totalFiles: req.files.length,
-      successCount: results.filter(r => r.success).length,
-      failCount: results.filter(r => !r.success).length,
-      results,
-    });
-  } catch (error) {
-    res.status(500).json({ error: error.message });
-  }
-});
-
-/**
- * POST /convert-to-mp3
- * Upload video/audio files and convert them to MP3
- */
-app.post('/convert-to-mp3', uploadVideo.array('files', 50), async (req, res) => {
-  try {
-    if (!req.files || req.files.length === 0) {
-      return res.status(400).json({ error: 'No files uploaded' });
-    }
-
-    const { bitrate = '192k', quality = '2' } = req.body;
-    const results = [];
-
-    console.log(`Converting ${req.files.length} files to MP3`);
-
-    for (let i = 0; i < req.files.length; i++) {
-      const file = req.files[i];
-      console.log(`[${i + 1}/${req.files.length}] Converting: ${file.originalname}`);
-
-      try {
-        const result = await convertToMP3(file.path, {
-          outputDir: OUTPUT_DIR,
-          bitrate,
-          quality,
-        });
-
-        results.push({
-          success: true,
-          fileName: file.originalname,
-          inputPath: file.path,
-          outputPath: result.outputPath,
-          outputUrl: `/files/${path.basename(result.outputPath)}`,
-          size: result.sizeHuman,
-        });
-      } catch (error) {
-        console.error(`Failed to convert ${file.originalname}: ${error.message}`);
-        results.push({
-          success: false,
-          fileName: file.originalname,
-          error: error.message,
-        });
-      }
-    }
-
-    res.json({
-      success: true,
-      totalFiles: req.files.length,
-      successCount: results.filter(r => r.success).length,
-      failCount: results.filter(r => !r.success).length,
-      results,
-    });
-  } catch (error) {
-    res.status(500).json({ error: error.message });
-  }
-});
-
-/**
- * GET /supported-formats
- * Get supported video/audio formats for conversion
- */
-app.get('/supported-formats', (req, res) => {
-  res.json({ formats: getSupportedFormats() });
-});
-
-/**
- * GET /process-stream
- * Download and transcribe with SSE progress updates
- * Query: url, language?, model?, outputPath?
- */
-app.get('/process-stream', async (req, res) => {
-  const { url, language, model = 'gpt-4o-mini-transcribe', outputPath } = req.query;
-
-  if (!url) {
-    return res.status(400).json({ error: 'URL parameter required' });
-  }
-
-  if (!process.env.OPENAI_API_KEY) {
-    return res.status(500).json({ error: 'OPENAI_API_KEY not configured' });
-  }
-
-  // Set up SSE
-  res.setHeader('Content-Type', 'text/event-stream');
-  res.setHeader('Cache-Control', 'no-cache');
-  res.setHeader('Connection', 'keep-alive');
-  res.setHeader('Access-Control-Allow-Origin', '*');
-
-  const sendEvent = (event, data) => {
-    res.write(`event: ${event}\ndata: ${JSON.stringify(data)}\n\n`);
-  };
-
-  const startTime = Date.now();
-  let videosDownloaded = 0;
-  let videosTranscribed = 0;
-  let totalVideos = 1;
-  const videoTimes = [];
-
-  try {
-    // Phase 1: Get info
-    sendEvent('status', { message: 'Fetching video info...', phase: 'info' });
-    const hasPlaylist = url.includes('list=');
-    const info = await getInfo(url, hasPlaylist);
-
-    totalVideos = info._type === 'playlist' ? (info.entries?.length || 1) : 1;
-    sendEvent('info', {
-      title: info.title,
-      type: info._type || 'video',
-      totalVideos,
-      playlistTitle: info._type === 'playlist' ? info.title : null,
-    });
-
-    // Phase 2: Download
-    console.log(`Processing: ${url}`);
-    let videoStartTime = Date.now();
-
-    const downloadResult = await download(url, {
-      outputDir: outputPath || OUTPUT_DIR,
-      onDownloadProgress: (progress) => {
-        const videoProgress = progress.percent || 0;
-        // Download is 50% of total, transcribe is other 50%
-        const overallPercent = ((videosDownloaded + (videoProgress / 100)) / totalVideos) * 50;
-
-        sendEvent('progress', {
-          percent: Math.round(overallPercent * 10) / 10,
-          videoPercent: Math.round(videoProgress * 10) / 10,
-          currentVideo: progress.videoIndex || 1,
-          totalVideos: progress.totalVideos || totalVideos,
-          title: progress.title,
-          speed: progress.speed,
-          eta: progress.eta,
-          phase: 'downloading',
-          phaseLabel: 'Downloading',
-        });
-      },
-      onVideoComplete: (video) => {
-        const videoTime = Date.now() - videoStartTime;
-        videoTimes.push(videoTime);
-        videosDownloaded++;
-        videoStartTime = Date.now();
-
-        sendEvent('video-complete', {
-          title: video.title,
-          success: video.success,
-          phase: 'downloading',
-          videosCompleted: videosDownloaded,
-          totalVideos,
-        });
-      },
-    });
-
-    // Phase 3: Transcribe
-    sendEvent('status', { message: 'Starting transcription...', phase: 'transcribing' });
-
-    const successfulDownloads = downloadResult.videos.filter(v => v.success);
-    const filePaths = successfulDownloads.map(v => v.filePath);
-    const transcribeResults = [];
-
-    for (let i = 0; i < filePaths.length; i++) {
-      const filePath = filePaths[i];
-      const video = successfulDownloads[i];
-
-      sendEvent('progress', {
-        percent: 50 + ((i / filePaths.length) * 50),
-        currentVideo: i + 1,
-        totalVideos: filePaths.length,
-        title: video.title,
-        phase: 'transcribing',
-        phaseLabel: 'Transcribing',
-      });
-
-      try {
-        const result = await transcribeAndSave(filePath, {
-          language: language || undefined,
-          responseFormat: 'text',
-          outputFormat: 'txt',
-          model,
-          outputDir: outputPath,
-        });
-        transcribeResults.push(result);
-        videosTranscribed++;
-
-        sendEvent('transcribe-complete', {
-          title: video.title,
-          success: true,
-          videosCompleted: videosTranscribed,
-          totalFiles: filePaths.length,
-        });
-      } catch (error) {
-        transcribeResults.push({
-          success: false,
-          filePath,
-          error: error.message,
-        });
-
-        sendEvent('transcribe-complete', {
-          title: video.title,
-          success: false,
-          error: error.message,
-          videosCompleted: videosTranscribed,
-          totalFiles: filePaths.length,
-        });
-      }
-    }
-
-    // Combine results
-    const combinedResults = downloadResult.videos.map(v => {
-      const transcription = transcribeResults.find(t => t.filePath === v.filePath);
-      return {
-        title: v.title,
-        downloadSuccess: v.success,
-        audioUrl: v.filePath ? `/files/${path.basename(v.filePath)}` : null,
-        transcriptionSuccess: transcription?.success || false,
-        transcriptionUrl: transcription?.transcriptionPath
-          ? `/files/${path.basename(transcription.transcriptionPath)}`
-          : null,
-        text: transcription?.text,
-        error: v.error || transcription?.error,
-      };
-    });
-
-    sendEvent('complete', {
-      success: true,
-      playlistTitle: downloadResult.playlistTitle,
-      totalVideos: downloadResult.totalVideos,
-      downloadedCount: downloadResult.successCount,
-      transcribedCount: videosTranscribed,
-      totalTime: Math.round((Date.now() - startTime) / 1000),
-      results: combinedResults,
-    });
-
-  } catch (error) {
-    sendEvent('error', { message: error.message });
-  } finally {
-    res.end();
-  }
-});
-
-/**
- * POST /process
- * Download and transcribe a video or playlist (non-streaming)
- * Body: { url: string, language?: string, format?: string, outputPath?: string }
- */
-app.post('/process', async (req, res) => {
-  try {
-    const { url, language, format = 'txt', outputPath, model = 'gpt-4o-mini-transcribe' } = req.body;
-    const outputDir = outputPath || OUTPUT_DIR;
-
-    if (!url) {
-      return res.status(400).json({ error: 'URL required in request body' });
-    }
-
-    if (!process.env.OPENAI_API_KEY) {
-      return res.status(500).json({ error: 'OPENAI_API_KEY not configured' });
-    }
-
-    // Step 1: Download
-    console.log(`Step 1: Downloading ${url}`);
-    const downloadResult = await download(url, { outputDir });
-
-    // Step 2: Transcribe
-    console.log(`Step 2: Transcribing with model ${model}...`);
-    const successfulDownloads = downloadResult.videos.filter(v => v.success);
-    const filePaths = successfulDownloads.map(v => v.filePath);
-
-    const transcribeResult = await transcribeMultiple(filePaths, {
-      language,
-      responseFormat: format === 'txt' ? 'text' : format,
-      outputFormat: format,
-      model,
-      outputDir,
-    });
-
-    // Combine results
-    const combinedResults = downloadResult.videos.map(v => {
-      const transcription = transcribeResult.results.find(
-        t => t.filePath === v.filePath
-      );
-
-      return {
-        title: v.title,
-        downloadSuccess: v.success,
-        audioPath: v.filePath,
-        audioUrl: v.filePath ? `/files/${path.basename(v.filePath)}` : null,
-        transcriptionSuccess: transcription?.success || false,
-        transcriptionPath: transcription?.transcriptionPath,
-        transcriptionUrl: transcription?.transcriptionPath
-          ? `/files/${path.basename(transcription.transcriptionPath)}`
-          : null,
-        text: transcription?.text,
-        error: v.error || transcription?.error,
-      };
-    });
-
-    res.json({
-      success: true,
-      playlistTitle: downloadResult.playlistTitle,
-      totalVideos: downloadResult.totalVideos,
-      downloadedCount: downloadResult.successCount,
-      transcribedCount: transcribeResult.successCount,
-      results: combinedResults,
-    });
-  } catch (error) {
-    res.status(500).json({ error: error.message });
-  }
-});
-
-/**
- * GET /files
- * List all downloaded files
- */
-app.get('/files-list', (req, res) => {
-  try {
-    if (!fs.existsSync(OUTPUT_DIR)) {
-      return res.json({ files: [] });
-    }
-
-    const files = fs.readdirSync(OUTPUT_DIR).map(file => ({
-      name: file,
-      url: `/files/${file}`,
-      path: path.join(OUTPUT_DIR, file),
-    }));
-
-    res.json({ files });
-  } catch (error) {
-    res.status(500).json({ error: error.message });
-  }
-});
-
-/**
- * GET /languages
- * Get available translation languages
- */
-app.get('/languages', (req, res) => {
-  res.json({ languages: getLanguages() });
-});
-
-/**
- * POST /translate
- * Translate text
- * Body: { text: string, targetLang: string, sourceLang?: string }
- */
-app.post('/translate', async (req, res) => {
-  try {
-    const { text, targetLang, sourceLang } = req.body;
-
-    if (!text) {
-      return res.status(400).json({ error: 'text required in request body' });
-    }
-    if (!targetLang) {
-      return res.status(400).json({ error: 'targetLang required in request body' });
-    }
-
-    if (!process.env.OPENAI_API_KEY) {
-      return res.status(500).json({ error: 'OPENAI_API_KEY not configured' });
-    }
-
-    console.log(`Translating text to ${targetLang}`);
-    const result = await translateText(text, targetLang, sourceLang);
-
-    res.json({
-      success: true,
-      ...result,
-    });
-  } catch (error) {
-    res.status(500).json({ error: error.message });
-  }
-});
-
-/**
- * POST /translate-file
- * Translate uploaded text files
- * Body: { targetLang: string, sourceLang?: string, outputPath?: string }
- */
-app.post('/translate-file', uploadText.array('files', 50), async (req, res) => {
-  try {
-    if (!process.env.OPENAI_API_KEY) {
-      return res.status(500).json({ error: 'OPENAI_API_KEY not configured' });
-    }
-
-    if (!req.files || req.files.length === 0) {
-      return res.status(400).json({ error: 'No files uploaded' });
-    }
-
-    const { targetLang, sourceLang, outputPath } = req.body;
-
-    if (!targetLang) {
-      return res.status(400).json({ error: 'targetLang required' });
-    }
-
-    const results = [];
-    console.log(`Translating ${req.files.length} files to ${targetLang}`);
-
-    for (let i = 0; i < req.files.length; i++) {
-      const file = req.files[i];
-      console.log(`[${i + 1}/${req.files.length}] Translating: ${file.originalname}`);
-
-      try {
-        const result = await translateFile(file.path, targetLang, sourceLang || null, outputPath);
-        results.push({
-          success: true,
-          fileName: file.originalname,
-          translationPath: result.translationPath,
-          translationUrl: `/files/${path.basename(result.translationPath)}`,
-          translatedText: result.translatedText,
-        });
-      } catch (error) {
-        console.error(`Failed to translate ${file.originalname}: ${error.message}`);
-        results.push({
-          success: false,
-          fileName: file.originalname,
-          error: error.message,
-        });
-      }
-    }
-
-    res.json({
-      success: true,
-      totalFiles: req.files.length,
-      successCount: results.filter(r => r.success).length,
-      failCount: results.filter(r => !r.success).length,
-      results,
-    });
-  } catch (error) {
-    res.status(500).json({ error: error.message });
-  }
-});
-
-/**
- * GET /summary-styles
- * Get available summary styles
- */
-app.get('/summary-styles', (req, res) => {
-  res.json({ styles: getSummaryStyles() });
-});
-
-/**
- * POST /summarize
- * Summarize text using GPT-5.1
- * Body: { text: string, style?: string, language?: string, model?: string }
- */
-app.post('/summarize', async (req, res) => {
-  try {
-    const { text, style = 'concise', language = 'same', model = 'gpt-5.1' } = req.body;
-
-    if (!text) {
-      return res.status(400).json({ error: 'text required in request body' });
-    }
-
-    if (!process.env.OPENAI_API_KEY) {
-      return res.status(500).json({ error: 'OPENAI_API_KEY not configured' });
-    }
-
-    console.log(`Summarizing text with ${model} (style: ${style})`);
-    const result = await summarizeText(text, { style, language, model });
-
-    res.json({
-      success: true,
-      ...result,
-    });
-  } catch (error) {
-    res.status(500).json({ error: error.message });
-  }
-});
-
-/**
- * POST /summarize-file
- * Summarize uploaded text files using GPT-5.1
- * Body: { style?: string, language?: string, model?: string, outputPath?: string }
- */
-app.post('/summarize-file', uploadText.array('files', 50), async (req, res) => {
-  try {
-    if (!process.env.OPENAI_API_KEY) {
-      return res.status(500).json({ error: 'OPENAI_API_KEY not configured' });
-    }
-
-    if (!req.files || req.files.length === 0) {
-      return res.status(400).json({ error: 'No files uploaded' });
-    }
-
-    const { style = 'concise', language = 'same', model = 'gpt-5.1', outputPath } = req.body;
-    const results = [];
-
-    console.log(`Summarizing ${req.files.length} files with ${model}`);
-
-    for (let i = 0; i < req.files.length; i++) {
-      const file = req.files[i];
-      console.log(`[${i + 1}/${req.files.length}] Summarizing: ${file.originalname}`);
-
-      try {
-        const result = await summarizeFile(file.path, { style, language, model, outputDir: outputPath });
-        results.push({
-          success: true,
-          fileName: file.originalname,
-          summaryPath: result.summaryPath,
-          summaryUrl: `/files/${path.basename(result.summaryPath)}`,
-          summary: result.summary,
-          model: result.model,
-          chunks: result.chunks,
-        });
-      } catch (error) {
-        console.error(`Failed to summarize ${file.originalname}: ${error.message}`);
-        results.push({
-          success: false,
-          fileName: file.originalname,
-          error: error.message,
-        });
-      }
-    }
-
-    res.json({
-      success: true,
-      totalFiles: req.files.length,
-      successCount: results.filter(r => r.success).length,
-      failCount: results.filter(r => !r.success).length,
-      results,
-    });
-  } catch (error) {
-    res.status(500).json({ error: error.message });
-  }
-});
-
-/**
- * GET /summarize-stream
- * Full pipeline: Download -> Transcribe -> Summarize with SSE progress
- * Query: url, style?, language?, model?, outputPath?
- */
-app.get('/summarize-stream', async (req, res) => {
-  const { url, style = 'concise', language = 'same', model = 'gpt-4o-mini-transcribe', outputPath } = req.query;
-
-  if (!url) {
-    return res.status(400).json({ error: 'URL parameter required' });
-  }
-
-  if (!process.env.OPENAI_API_KEY) {
-    return res.status(500).json({ error: 'OPENAI_API_KEY not configured' });
-  }
-
-  // Set up SSE
-  res.setHeader('Content-Type', 'text/event-stream');
-  res.setHeader('Cache-Control', 'no-cache');
-  res.setHeader('Connection', 'keep-alive');
-  res.setHeader('Access-Control-Allow-Origin', '*');
-
-  const sendEvent = (event, data) => {
-    res.write(`event: ${event}\ndata: ${JSON.stringify(data)}\n\n`);
-  };
-
-  const startTime = Date.now();
-  let totalVideos = 1;
-
-  try {
-    // Phase 1: Get info
-    sendEvent('status', { message: 'Fetching video info...', phase: 'info', percent: 0 });
-    const hasPlaylist = url.includes('list=');
-    const info = await getInfo(url, hasPlaylist);
-
-    totalVideos = info._type === 'playlist' ? (info.entries?.length || 1) : 1;
-    sendEvent('info', {
-      title: info.title,
-      type: info._type || 'video',
-      totalVideos,
-      playlistTitle: info._type === 'playlist' ? info.title : null,
-    });
-
-    // Phase 2: Download (0-33%)
-    sendEvent('status', { message: 'Downloading...', phase: 'downloading', percent: 5 });
-    console.log(`[Summarize Pipeline] Downloading: ${url}`);
-
-    let videosDownloaded = 0;
-    const downloadResult = await download(url, {
-      outputDir: outputPath || OUTPUT_DIR,
-      onDownloadProgress: (progress) => {
-        const videoProgress = progress.percent || 0;
-        const overallPercent = ((videosDownloaded + (videoProgress / 100)) / totalVideos) * 33;
-
-        sendEvent('progress', {
-          percent: Math.round(overallPercent * 10) / 10,
-          phase: 'downloading',
-          phaseLabel: 'Downloading',
-          title: progress.title,
-          speed: progress.speed,
-          currentVideo: progress.videoIndex || videosDownloaded + 1,
-          totalVideos,
-        });
-      },
-      onVideoComplete: (video) => {
-        videosDownloaded++;
-        sendEvent('video-complete', {
-          title: video.title,
-          phase: 'downloading',
-          videosCompleted: videosDownloaded,
-          totalVideos,
-        });
-      },
-    });
-
-    // Phase 3: Transcribe (33-66%)
-    sendEvent('status', { message: 'Transcribing...', phase: 'transcribing', percent: 33 });
-    console.log(`[Summarize Pipeline] Transcribing ${downloadResult.successCount} files`);
-
-    const successfulDownloads = downloadResult.videos.filter(v => v.success);
-    const transcribeResults = [];
-
-    for (let i = 0; i < successfulDownloads.length; i++) {
-      const video = successfulDownloads[i];
-      const percent = 33 + ((i / successfulDownloads.length) * 33);
-
-      sendEvent('progress', {
-        percent: Math.round(percent * 10) / 10,
-        phase: 'transcribing',
-        phaseLabel: 'Transcribing',
-        title: video.title,
-        currentVideo: i + 1,
-        totalVideos: successfulDownloads.length,
-      });
-
-      try {
-        const result = await transcribeAndSave(video.filePath, {
-          responseFormat: 'text',
-          outputFormat: 'txt',
-          model,
-          outputDir: outputPath,
-        });
-        transcribeResults.push({ ...result, title: video.title, success: true });
-
-        sendEvent('transcribe-complete', {
-          title: video.title,
-          success: true,
-          videosCompleted: i + 1,
-          totalVideos: successfulDownloads.length,
-        });
-      } catch (error) {
-        transcribeResults.push({ title: video.title, success: false, error: error.message });
-        sendEvent('transcribe-complete', {
-          title: video.title,
-          success: false,
-          error: error.message,
-        });
-      }
-    }
-
-    // Phase 4: Summarize (66-100%)
-    sendEvent('status', { message: 'Summarizing with GPT-5.1...', phase: 'summarizing', percent: 66 });
-    console.log(`[Summarize Pipeline] Summarizing ${transcribeResults.filter(t => t.success).length} transcriptions`);
-
-    const summaryResults = [];
-    const successfulTranscriptions = transcribeResults.filter(t => t.success);
-
-    for (let i = 0; i < successfulTranscriptions.length; i++) {
-      const transcription = successfulTranscriptions[i];
-      const percent = 66 + ((i / successfulTranscriptions.length) * 34);
-
-      sendEvent('progress', {
-        percent: Math.round(percent * 10) / 10,
-        phase: 'summarizing',
-        phaseLabel: 'Summarizing',
-        title: transcription.title,
-        currentVideo: i + 1,
-        totalVideos: successfulTranscriptions.length,
-      });
-
-      try {
-        const result = await summarizeFile(transcription.transcriptionPath, { style, language, model: 'gpt-5.1', outputDir: outputPath });
-        summaryResults.push({
-          title: transcription.title,
-          success: true,
-          summary: result.summary,
-          summaryPath: result.summaryPath,
-          summaryUrl: `/files/${path.basename(result.summaryPath)}`,
-          transcriptionUrl: `/files/${path.basename(transcription.transcriptionPath)}`,
-          audioUrl: transcription.filePath ? `/files/${path.basename(transcription.filePath)}` : null,
-        });
-
-        sendEvent('summarize-complete', {
-          title: transcription.title,
-          success: true,
-          videosCompleted: i + 1,
-          totalVideos: successfulTranscriptions.length,
-        });
-      } catch (error) {
-        summaryResults.push({
-          title: transcription.title,
-          success: false,
-          error: error.message,
-          transcriptionUrl: `/files/${path.basename(transcription.transcriptionPath)}`,
-        });
-        sendEvent('summarize-complete', {
-          title: transcription.title,
-          success: false,
-          error: error.message,
-        });
-      }
-    }
-
-    // Final result
-    sendEvent('complete', {
-      success: true,
-      playlistTitle: downloadResult.playlistTitle,
-      totalVideos: downloadResult.totalVideos,
-      downloadedCount: downloadResult.successCount,
-      transcribedCount: transcribeResults.filter(t => t.success).length,
-      summarizedCount: summaryResults.filter(s => s.success).length,
-      totalTime: Math.round((Date.now() - startTime) / 1000),
-      results: summaryResults,
-    });
-
-  } catch (error) {
-    console.error(`[Summarize Pipeline] Error: ${error.message}`);
-    sendEvent('error', { message: error.message });
-  } finally {
-    res.end();
-  }
-});
-
-app.listen(PORT, () => {
-  console.log(`Server running on http://localhost:${PORT}`);
-  console.log('\nEndpoints:');
-  console.log('  GET  /health           - Health check');
-  console.log('  GET  /info?url=        - Get video/playlist info');
-  console.log('  POST /download         - Download as MP3');
-  console.log('  POST /transcribe       - Transcribe audio file');
-  console.log('  POST /process          - Download + transcribe');
-  console.log('  POST /summarize        - Summarize text (GPT-5.1)');
-  console.log('  POST /summarize-file   - Summarize files (GPT-5.1)');
-  console.log('  GET  /summarize-stream - Full pipeline: Download + Transcribe + Summarize');
-  console.log('  GET  /files-list       - List downloaded files');
-  console.log('  GET  /files/<name>     - Serve downloaded files');
-});
+import express from 'express';
+import cors from 'cors';
+import dotenv from 'dotenv';
+import path from 'path';
+import fs from 'fs';
+import { fileURLToPath } from 'url';
+import multer from 'multer';
+import { download, getInfo } from './services/youtube.js';
+import { transcribeFile, transcribeAndSave, transcribeMultiple } from './services/transcription.js';
+import { translateText, translateFile, translateMultiple, getLanguages } from './services/translation.js';
+import { summarizeText, summarizeFile, getSummaryStyles } from './services/summarize.js';
+import { convertToMP3, convertMultipleToMP3, getSupportedFormats } from './services/conversion.js';
+
+dotenv.config();
+
+const app = express();
+const PORT = process.env.PORT || 8888;
+const OUTPUT_DIR = process.env.OUTPUT_DIR || './output';
+
+// Ensure output directory exists
+if (!fs.existsSync(OUTPUT_DIR)) {
+  fs.mkdirSync(OUTPUT_DIR, { recursive: true });
+}
+
+// Configure multer for file uploads
+const storage = multer.diskStorage({
+  destination: (req, file, cb) => {
+    cb(null, OUTPUT_DIR);
+  },
+  filename: (req, file, cb) => {
+    // Keep original filename but sanitize it
+    const safeName = file.originalname.replace(/[^a-zA-Z0-9._-]/g, '_');
+    cb(null, safeName);
+  }
+});
+
+const upload = multer({
+  storage,
+  fileFilter: (req, file, cb) => {
+    const allowedTypes = ['audio/mpeg', 'audio/mp3', 'audio/wav', 'audio/m4a', 'audio/ogg', 'audio/flac', 'audio/x-m4a'];
+    if (allowedTypes.includes(file.mimetype) || file.originalname.match(/\.(mp3|wav|m4a|ogg|flac)$/i)) {
+      cb(null, true);
+    } else {
+      cb(new Error('Invalid file type. Only audio files are allowed.'));
+    }
+  }
+});
+
+// Upload handler for text files (for translation)
+const uploadText = multer({
+  storage,
+  fileFilter: (req, file, cb) => {
+    if (file.mimetype === 'text/plain' || file.originalname.endsWith('.txt')) {
+      cb(null, true);
+    } else {
+      cb(new Error('Invalid file type. Only text files (.txt) are allowed.'));
+    }
+  }
+});
+
+// Upload handler for video/audio files (for conversion)
+const uploadVideo = multer({
+  storage,
+  fileFilter: (req, file, cb) => {
+    const videoTypes = ['video/mp4', 'video/avi', 'video/x-msvideo', 'video/quicktime', 'video/x-matroska', 'video/webm'];
+    const audioTypes = ['audio/m4a', 'audio/x-m4a', 'audio/wav', 'audio/flac', 'audio/ogg', 'audio/aac'];
+    const videoExtensions = /\.(mp4|avi|mkv|mov|wmv|flv|webm|m4v|m4a|wav|flac|ogg|aac)$/i;
+
+    if (videoTypes.includes(file.mimetype) || audioTypes.includes(file.mimetype) || file.originalname.match(videoExtensions)) {
+      cb(null, true);
+    } else {
+      cb(new Error('Invalid file type. Only video/audio files are allowed.'));
+    }
+  }
+});
+
+app.use(cors());
+app.use(express.json());
+
+// Set permissive CSP for development
+app.use((req, res, next) => {
+  res.setHeader(
+    'Content-Security-Policy',
+    "default-src 'self'; script-src 'self' 'unsafe-inline'; style-src 'self' 'unsafe-inline'; img-src 'self' data:; connect-src 'self'"
+  );
+  next();
+});
+
+// Serve static files (HTML interface)
+const __filename = fileURLToPath(import.meta.url);
+const __dirname = path.dirname(__filename);
+app.use(express.static(path.join(__dirname, '../public')));
+
+// Serve downloaded files
+app.use('/files', express.static(OUTPUT_DIR));
+
+// API info endpoint
+app.get('/api', (req, res) => {
+  res.json({
+    name: 'Video to MP3 Transcriptor API',
+    version: '1.0.0',
+    endpoints: {
+      'GET /health': 'Health check',
+      'GET /info?url=': 'Get video/playlist info',
+      'POST /download': 'Download as MP3',
+      'POST /transcribe': 'Transcribe audio file',
+      'POST /process': 'Download + transcribe',
+      'GET /files-list': 'List downloaded files',
+      'GET /files/<name>': 'Serve downloaded files',
+    },
+  });
+});
+
+// Health check
+app.get('/health', (req, res) => {
+  res.json({ status: 'ok', timestamp: new Date().toISOString() });
+});
+
+/**
+ * GET /info?url=<youtube_url>
+ * Get info about a video or playlist
+ */
+app.get('/info', async (req, res) => {
+  try {
+    const { url } = req.query;
+
+    if (!url) {
+      return res.status(400).json({ error: 'URL parameter required' });
+    }
+
+    // Check if URL contains playlist parameter
+    const hasPlaylist = url.includes('list=');
+    const info = await getInfo(url, hasPlaylist);
+
+    res.json({
+      success: true,
+      title: info.title,
+      type: info._type || 'video',
+      duration: info.duration,
+      channel: info.channel,
+      entries: info._type === 'playlist'
+        ? info.entries?.map(e => ({ id: e.id, title: e.title }))
+        : null,
+      videoCount: info._type === 'playlist' ? info.entries?.length : 1,
+    });
+  } catch (error) {
+    res.status(500).json({ error: error.message });
+  }
+});
+
+/**
+ * GET /download-stream
+ * Download with SSE progress updates
+ * Query: url (required), outputPath (optional)
+ */
+app.get('/download-stream', async (req, res) => {
+  const { url, outputPath } = req.query;
+
+  if (!url) {
+    return res.status(400).json({ error: 'URL parameter required' });
+  }
+
+  // Set up SSE
+  res.setHeader('Content-Type', 'text/event-stream');
+  res.setHeader('Cache-Control', 'no-cache');
+  res.setHeader('Connection', 'keep-alive');
+  res.setHeader('Access-Control-Allow-Origin', '*');
+
+  const sendEvent = (event, data) => {
+    res.write(`event: ${event}\ndata: ${JSON.stringify(data)}\n\n`);
+  };
+
+  // Track timing for estimation
+  const startTime = Date.now();
+  let videosCompleted = 0;
+  let totalVideos = 1;
+  const videoTimes = [];
+
+  try {
+    // First, get info to know total videos
+    sendEvent('status', { message: 'Fetching video info...', phase: 'info' });
+    const hasPlaylist = url.includes('list=');
+    const info = await getInfo(url, hasPlaylist);
+
+    totalVideos = info._type === 'playlist' ? (info.entries?.length || 1) : 1;
+    sendEvent('info', {
+      title: info.title,
+      type: info._type || 'video',
+      totalVideos,
+      playlistTitle: info._type === 'playlist' ? info.title : null,
+    });
+
+    console.log(`Downloading: ${url}`);
+
+    let videoStartTime = Date.now();
+
+    const result = await download(url, {
+      outputDir: outputPath || OUTPUT_DIR,
+      onDownloadProgress: (progress) => {
+        // Calculate overall progress
+        const videoProgress = progress.percent || 0;
+        const overallPercent = ((videosCompleted + (videoProgress / 100)) / totalVideos) * 100;
+
+        // Estimate remaining time
+        let estimatedRemaining = null;
+        if (videosCompleted > 0 && videoTimes.length > 0) {
+          const avgTimePerVideo = videoTimes.reduce((a, b) => a + b, 0) / videoTimes.length;
+          const remainingVideos = totalVideos - videosCompleted - (videoProgress / 100);
+          estimatedRemaining = Math.round(avgTimePerVideo * remainingVideos / 1000);
+        } else if (progress.eta) {
+          // Parse ETA from yt-dlp (format: MM:SS)
+          const [mins, secs] = progress.eta.split(':').map(Number);
+          const currentVideoRemaining = mins * 60 + secs;
+          const remainingVideos = totalVideos - videosCompleted - 1;
+          // Estimate based on current video
+          if (videoProgress > 10) {
+            const elapsed = (Date.now() - videoStartTime) / 1000;
+            const estimatedVideoTime = (elapsed / videoProgress) * 100;
+            estimatedRemaining = Math.round(currentVideoRemaining + (remainingVideos * estimatedVideoTime));
+          }
+        }
+
+        sendEvent('progress', {
+          percent: Math.round(overallPercent * 10) / 10,
+          videoPercent: Math.round(videoProgress * 10) / 10,
+          currentVideo: progress.videoIndex || 1,
+          totalVideos: progress.totalVideos || totalVideos,
+          title: progress.title,
+          speed: progress.speed,
+          eta: progress.eta,
+          estimatedRemaining,
+          phase: 'downloading',
+        });
+      },
+      onVideoComplete: (video) => {
+        const videoTime = Date.now() - videoStartTime;
+        videoTimes.push(videoTime);
+        videosCompleted++;
+        videoStartTime = Date.now();
+
+        sendEvent('video-complete', {
+          title: video.title,
+          success: video.success,
+          videosCompleted,
+          totalVideos,
+        });
+      },
+    });
+
+    // Send final result
+    sendEvent('complete', {
+      success: true,
+      playlistTitle: result.playlistTitle,
+      totalVideos: result.totalVideos,
+      successCount: result.successCount,
+      failCount: result.failCount,
+      totalTime: Math.round((Date.now() - startTime) / 1000),
+      videos: result.videos.map(v => ({
+        success: v.success,
+        title: v.title,
+        filePath: v.filePath,
+        fileUrl: v.filePath ? `/files/${path.basename(v.filePath)}` : null,
+        error: v.error,
+      })),
+    });
+
+  } catch (error) {
+    sendEvent('error', { message: error.message });
+  } finally {
+    res.end();
+  }
+});
+
+/**
+ * POST /download
+ * Download a video or playlist as MP3 (non-streaming version)
+ * Body: { url: string, outputPath?: string }
+ */
+app.post('/download', async (req, res) => {
+  try {
+    const { url, outputPath } = req.body;
+    const outputDir = outputPath || OUTPUT_DIR;
+
+    if (!url) {
+      return res.status(400).json({ error: 'URL required in request body' });
+    }
+
+    console.log(`Downloading: ${url}`);
+    const result = await download(url, { outputDir });
+
+    res.json({
+      success: true,
+      playlistTitle: result.playlistTitle,
+      totalVideos: result.totalVideos,
+      successCount: result.successCount,
+      failCount: result.failCount,
+      videos: result.videos.map(v => ({
+        success: v.success,
+        title: v.title,
+        filePath: v.filePath,
+        fileUrl: v.filePath ? `/files/${path.basename(v.filePath)}` : null,
+        error: v.error,
+      })),
+    });
+  } catch (error) {
+    res.status(500).json({ error: error.message });
+  }
+});
+
+/**
+ * POST /transcribe
+ * Transcribe an existing audio file
+ * Body: { filePath: string, language?: string, format?: string, outputPath?: string }
+ */
+app.post('/transcribe', async (req, res) => {
+  try {
+    const { filePath, language, format = 'txt', model = 'gpt-4o-mini-transcribe', outputPath } = req.body;
+
+    if (!filePath) {
+      return res.status(400).json({ error: 'filePath required in request body' });
+    }
+
+    if (!process.env.OPENAI_API_KEY) {
+      return res.status(500).json({ error: 'OPENAI_API_KEY not configured' });
+    }
+
+    console.log(`Transcribing: ${filePath} with model ${model}`);
+    const result = await transcribeAndSave(filePath, {
+      language,
+      responseFormat: format === 'txt' ? 'text' : format,
+      outputFormat: format,
+      model,
+      outputDir: outputPath,
+    });
+
+    res.json({
+      success: true,
+      filePath: result.filePath,
+      transcriptionPath: result.transcriptionPath,
+      transcriptionUrl: `/files/${path.basename(result.transcriptionPath)}`,
+      text: result.text,
+    });
+  } catch (error) {
+    res.status(500).json({ error: error.message });
+  }
+});
+
+/**
+ * POST /upload-transcribe
+ * Upload audio files and transcribe them
+ * Body: { language?: string, model?: string, outputPath?: string }
+ */
+app.post('/upload-transcribe', upload.array('files', 50), async (req, res) => {
+  try {
+    if (!process.env.OPENAI_API_KEY) {
+      return res.status(500).json({ error: 'OPENAI_API_KEY not configured' });
+    }
+
+    if (!req.files || req.files.length === 0) {
+      return res.status(400).json({ error: 'No files uploaded' });
+    }
+
+    const { language, model = 'gpt-4o-mini-transcribe', outputPath } = req.body;
+    const results = [];
+
+    console.log(`Transcribing ${req.files.length} uploaded files with model ${model}`);
+
+    for (let i = 0; i < req.files.length; i++) {
+      const file = req.files[i];
+      console.log(`[${i + 1}/${req.files.length}] Transcribing: ${file.originalname}`);
+
+      try {
+        const result = await transcribeAndSave(file.path, {
+          language: language || undefined,
+          responseFormat: 'text',
+          outputFormat: 'txt',
+          model,
+          outputDir: outputPath,
+        });
+
+        results.push({
+          success: true,
+          fileName: file.originalname,
+          filePath: file.path,
+          transcriptionPath: result.transcriptionPath,
+          transcriptionUrl: `/files/${path.basename(result.transcriptionPath)}`,
+          text: result.text,
+        });
+      } catch (error) {
+        console.error(`Failed to transcribe ${file.originalname}: ${error.message}`);
+        results.push({
+          success: false,
+          fileName: file.originalname,
+          error: error.message,
+        });
+      }
+    }
+
+    res.json({
+      success: true,
+      totalFiles: req.files.length,
+      successCount: results.filter(r => r.success).length,
+      failCount: results.filter(r => !r.success).length,
+      results,
+    });
+  } catch (error) {
+    res.status(500).json({ error: error.message });
+  }
+});
+
+/**
+ * POST /convert-to-mp3
+ * Upload video/audio files and convert them to MP3
+ */
+app.post('/convert-to-mp3', uploadVideo.array('files', 50), async (req, res) => {
+  try {
+    if (!req.files || req.files.length === 0) {
+      return res.status(400).json({ error: 'No files uploaded' });
+    }
+
+    const { bitrate = '192k', quality = '2' } = req.body;
+    const results = [];
+
+    console.log(`Converting ${req.files.length} files to MP3`);
+
+    for (let i = 0; i < req.files.length; i++) {
+      const file = req.files[i];
+      console.log(`[${i + 1}/${req.files.length}] Converting: ${file.originalname}`);
+
+      try {
+        const result = await convertToMP3(file.path, {
+          outputDir: OUTPUT_DIR,
+          bitrate,
+          quality,
+        });
+
+        results.push({
+          success: true,
+          fileName: file.originalname,
+          inputPath: file.path,
+          outputPath: result.outputPath,
+          outputUrl: `/files/${path.basename(result.outputPath)}`,
+          size: result.sizeHuman,
+        });
+      } catch (error) {
+        console.error(`Failed to convert ${file.originalname}: ${error.message}`);
+        results.push({
+          success: false,
+          fileName: file.originalname,
+          error: error.message,
+        });
+      }
+    }
+
+    res.json({
+      success: true,
+      totalFiles: req.files.length,
+      successCount: results.filter(r => r.success).length,
+      failCount: results.filter(r => !r.success).length,
+      results,
+    });
+  } catch (error) {
+    res.status(500).json({ error: error.message });
+  }
+});
+
+/**
+ * GET /supported-formats
+ * Get supported video/audio formats for conversion
+ */
+app.get('/supported-formats', (req, res) => {
+  res.json({ formats: getSupportedFormats() });
+});
+
+/**
+ * GET /process-stream
+ * Download and transcribe with SSE progress updates
+ * Query: url, language?, model?, outputPath?
+ */
+app.get('/process-stream', async (req, res) => {
+  const { url, language, model = 'gpt-4o-mini-transcribe', outputPath } = req.query;
+
+  if (!url) {
+    return res.status(400).json({ error: 'URL parameter required' });
+  }
+
+  if (!process.env.OPENAI_API_KEY) {
+    return res.status(500).json({ error: 'OPENAI_API_KEY not configured' });
+  }
+
+  // Set up SSE
+  res.setHeader('Content-Type', 'text/event-stream');
+  res.setHeader('Cache-Control', 'no-cache');
+  res.setHeader('Connection', 'keep-alive');
+  res.setHeader('Access-Control-Allow-Origin', '*');
+
+  const sendEvent = (event, data) => {
+    res.write(`event: ${event}\ndata: ${JSON.stringify(data)}\n\n`);
+  };
+
+  const startTime = Date.now();
+  let videosDownloaded = 0;
+  let videosTranscribed = 0;
+  let totalVideos = 1;
+  const videoTimes = [];
+
+  try {
+    // Phase 1: Get info
+    sendEvent('status', { message: 'Fetching video info...', phase: 'info' });
+    const hasPlaylist = url.includes('list=');
+    const info = await getInfo(url, hasPlaylist);
+
+    totalVideos = info._type === 'playlist' ? (info.entries?.length || 1) : 1;
+    sendEvent('info', {
+      title: info.title,
+      type: info._type || 'video',
+      totalVideos,
+      playlistTitle: info._type === 'playlist' ? info.title : null,
+    });
+
+    // Phase 2: Download
+    console.log(`Processing: ${url}`);
+    let videoStartTime = Date.now();
+
+    const downloadResult = await download(url, {
+      outputDir: outputPath || OUTPUT_DIR,
+      onDownloadProgress: (progress) => {
+        const videoProgress = progress.percent || 0;
+        // Download is 50% of total, transcribe is other 50%
+        const overallPercent = ((videosDownloaded + (videoProgress / 100)) / totalVideos) * 50;
+
+        sendEvent('progress', {
+          percent: Math.round(overallPercent * 10) / 10,
+          videoPercent: Math.round(videoProgress * 10) / 10,
+          currentVideo: progress.videoIndex || 1,
+          totalVideos: progress.totalVideos || totalVideos,
+          title: progress.title,
+          speed: progress.speed,
+          eta: progress.eta,
+          phase: 'downloading',
+          phaseLabel: 'Downloading',
+        });
+      },
+      onVideoComplete: (video) => {
+        const videoTime = Date.now() - videoStartTime;
+        videoTimes.push(videoTime);
+        videosDownloaded++;
+        videoStartTime = Date.now();
+
+        sendEvent('video-complete', {
+          title: video.title,
+          success: video.success,
+          phase: 'downloading',
+          videosCompleted: videosDownloaded,
+          totalVideos,
+        });
+      },
+    });
+
+    // Phase 3: Transcribe
+    sendEvent('status', { message: 'Starting transcription...', phase: 'transcribing' });
+
+    const successfulDownloads = downloadResult.videos.filter(v => v.success);
+    const filePaths = successfulDownloads.map(v => v.filePath);
+    const transcribeResults = [];
+
+    for (let i = 0; i < filePaths.length; i++) {
+      const filePath = filePaths[i];
+      const video = successfulDownloads[i];
+
+      sendEvent('progress', {
+        percent: 50 + ((i / filePaths.length) * 50),
+        currentVideo: i + 1,
+        totalVideos: filePaths.length,
+        title: video.title,
+        phase: 'transcribing',
+        phaseLabel: 'Transcribing',
+      });
+
+      try {
+        const result = await transcribeAndSave(filePath, {
+          language: language || undefined,
+          responseFormat: 'text',
+          outputFormat: 'txt',
+          model,
+          outputDir: outputPath,
+        });
+        transcribeResults.push(result);
+        videosTranscribed++;
+
+        sendEvent('transcribe-complete', {
+          title: video.title,
+          success: true,
+          videosCompleted: videosTranscribed,
+          totalFiles: filePaths.length,
+        });
+      } catch (error) {
+        transcribeResults.push({
+          success: false,
+          filePath,
+          error: error.message,
+        });
+
+        sendEvent('transcribe-complete', {
+          title: video.title,
+          success: false,
+          error: error.message,
+          videosCompleted: videosTranscribed,
+          totalFiles: filePaths.length,
+        });
+      }
+    }
+
+    // Combine results
+    const combinedResults = downloadResult.videos.map(v => {
+      const transcription = transcribeResults.find(t => t.filePath === v.filePath);
+      return {
+        title: v.title,
+        downloadSuccess: v.success,
+        audioUrl: v.filePath ? `/files/${path.basename(v.filePath)}` : null,
+        transcriptionSuccess: transcription?.success || false,
+        transcriptionUrl: transcription?.transcriptionPath
+          ? `/files/${path.basename(transcription.transcriptionPath)}`
+          : null,
+        text: transcription?.text,
+        error: v.error || transcription?.error,
+      };
+    });
+
+    sendEvent('complete', {
+      success: true,
+      playlistTitle: downloadResult.playlistTitle,
+      totalVideos: downloadResult.totalVideos,
+      downloadedCount: downloadResult.successCount,
+      transcribedCount: videosTranscribed,
+      totalTime: Math.round((Date.now() - startTime) / 1000),
+      results: combinedResults,
+    });
+
+  } catch (error) {
+    sendEvent('error', { message: error.message });
+  } finally {
+    res.end();
+  }
+});
+
+/**
+ * POST /process
+ * Download and transcribe a video or playlist (non-streaming)
+ * Body: { url: string, language?: string, format?: string, outputPath?: string }
+ */
+app.post('/process', async (req, res) => {
+  try {
+    const { url, language, format = 'txt', outputPath, model = 'gpt-4o-mini-transcribe' } = req.body;
+    const outputDir = outputPath || OUTPUT_DIR;
+
+    if (!url) {
+      return res.status(400).json({ error: 'URL required in request body' });
+    }
+
+    if (!process.env.OPENAI_API_KEY) {
+      return res.status(500).json({ error: 'OPENAI_API_KEY not configured' });
+    }
+
+    // Step 1: Download
+    console.log(`Step 1: Downloading ${url}`);
+    const downloadResult = await download(url, { outputDir });
+
+    // Step 2: Transcribe
+    console.log(`Step 2: Transcribing with model ${model}...`);
+    const successfulDownloads = downloadResult.videos.filter(v => v.success);
+    const filePaths = successfulDownloads.map(v => v.filePath);
+
+    const transcribeResult = await transcribeMultiple(filePaths, {
+      language,
+      responseFormat: format === 'txt' ? 'text' : format,
+      outputFormat: format,
+      model,
+      outputDir,
+    });
+
+    // Combine results
+    const combinedResults = downloadResult.videos.map(v => {
+      const transcription = transcribeResult.results.find(
+        t => t.filePath === v.filePath
+      );
+
+      return {
+        title: v.title,
+        downloadSuccess: v.success,
+        audioPath: v.filePath,
+        audioUrl: v.filePath ? `/files/${path.basename(v.filePath)}` : null,
+        transcriptionSuccess: transcription?.success || false,
+        transcriptionPath: transcription?.transcriptionPath,
+        transcriptionUrl: transcription?.transcriptionPath
+          ? `/files/${path.basename(transcription.transcriptionPath)}`
+          : null,
+        text: transcription?.text,
+        error: v.error || transcription?.error,
+      };
+    });
+
+    res.json({
+      success: true,
+      playlistTitle: downloadResult.playlistTitle,
+      totalVideos: downloadResult.totalVideos,
+      downloadedCount: downloadResult.successCount,
+      transcribedCount: transcribeResult.successCount,
+      results: combinedResults,
+    });
+  } catch (error) {
+    res.status(500).json({ error: error.message });
+  }
+});
+
+/**
+ * GET /files
+ * List all downloaded files
+ */
+app.get('/files-list', (req, res) => {
+  try {
+    if (!fs.existsSync(OUTPUT_DIR)) {
+      return res.json({ files: [] });
+    }
+
+    const files = fs.readdirSync(OUTPUT_DIR).map(file => ({
+      name: file,
+      url: `/files/${file}`,
+      path: path.join(OUTPUT_DIR, file),
+    }));
+
+    res.json({ files });
+  } catch (error) {
+    res.status(500).json({ error: error.message });
+  }
+});
+
+/**
+ * GET /languages
+ * Get available translation languages
+ */
+app.get('/languages', (req, res) => {
+  res.json({ languages: getLanguages() });
+});
+
+/**
+ * POST /translate
+ * Translate text
+ * Body: { text: string, targetLang: string, sourceLang?: string }
+ */
+app.post('/translate', async (req, res) => {
+  try {
+    const { text, targetLang, sourceLang } = req.body;
+
+    if (!text) {
+      return res.status(400).json({ error: 'text required in request body' });
+    }
+    if (!targetLang) {
+      return res.status(400).json({ error: 'targetLang required in request body' });
+    }
+
+    if (!process.env.OPENAI_API_KEY) {
+      return res.status(500).json({ error: 'OPENAI_API_KEY not configured' });
+    }
+
+    console.log(`Translating text to ${targetLang}`);
+    const result = await translateText(text, targetLang, sourceLang);
+
+    res.json({
+      success: true,
+      ...result,
+    });
+  } catch (error) {
+    res.status(500).json({ error: error.message });
+  }
+});
+
+/**
+ * POST /translate-file
+ * Translate uploaded text files
+ * Body: { targetLang: string, sourceLang?: string, outputPath?: string }
+ */
+app.post('/translate-file', uploadText.array('files', 50), async (req, res) => {
+  try {
+    if (!process.env.OPENAI_API_KEY) {
+      return res.status(500).json({ error: 'OPENAI_API_KEY not configured' });
+    }
+
+    if (!req.files || req.files.length === 0) {
+      return res.status(400).json({ error: 'No files uploaded' });
+    }
+
+    const { targetLang, sourceLang, outputPath } = req.body;
+
+    if (!targetLang) {
+      return res.status(400).json({ error: 'targetLang required' });
+    }
+
+    const results = [];
+    console.log(`Translating ${req.files.length} files to ${targetLang}`);
+
+    for (let i = 0; i < req.files.length; i++) {
+      const file = req.files[i];
+      console.log(`[${i + 1}/${req.files.length}] Translating: ${file.originalname}`);
+
+      try {
+        const result = await translateFile(file.path, targetLang, sourceLang || null, outputPath);
+        results.push({
+          success: true,
+          fileName: file.originalname,
+          translationPath: result.translationPath,
+          translationUrl: `/files/${path.basename(result.translationPath)}`,
+          translatedText: result.translatedText,
+        });
+      } catch (error) {
+        console.error(`Failed to translate ${file.originalname}: ${error.message}`);
+        results.push({
+          success: false,
+          fileName: file.originalname,
+          error: error.message,
+        });
+      }
+    }
+
+    res.json({
+      success: true,
+      totalFiles: req.files.length,
+      successCount: results.filter(r => r.success).length,
+      failCount: results.filter(r => !r.success).length,
+      results,
+    });
+  } catch (error) {
+    res.status(500).json({ error: error.message });
+  }
+});
+
+/**
+ * GET /summary-styles
+ * Get available summary styles
+ */
+app.get('/summary-styles', (req, res) => {
+  res.json({ styles: getSummaryStyles() });
+});
+
+/**
+ * POST /summarize
+ * Summarize text using GPT-5.1
+ * Body: { text: string, style?: string, language?: string, model?: string }
+ */
+app.post('/summarize', async (req, res) => {
+  try {
+    const { text, style = 'concise', language = 'same', model = 'gpt-5.1' } = req.body;
+
+    if (!text) {
+      return res.status(400).json({ error: 'text required in request body' });
+    }
+
+    if (!process.env.OPENAI_API_KEY) {
+      return res.status(500).json({ error: 'OPENAI_API_KEY not configured' });
+    }
+
+    console.log(`Summarizing text with ${model} (style: ${style})`);
+    const result = await summarizeText(text, { style, language, model });
+
+    res.json({
+      success: true,
+      ...result,
+    });
+  } catch (error) {
+    res.status(500).json({ error: error.message });
+  }
+});
+
+/**
+ * POST /summarize-file
+ * Summarize uploaded text files using GPT-5.1
+ * Body: { style?: string, language?: string, model?: string, outputPath?: string }
+ */
+app.post('/summarize-file', uploadText.array('files', 50), async (req, res) => {
+  try {
+    if (!process.env.OPENAI_API_KEY) {
+      return res.status(500).json({ error: 'OPENAI_API_KEY not configured' });
+    }
+
+    if (!req.files || req.files.length === 0) {
+      return res.status(400).json({ error: 'No files uploaded' });
+    }
+
+    const { style = 'concise', language = 'same', model = 'gpt-5.1', outputPath } = req.body;
+    const results = [];
+
+    console.log(`Summarizing ${req.files.length} files with ${model}`);
+
+    for (let i = 0; i < req.files.length; i++) {
+      const file = req.files[i];
+      console.log(`[${i + 1}/${req.files.length}] Summarizing: ${file.originalname}`);
+
+      try {
+        const result = await summarizeFile(file.path, { style, language, model, outputDir: outputPath });
+        results.push({
+          success: true,
+          fileName: file.originalname,
+          summaryPath: result.summaryPath,
+          summaryUrl: `/files/${path.basename(result.summaryPath)}`,
+          summary: result.summary,
+          model: result.model,
+          chunks: result.chunks,
+        });
+      } catch (error) {
+        console.error(`Failed to summarize ${file.originalname}: ${error.message}`);
+        results.push({
+          success: false,
+          fileName: file.originalname,
+          error: error.message,
+        });
+      }
+    }
+
+    res.json({
+      success: true,
+      totalFiles: req.files.length,
+      successCount: results.filter(r => r.success).length,
+      failCount: results.filter(r => !r.success).length,
+      results,
+    });
+  } catch (error) {
+    res.status(500).json({ error: error.message });
+  }
+});
+
+/**
+ * GET /summarize-stream
+ * Full pipeline: Download -> Transcribe -> Summarize with SSE progress
+ * Query: url, style?, language?, model?, outputPath?
+ */
+app.get('/summarize-stream', async (req, res) => {
+  const { url, style = 'concise', language = 'same', model = 'gpt-4o-mini-transcribe', outputPath } = req.query;
+
+  if (!url) {
+    return res.status(400).json({ error: 'URL parameter required' });
+  }
+
+  if (!process.env.OPENAI_API_KEY) {
+    return res.status(500).json({ error: 'OPENAI_API_KEY not configured' });
+  }
+
+  // Set up SSE
+  res.setHeader('Content-Type', 'text/event-stream');
+  res.setHeader('Cache-Control', 'no-cache');
+  res.setHeader('Connection', 'keep-alive');
+  res.setHeader('Access-Control-Allow-Origin', '*');
+
+  const sendEvent = (event, data) => {
+    res.write(`event: ${event}\ndata: ${JSON.stringify(data)}\n\n`);
+  };
+
+  const startTime = Date.now();
+  let totalVideos = 1;
+
+  try {
+    // Phase 1: Get info
+    sendEvent('status', { message: 'Fetching video info...', phase: 'info', percent: 0 });
+    const hasPlaylist = url.includes('list=');
+    const info = await getInfo(url, hasPlaylist);
+
+    totalVideos = info._type === 'playlist' ? (info.entries?.length || 1) : 1;
+    sendEvent('info', {
+      title: info.title,
+      type: info._type || 'video',
+      totalVideos,
+      playlistTitle: info._type === 'playlist' ? info.title : null,
+    });
+
+    // Phase 2: Download (0-33%)
+    sendEvent('status', { message: 'Downloading...', phase: 'downloading', percent: 5 });
+    console.log(`[Summarize Pipeline] Downloading: ${url}`);
+
+    let videosDownloaded = 0;
+    const downloadResult = await download(url, {
+      outputDir: outputPath || OUTPUT_DIR,
+      onDownloadProgress: (progress) => {
+        const videoProgress = progress.percent || 0;
+        const overallPercent = ((videosDownloaded + (videoProgress / 100)) / totalVideos) * 33;
+
+        sendEvent('progress', {
+          percent: Math.round(overallPercent * 10) / 10,
+          phase: 'downloading',
+          phaseLabel: 'Downloading',
+          title: progress.title,
+          speed: progress.speed,
+          currentVideo: progress.videoIndex || videosDownloaded + 1,
+          totalVideos,
+        });
+      },
+      onVideoComplete: (video) => {
+        videosDownloaded++;
+        sendEvent('video-complete', {
+          title: video.title,
+          phase: 'downloading',
+          videosCompleted: videosDownloaded,
+          totalVideos,
+        });
+      },
+    });
+
+    // Phase 3: Transcribe (33-66%)
+    sendEvent('status', { message: 'Transcribing...', phase: 'transcribing', percent: 33 });
+    console.log(`[Summarize Pipeline] Transcribing ${downloadResult.successCount} files`);
+
+    const successfulDownloads = downloadResult.videos.filter(v => v.success);
+    const transcribeResults = [];
+
+    for (let i = 0; i < successfulDownloads.length; i++) {
+      const video = successfulDownloads[i];
+      const percent = 33 + ((i / successfulDownloads.length) * 33);
+
+      sendEvent('progress', {
+        percent: Math.round(percent * 10) / 10,
+        phase: 'transcribing',
+        phaseLabel: 'Transcribing',
+        title: video.title,
+        currentVideo: i + 1,
+        totalVideos: successfulDownloads.length,
+      });
+
+      try {
+        const result = await transcribeAndSave(video.filePath, {
+          responseFormat: 'text',
+          outputFormat: 'txt',
+          model,
+          outputDir: outputPath,
+        });
+        transcribeResults.push({ ...result, title: video.title, success: true });
+
+        sendEvent('transcribe-complete', {
+          title: video.title,
+          success: true,
+          videosCompleted: i + 1,
+          totalVideos: successfulDownloads.length,
+        });
+      } catch (error) {
+        transcribeResults.push({ title: video.title, success: false, error: error.message });
+        sendEvent('transcribe-complete', {
+          title: video.title,
+          success: false,
+          error: error.message,
+        });
+      }
+    }
+
+    // Phase 4: Summarize (66-100%)
+    sendEvent('status', { message: 'Summarizing with GPT-5.1...', phase: 'summarizing', percent: 66 });
+    console.log(`[Summarize Pipeline] Summarizing ${transcribeResults.filter(t => t.success).length} transcriptions`);
+
+    const summaryResults = [];
+    const successfulTranscriptions = transcribeResults.filter(t => t.success);
+
+    for (let i = 0; i < successfulTranscriptions.length; i++) {
+      const transcription = successfulTranscriptions[i];
+      const percent = 66 + ((i / successfulTranscriptions.length) * 34);
+
+      sendEvent('progress', {
+        percent: Math.round(percent * 10) / 10,
+        phase: 'summarizing',
+        phaseLabel: 'Summarizing',
+        title: transcription.title,
+        currentVideo: i + 1,
+        totalVideos: successfulTranscriptions.length,
+      });
+
+      try {
+        const result = await summarizeFile(transcription.transcriptionPath, { style, language, model: 'gpt-5.1', outputDir: outputPath });
+        summaryResults.push({
+          title: transcription.title,
+          success: true,
+          summary: result.summary,
+          summaryPath: result.summaryPath,
+          summaryUrl: `/files/${path.basename(result.summaryPath)}`,
+          transcriptionUrl: `/files/${path.basename(transcription.transcriptionPath)}`,
+          audioUrl: transcription.filePath ? `/files/${path.basename(transcription.filePath)}` : null,
+        });
+
+        sendEvent('summarize-complete', {
+          title: transcription.title,
+          success: true,
+          videosCompleted: i + 1,
+          totalVideos: successfulTranscriptions.length,
+        });
+      } catch (error) {
+        summaryResults.push({
+          title: transcription.title,
+          success: false,
+          error: error.message,
+          transcriptionUrl: `/files/${path.basename(transcription.transcriptionPath)}`,
+        });
+        sendEvent('summarize-complete', {
+          title: transcription.title,
+          success: false,
+          error: error.message,
+        });
+      }
+    }
+
+    // Final result
+    sendEvent('complete', {
+      success: true,
+      playlistTitle: downloadResult.playlistTitle,
+      totalVideos: downloadResult.totalVideos,
+      downloadedCount: downloadResult.successCount,
+      transcribedCount: transcribeResults.filter(t => t.success).length,
+      summarizedCount: summaryResults.filter(s => s.success).length,
+      totalTime: Math.round((Date.now() - startTime) / 1000),
+      results: summaryResults,
+    });
+
+  } catch (error) {
+    console.error(`[Summarize Pipeline] Error: ${error.message}`);
+    sendEvent('error', { message: error.message });
+  } finally {
+    res.end();
+  }
+});
+
+app.listen(PORT, () => {
+  console.log(`Server running on http://localhost:${PORT}`);
+  console.log('\nEndpoints:');
+  console.log('  GET  /health           - Health check');
+  console.log('  GET  /info?url=        - Get video/playlist info');
+  console.log('  POST /download         - Download as MP3');
+  console.log('  POST /transcribe       - Transcribe audio file');
+  console.log('  POST /process          - Download + transcribe');
+  console.log('  POST /summarize        - Summarize text (GPT-5.1)');
+  console.log('  POST /summarize-file   - Summarize files (GPT-5.1)');
+  console.log('  GET  /summarize-stream - Full pipeline: Download + Transcribe + Summarize');
+  console.log('  GET  /files-list       - List downloaded files');
+  console.log('  GET  /files/<name>     - Serve downloaded files');
+});
diff --git a/src/services/conversion.js b/src/services/conversion.js
index 9b5b23b..2fe0ff7 100644
--- a/src/services/conversion.js
+++ b/src/services/conversion.js
@@ -1,145 +1,145 @@
-import { exec } from 'child_process';
-import { promisify } from 'util';
-import path from 'path';
-import fs from 'fs';
-
-const execPromise = promisify(exec);
-
-/**
- * Convert a video/audio file to MP3 using FFmpeg
- * @param {string} inputPath - Path to input file
- * @param {object} options - Conversion options
- * @param {string} options.outputDir - Output directory (default: same as input)
- * @param {string} options.bitrate - Audio bitrate (default: 192k)
- * @param {string} options.quality - Audio quality 0-9 (default: 2, where 0 is best)
- * @returns {Promise<object>} Conversion result with output path
- */
-export async function convertToMP3(inputPath, options = {}) {
-  const {
-    outputDir = path.dirname(inputPath),
-    bitrate = '192k',
-    quality = '2',
-  } = options;
-
-  // Ensure input file exists
-  if (!fs.existsSync(inputPath)) {
-    throw new Error(`Input file not found: ${inputPath}`);
-  }
-
-  // Generate output path
-  const inputFilename = path.basename(inputPath, path.extname(inputPath));
-  const outputPath = path.join(outputDir, `${inputFilename}.mp3`);
-
-  // Check if output already exists
-  if (fs.existsSync(outputPath)) {
-    // Add timestamp to make it unique
-    const timestamp = Date.now();
-    const uniqueOutputPath = path.join(outputDir, `${inputFilename}_${timestamp}.mp3`);
-    return convertToMP3Internal(inputPath, uniqueOutputPath, bitrate, quality);
-  }
-
-  return convertToMP3Internal(inputPath, outputPath, bitrate, quality);
-}
-
-/**
- * Internal conversion function
- */
-async function convertToMP3Internal(inputPath, outputPath, bitrate, quality) {
-  try {
-    // FFmpeg command to convert to MP3
-    // -i: input file
-    // -vn: no video (audio only)
-    // -ar 44100: audio sample rate 44.1kHz
-    // -ac 2: stereo
-    // -b:a: audio bitrate
-    // -q:a: audio quality (VBR)
-    const command = `ffmpeg -i "${inputPath}" -vn -ar 44100 -ac 2 -b:a ${bitrate} -q:a ${quality} "${outputPath}"`;
-
-    console.log(`Converting: ${path.basename(inputPath)} -> ${path.basename(outputPath)}`);
-
-    const { stdout, stderr } = await execPromise(command);
-
-    // Verify output file was created
-    if (!fs.existsSync(outputPath)) {
-      throw new Error('Conversion failed: output file not created');
-    }
-
-    const stats = fs.statSync(outputPath);
-
-    return {
-      success: true,
-      inputPath,
-      outputPath,
-      filename: path.basename(outputPath),
-      size: stats.size,
-      sizeHuman: formatBytes(stats.size),
-    };
-  } catch (error) {
-    console.error(`Conversion error: ${error.message}`);
-    throw new Error(`FFmpeg conversion failed: ${error.message}`);
-  }
-}
-
-/**
- * Convert multiple files to MP3
- * @param {string[]} inputPaths - Array of input file paths
- * @param {object} options - Conversion options
- * @returns {Promise<object>} Batch conversion results
- */
-export async function convertMultipleToMP3(inputPaths, options = {}) {
-  const results = [];
-  let successCount = 0;
-  let failCount = 0;
-
-  for (let i = 0; i < inputPaths.length; i++) {
-    const inputPath = inputPaths[i];
-    console.log(`[${i + 1}/${inputPaths.length}] Converting: ${path.basename(inputPath)}`);
-
-    try {
-      const result = await convertToMP3(inputPath, options);
-      results.push({ ...result, index: i });
-      successCount++;
-    } catch (error) {
-      results.push({
-        success: false,
-        inputPath,
-        error: error.message,
-        index: i,
-      });
-      failCount++;
-      console.error(`Failed to convert ${path.basename(inputPath)}: ${error.message}`);
-    }
-  }
-
-  return {
-    totalFiles: inputPaths.length,
-    successCount,
-    failCount,
-    results,
-  };
-}
-
-/**
- * Format bytes to human readable format
- */
-function formatBytes(bytes, decimals = 2) {
-  if (bytes === 0) return '0 Bytes';
-
-  const k = 1024;
-  const dm = decimals < 0 ? 0 : decimals;
-  const sizes = ['Bytes', 'KB', 'MB', 'GB'];
-
-  const i = Math.floor(Math.log(bytes) / Math.log(k));
-
-  return parseFloat((bytes / Math.pow(k, i)).toFixed(dm)) + ' ' + sizes[i];
-}
-
-/**
- * Get supported input formats
- */
-export function getSupportedFormats() {
-  return {
-    video: ['.mp4', '.avi', '.mkv', '.mov', '.wmv', '.flv', '.webm', '.m4v'],
-    audio: ['.m4a', '.wav', '.flac', '.ogg', '.aac', '.wma', '.opus'],
-  };
-}
+import { exec } from 'child_process';
+import { promisify } from 'util';
+import path from 'path';
+import fs from 'fs';
+
+const execPromise = promisify(exec);
+
+/**
+ * Convert a video/audio file to MP3 using FFmpeg
+ * @param {string} inputPath - Path to input file
+ * @param {object} options - Conversion options
+ * @param {string} options.outputDir - Output directory (default: same as input)
+ * @param {string} options.bitrate - Audio bitrate (default: 192k)
+ * @param {string} options.quality - Audio quality 0-9 (default: 2, where 0 is best)
+ * @returns {Promise<object>} Conversion result with output path
+ */
+export async function convertToMP3(inputPath, options = {}) {
+  const {
+    outputDir = path.dirname(inputPath),
+    bitrate = '192k',
+    quality = '2',
+  } = options;
+
+  // Ensure input file exists
+  if (!fs.existsSync(inputPath)) {
+    throw new Error(`Input file not found: ${inputPath}`);
+  }
+
+  // Generate output path
+  const inputFilename = path.basename(inputPath, path.extname(inputPath));
+  const outputPath = path.join(outputDir, `${inputFilename}.mp3`);
+
+  // Check if output already exists
+  if (fs.existsSync(outputPath)) {
+    // Add timestamp to make it unique
+    const timestamp = Date.now();
+    const uniqueOutputPath = path.join(outputDir, `${inputFilename}_${timestamp}.mp3`);
+    return convertToMP3Internal(inputPath, uniqueOutputPath, bitrate, quality);
+  }
+
+  return convertToMP3Internal(inputPath, outputPath, bitrate, quality);
+}
+
+/**
+ * Internal conversion function
+ */
+async function convertToMP3Internal(inputPath, outputPath, bitrate, quality) {
+  try {
+    // FFmpeg command to convert to MP3
+    // -i: input file
+    // -vn: no video (audio only)
+    // -ar 44100: audio sample rate 44.1kHz
+    // -ac 2: stereo
+    // -b:a: audio bitrate
+    // -q:a: audio quality (VBR)
+    const command = `ffmpeg -i "${inputPath}" -vn -ar 44100 -ac 2 -b:a ${bitrate} -q:a ${quality} "${outputPath}"`;
+
+    console.log(`Converting: ${path.basename(inputPath)} -> ${path.basename(outputPath)}`);
+
+    const { stdout, stderr } = await execPromise(command);
+
+    // Verify output file was created
+    if (!fs.existsSync(outputPath)) {
+      throw new Error('Conversion failed: output file not created');
+    }
+
+    const stats = fs.statSync(outputPath);
+
+    return {
+      success: true,
+      inputPath,
+      outputPath,
+      filename: path.basename(outputPath),
+      size: stats.size,
+      sizeHuman: formatBytes(stats.size),
+    };
+  } catch (error) {
+    console.error(`Conversion error: ${error.message}`);
+    throw new Error(`FFmpeg conversion failed: ${error.message}`);
+  }
+}
+
+/**
+ * Convert multiple files to MP3
+ * @param {string[]} inputPaths - Array of input file paths
+ * @param {object} options - Conversion options
+ * @returns {Promise<object>} Batch conversion results
+ */
+export async function convertMultipleToMP3(inputPaths, options = {}) {
+  const results = [];
+  let successCount = 0;
+  let failCount = 0;
+
+  for (let i = 0; i < inputPaths.length; i++) {
+    const inputPath = inputPaths[i];
+    console.log(`[${i + 1}/${inputPaths.length}] Converting: ${path.basename(inputPath)}`);
+
+    try {
+      const result = await convertToMP3(inputPath, options);
+      results.push({ ...result, index: i });
+      successCount++;
+    } catch (error) {
+      results.push({
+        success: false,
+        inputPath,
+        error: error.message,
+        index: i,
+      });
+      failCount++;
+      console.error(`Failed to convert ${path.basename(inputPath)}: ${error.message}`);
+    }
+  }
+
+  return {
+    totalFiles: inputPaths.length,
+    successCount,
+    failCount,
+    results,
+  };
+}
+
+/**
+ * Format bytes to human readable format
+ */
+function formatBytes(bytes, decimals = 2) {
+  if (bytes === 0) return '0 Bytes';
+
+  const k = 1024;
+  const dm = decimals < 0 ? 0 : decimals;
+  const sizes = ['Bytes', 'KB', 'MB', 'GB'];
+
+  const i = Math.floor(Math.log(bytes) / Math.log(k));
+
+  return parseFloat((bytes / Math.pow(k, i)).toFixed(dm)) + ' ' + sizes[i];
+}
+
+/**
+ * Get supported input formats
+ */
+export function getSupportedFormats() {
+  return {
+    video: ['.mp4', '.avi', '.mkv', '.mov', '.wmv', '.flv', '.webm', '.m4v'],
+    audio: ['.m4a', '.wav', '.flac', '.ogg', '.aac', '.wma', '.opus'],
+  };
+}
diff --git a/src/services/summarize.js b/src/services/summarize.js
index 4acb8bd..44ee794 100644
--- a/src/services/summarize.js
+++ b/src/services/summarize.js
@@ -1,195 +1,195 @@
-import OpenAI from 'openai';
-import fs from 'fs';
-import path from 'path';
-
-let openai = null;
-
-// Max characters per chunk for summarization
-const MAX_CHUNK_CHARS = 30000;
-
-/**
- * Get OpenAI client (lazy initialization)
- */
-function getOpenAI() {
-  if (!openai) {
-    if (!process.env.OPENAI_API_KEY) {
-      throw new Error('OPENAI_API_KEY environment variable is not set');
-    }
-    openai = new OpenAI({ apiKey: process.env.OPENAI_API_KEY });
-  }
-  return openai;
-}
-
-/**
- * Summarize text using GPT-4o
- */
-export async function summarizeText(text, options = {}) {
-  const {
-    model = 'gpt-5.1', // GPT-5.1 - latest OpenAI model (Nov 2025)
-    language = 'same', // 'same' = same as input, or specify language code
-    style = 'concise', // 'concise', 'detailed', 'bullet'
-    maxLength = null, // optional max length in words
-  } = options;
-
-  const client = getOpenAI();
-
-  let styleInstruction = '';
-  switch (style) {
-    case 'detailed':
-      styleInstruction = 'Provide a detailed summary that captures all important points and nuances.';
-      break;
-    case 'bullet':
-      styleInstruction = 'Provide the summary as bullet points, highlighting the key points.';
-      break;
-    case 'concise':
-    default:
-      styleInstruction = 'Provide a concise summary that captures the main points.';
-  }
-
-  let languageInstruction = '';
-  if (language === 'same') {
-    languageInstruction = 'Write the summary in the same language as the input text.';
-  } else {
-    languageInstruction = `Write the summary in ${language}.`;
-  }
-
-  let lengthInstruction = '';
-  if (maxLength) {
-    lengthInstruction = `Keep the summary under ${maxLength} words.`;
-  }
-
-  const systemPrompt = `You are an expert summarizer. ${styleInstruction} ${languageInstruction} ${lengthInstruction}
-Focus on the most important information and main ideas. Be accurate and objective.`;
-
-  // Handle long texts by chunking
-  if (text.length > MAX_CHUNK_CHARS) {
-    return await summarizeLongText(text, { model, systemPrompt, style });
-  }
-
-  const response = await client.chat.completions.create({
-    model,
-    messages: [
-      { role: 'system', content: systemPrompt },
-      { role: 'user', content: `Please summarize the following text:\n\n${text}` },
-    ],
-    temperature: 0.3,
-  });
-
-  return {
-    summary: response.choices[0].message.content,
-    model,
-    style,
-    inputLength: text.length,
-    chunks: 1,
-  };
-}
-
-/**
- * Summarize long text by chunking and combining summaries
- */
-async function summarizeLongText(text, options) {
-  const { model, systemPrompt, style } = options;
-  const client = getOpenAI();
-
-  // Split into chunks
-  const chunks = [];
-  let currentChunk = '';
-  const sentences = text.split(/(?<=[.!?。！？\n])\s*/);
-
-  for (const sentence of sentences) {
-    if ((currentChunk + sentence).length > MAX_CHUNK_CHARS && currentChunk) {
-      chunks.push(currentChunk.trim());
-      currentChunk = sentence;
-    } else {
-      currentChunk += ' ' + sentence;
-    }
-  }
-  if (currentChunk.trim()) {
-    chunks.push(currentChunk.trim());
-  }
-
-  console.log(`Summarizing ${chunks.length} chunks...`);
-
-  // Summarize each chunk
-  const chunkSummaries = [];
-  for (let i = 0; i < chunks.length; i++) {
-    console.log(`[${i + 1}/${chunks.length}] Summarizing chunk...`);
-    const response = await client.chat.completions.create({
-      model,
-      messages: [
-        { role: 'system', content: systemPrompt },
-        { role: 'user', content: `Please summarize the following text (part ${i + 1} of ${chunks.length}):\n\n${chunks[i]}` },
-      ],
-      temperature: 0.3,
-    });
-    chunkSummaries.push(response.choices[0].message.content);
-  }
-
-  // Combine summaries if multiple chunks
-  if (chunkSummaries.length === 1) {
-    return {
-      summary: chunkSummaries[0],
-      model,
-      style,
-      inputLength: text.length,
-      chunks: 1,
-    };
-  }
-
-  // Create final combined summary
-  const combinedText = chunkSummaries.join('\n\n---\n\n');
-  const finalResponse = await client.chat.completions.create({
-    model,
-    messages: [
-      { role: 'system', content: `You are an expert summarizer. Combine and synthesize the following partial summaries into a single coherent ${style} summary. Remove redundancy and ensure a smooth flow.` },
-      { role: 'user', content: `Please combine these summaries into one:\n\n${combinedText}` },
-    ],
-    temperature: 0.3,
-  });
-
-  return {
-    summary: finalResponse.choices[0].message.content,
-    model,
-    style,
-    inputLength: text.length,
-    chunks: chunks.length,
-  };
-}
-
-/**
- * Summarize a text file
- */
-export async function summarizeFile(filePath, options = {}) {
-  if (!fs.existsSync(filePath)) {
-    throw new Error(`File not found: ${filePath}`);
-  }
-
-  const { outputDir, ...otherOptions } = options;
-
-  const text = fs.readFileSync(filePath, 'utf-8');
-  const result = await summarizeText(text, otherOptions);
-
-  // Save summary to file
-  const dir = outputDir || path.dirname(filePath);
-  const baseName = path.basename(filePath, path.extname(filePath));
-  const summaryPath = path.join(dir, `${baseName}_summary.txt`);
-
-  fs.writeFileSync(summaryPath, result.summary, 'utf-8');
-
-  return {
-    ...result,
-    filePath,
-    summaryPath,
-  };
-}
-
-/**
- * Get available summary styles
- */
-export function getSummaryStyles() {
-  return {
-    concise: 'A brief summary capturing main points',
-    detailed: 'A comprehensive summary with nuances',
-    bullet: 'Key points as bullet points',
-  };
-}
+import OpenAI from 'openai';
+import fs from 'fs';
+import path from 'path';
+
+let openai = null;
+
+// Max characters per chunk for summarization
+const MAX_CHUNK_CHARS = 30000;
+
+/**
+ * Get OpenAI client (lazy initialization)
+ */
+function getOpenAI() {
+  if (!openai) {
+    if (!process.env.OPENAI_API_KEY) {
+      throw new Error('OPENAI_API_KEY environment variable is not set');
+    }
+    openai = new OpenAI({ apiKey: process.env.OPENAI_API_KEY });
+  }
+  return openai;
+}
+
+/**
+ * Summarize text using GPT-4o
+ */
+export async function summarizeText(text, options = {}) {
+  const {
+    model = 'gpt-5.1', // GPT-5.1 - latest OpenAI model (Nov 2025)
+    language = 'same', // 'same' = same as input, or specify language code
+    style = 'concise', // 'concise', 'detailed', 'bullet'
+    maxLength = null, // optional max length in words
+  } = options;
+
+  const client = getOpenAI();
+
+  let styleInstruction = '';
+  switch (style) {
+    case 'detailed':
+      styleInstruction = 'Provide a detailed summary that captures all important points and nuances.';
+      break;
+    case 'bullet':
+      styleInstruction = 'Provide the summary as bullet points, highlighting the key points.';
+      break;
+    case 'concise':
+    default:
+      styleInstruction = 'Provide a concise summary that captures the main points.';
+  }
+
+  let languageInstruction = '';
+  if (language === 'same') {
+    languageInstruction = 'Write the summary in the same language as the input text.';
+  } else {
+    languageInstruction = `Write the summary in ${language}.`;
+  }
+
+  let lengthInstruction = '';
+  if (maxLength) {
+    lengthInstruction = `Keep the summary under ${maxLength} words.`;
+  }
+
+  const systemPrompt = `You are an expert summarizer. ${styleInstruction} ${languageInstruction} ${lengthInstruction}
+Focus on the most important information and main ideas. Be accurate and objective.`;
+
+  // Handle long texts by chunking
+  if (text.length > MAX_CHUNK_CHARS) {
+    return await summarizeLongText(text, { model, systemPrompt, style });
+  }
+
+  const response = await client.chat.completions.create({
+    model,
+    messages: [
+      { role: 'system', content: systemPrompt },
+      { role: 'user', content: `Please summarize the following text:\n\n${text}` },
+    ],
+    temperature: 0.3,
+  });
+
+  return {
+    summary: response.choices[0].message.content,
+    model,
+    style,
+    inputLength: text.length,
+    chunks: 1,
+  };
+}
+
+/**
+ * Summarize long text by chunking and combining summaries
+ */
+async function summarizeLongText(text, options) {
+  const { model, systemPrompt, style } = options;
+  const client = getOpenAI();
+
+  // Split into chunks
+  const chunks = [];
+  let currentChunk = '';
+  const sentences = text.split(/(?<=[.!?。！？\n])\s*/);
+
+  for (const sentence of sentences) {
+    if ((currentChunk + sentence).length > MAX_CHUNK_CHARS && currentChunk) {
+      chunks.push(currentChunk.trim());
+      currentChunk = sentence;
+    } else {
+      currentChunk += ' ' + sentence;
+    }
+  }
+  if (currentChunk.trim()) {
+    chunks.push(currentChunk.trim());
+  }
+
+  console.log(`Summarizing ${chunks.length} chunks...`);
+
+  // Summarize each chunk
+  const chunkSummaries = [];
+  for (let i = 0; i < chunks.length; i++) {
+    console.log(`[${i + 1}/${chunks.length}] Summarizing chunk...`);
+    const response = await client.chat.completions.create({
+      model,
+      messages: [
+        { role: 'system', content: systemPrompt },
+        { role: 'user', content: `Please summarize the following text (part ${i + 1} of ${chunks.length}):\n\n${chunks[i]}` },
+      ],
+      temperature: 0.3,
+    });
+    chunkSummaries.push(response.choices[0].message.content);
+  }
+
+  // Combine summaries if multiple chunks
+  if (chunkSummaries.length === 1) {
+    return {
+      summary: chunkSummaries[0],
+      model,
+      style,
+      inputLength: text.length,
+      chunks: 1,
+    };
+  }
+
+  // Create final combined summary
+  const combinedText = chunkSummaries.join('\n\n---\n\n');
+  const finalResponse = await client.chat.completions.create({
+    model,
+    messages: [
+      { role: 'system', content: `You are an expert summarizer. Combine and synthesize the following partial summaries into a single coherent ${style} summary. Remove redundancy and ensure a smooth flow.` },
+      { role: 'user', content: `Please combine these summaries into one:\n\n${combinedText}` },
+    ],
+    temperature: 0.3,
+  });
+
+  return {
+    summary: finalResponse.choices[0].message.content,
+    model,
+    style,
+    inputLength: text.length,
+    chunks: chunks.length,
+  };
+}
+
+/**
+ * Summarize a text file
+ */
+export async function summarizeFile(filePath, options = {}) {
+  if (!fs.existsSync(filePath)) {
+    throw new Error(`File not found: ${filePath}`);
+  }
+
+  const { outputDir, ...otherOptions } = options;
+
+  const text = fs.readFileSync(filePath, 'utf-8');
+  const result = await summarizeText(text, otherOptions);
+
+  // Save summary to file
+  const dir = outputDir || path.dirname(filePath);
+  const baseName = path.basename(filePath, path.extname(filePath));
+  const summaryPath = path.join(dir, `${baseName}_summary.txt`);
+
+  fs.writeFileSync(summaryPath, result.summary, 'utf-8');
+
+  return {
+    ...result,
+    filePath,
+    summaryPath,
+  };
+}
+
+/**
+ * Get available summary styles
+ */
+export function getSummaryStyles() {
+  return {
+    concise: 'A brief summary capturing main points',
+    detailed: 'A comprehensive summary with nuances',
+    bullet: 'Key points as bullet points',
+  };
+}
diff --git a/src/services/transcription.js b/src/services/transcription.js
index b3b5f28..61e65f4 100644
--- a/src/services/transcription.js
+++ b/src/services/transcription.js
@@ -1,178 +1,178 @@
-import OpenAI from 'openai';
-import fs from 'fs';
-import path from 'path';
-
-let openai = null;
-
-// Available transcription models
-const MODELS = {
-  'gpt-4o-transcribe': {
-    name: 'gpt-4o-transcribe',
-    formats: ['json', 'text'],
-    supportsLanguage: true,
-  },
-  'gpt-4o-mini-transcribe': {
-    name: 'gpt-4o-mini-transcribe',
-    formats: ['json', 'text'],
-    supportsLanguage: true,
-  },
-  'whisper-1': {
-    name: 'whisper-1',
-    formats: ['json', 'text', 'srt', 'vtt', 'verbose_json'],
-    supportsLanguage: true,
-  },
-};
-
-const DEFAULT_MODEL = 'gpt-4o-mini-transcribe';
-
-/**
- * Get OpenAI client (lazy initialization)
- */
-function getOpenAI() {
-  if (!openai) {
-    if (!process.env.OPENAI_API_KEY) {
-      throw new Error('OPENAI_API_KEY environment variable is not set');
-    }
-    openai = new OpenAI({
-      apiKey: process.env.OPENAI_API_KEY,
-    });
-  }
-  return openai;
-}
-
-/**
- * Get available models
- */
-export function getAvailableModels() {
-  return Object.keys(MODELS);
-}
-
-/**
- * Transcribe an audio file using OpenAI API
- * @param {string} filePath - Path to audio file
- * @param {Object} options - Transcription options
- * @param {string} options.language - Language code (e.g., 'en', 'fr', 'es', 'zh')
- * @param {string} options.responseFormat - Output format: 'json' or 'text' (gpt-4o models), or 'srt'/'vtt' (whisper-1 only)
- * @param {string} options.prompt - Optional context prompt for better accuracy
- * @param {string} options.model - Model to use (default: gpt-4o-transcribe)
- */
-export async function transcribeFile(filePath, options = {}) {
-  const {
-    language = null, // Auto-detect if null
-    responseFormat = 'text', // json or text for gpt-4o models
-    prompt = null, // Optional context prompt
-    model = DEFAULT_MODEL,
-  } = options;
-
-  if (!fs.existsSync(filePath)) {
-    throw new Error(`File not found: ${filePath}`);
-  }
-
-  const modelConfig = MODELS[model] || MODELS[DEFAULT_MODEL];
-  const actualModel = modelConfig.name;
-
-  // Validate response format for model
-  let actualFormat = responseFormat;
-  if (!modelConfig.formats.includes(responseFormat)) {
-    console.warn(`Format '${responseFormat}' not supported by ${actualModel}, using 'text'`);
-    actualFormat = 'text';
-  }
-
-  try {
-    const transcriptionOptions = {
-      file: fs.createReadStream(filePath),
-      model: actualModel,
-      response_format: actualFormat,
-    };
-
-    if (language) {
-      transcriptionOptions.language = language;
-    }
-
-    if (prompt) {
-      transcriptionOptions.prompt = prompt;
-    }
-
-    console.log(`Using model: ${actualModel}, format: ${actualFormat}${language ? `, language: ${language}` : ''}`);
-
-    const transcription = await getOpenAI().audio.transcriptions.create(transcriptionOptions);
-
-    return {
-      success: true,
-      filePath,
-      text: actualFormat === 'json' || actualFormat === 'verbose_json'
-        ? transcription.text
-        : transcription,
-      format: actualFormat,
-      model: actualModel,
-    };
-  } catch (error) {
-    throw new Error(`Transcription failed: ${error.message}`);
-  }
-}
-
-/**
- * Transcribe and save to file
- */
-export async function transcribeAndSave(filePath, options = {}) {
-  const { outputFormat = 'txt', outputDir = null } = options;
-
-  const result = await transcribeFile(filePath, options);
-
-  // Determine output path
-  const baseName = path.basename(filePath, path.extname(filePath));
-  const outputPath = path.join(
-    outputDir || path.dirname(filePath),
-    `${baseName}.${outputFormat}`
-  );
-
-  // Save transcription
-  fs.writeFileSync(outputPath, result.text, 'utf-8');
-
-  return {
-    ...result,
-    transcriptionPath: outputPath,
-  };
-}
-
-/**
- * Transcribe multiple files
- */
-export async function transcribeMultiple(filePaths, options = {}) {
-  const { onProgress, onFileComplete } = options;
-  const results = [];
-
-  for (let i = 0; i < filePaths.length; i++) {
-    const filePath = filePaths[i];
-
-    if (onProgress) {
-      onProgress({ current: i + 1, total: filePaths.length, filePath });
-    }
-
-    console.log(`[${i + 1}/${filePaths.length}] Transcribing: ${path.basename(filePath)}`);
-
-    try {
-      const result = await transcribeAndSave(filePath, options);
-      results.push(result);
-
-      if (onFileComplete) {
-        onFileComplete(result);
-      }
-    } catch (error) {
-      console.error(`Failed to transcribe ${filePath}: ${error.message}`);
-      results.push({
-        success: false,
-        filePath,
-        error: error.message,
-      });
-    }
-  }
-
-  return {
-    success: true,
-    results,
-    totalFiles: filePaths.length,
-    successCount: results.filter(r => r.success).length,
-    failCount: results.filter(r => !r.success).length,
-  };
-}
+import OpenAI from 'openai';
+import fs from 'fs';
+import path from 'path';
+
+let openai = null;
+
+// Available transcription models
+const MODELS = {
+  'gpt-4o-transcribe': {
+    name: 'gpt-4o-transcribe',
+    formats: ['json', 'text'],
+    supportsLanguage: true,
+  },
+  'gpt-4o-mini-transcribe': {
+    name: 'gpt-4o-mini-transcribe',
+    formats: ['json', 'text'],
+    supportsLanguage: true,
+  },
+  'whisper-1': {
+    name: 'whisper-1',
+    formats: ['json', 'text', 'srt', 'vtt', 'verbose_json'],
+    supportsLanguage: true,
+  },
+};
+
+const DEFAULT_MODEL = 'gpt-4o-mini-transcribe';
+
+/**
+ * Get OpenAI client (lazy initialization)
+ */
+function getOpenAI() {
+  if (!openai) {
+    if (!process.env.OPENAI_API_KEY) {
+      throw new Error('OPENAI_API_KEY environment variable is not set');
+    }
+    openai = new OpenAI({
+      apiKey: process.env.OPENAI_API_KEY,
+    });
+  }
+  return openai;
+}
+
+/**
+ * Get available models
+ */
+export function getAvailableModels() {
+  return Object.keys(MODELS);
+}
+
+/**
+ * Transcribe an audio file using OpenAI API
+ * @param {string} filePath - Path to audio file
+ * @param {Object} options - Transcription options
+ * @param {string} options.language - Language code (e.g., 'en', 'fr', 'es', 'zh')
+ * @param {string} options.responseFormat - Output format: 'json' or 'text' (gpt-4o models), or 'srt'/'vtt' (whisper-1 only)
+ * @param {string} options.prompt - Optional context prompt for better accuracy
+ * @param {string} options.model - Model to use (default: gpt-4o-transcribe)
+ */
+export async function transcribeFile(filePath, options = {}) {
+  const {
+    language = null, // Auto-detect if null
+    responseFormat = 'text', // json or text for gpt-4o models
+    prompt = null, // Optional context prompt
+    model = DEFAULT_MODEL,
+  } = options;
+
+  if (!fs.existsSync(filePath)) {
+    throw new Error(`File not found: ${filePath}`);
+  }
+
+  const modelConfig = MODELS[model] || MODELS[DEFAULT_MODEL];
+  const actualModel = modelConfig.name;
+
+  // Validate response format for model
+  let actualFormat = responseFormat;
+  if (!modelConfig.formats.includes(responseFormat)) {
+    console.warn(`Format '${responseFormat}' not supported by ${actualModel}, using 'text'`);
+    actualFormat = 'text';
+  }
+
+  try {
+    const transcriptionOptions = {
+      file: fs.createReadStream(filePath),
+      model: actualModel,
+      response_format: actualFormat,
+    };
+
+    if (language) {
+      transcriptionOptions.language = language;
+    }
+
+    if (prompt) {
+      transcriptionOptions.prompt = prompt;
+    }
+
+    console.log(`Using model: ${actualModel}, format: ${actualFormat}${language ? `, language: ${language}` : ''}`);
+
+    const transcription = await getOpenAI().audio.transcriptions.create(transcriptionOptions);
+
+    return {
+      success: true,
+      filePath,
+      text: actualFormat === 'json' || actualFormat === 'verbose_json'
+        ? transcription.text
+        : transcription,
+      format: actualFormat,
+      model: actualModel,
+    };
+  } catch (error) {
+    throw new Error(`Transcription failed: ${error.message}`);
+  }
+}
+
+/**
+ * Transcribe and save to file
+ */
+export async function transcribeAndSave(filePath, options = {}) {
+  const { outputFormat = 'txt', outputDir = null } = options;
+
+  const result = await transcribeFile(filePath, options);
+
+  // Determine output path
+  const baseName = path.basename(filePath, path.extname(filePath));
+  const outputPath = path.join(
+    outputDir || path.dirname(filePath),
+    `${baseName}.${outputFormat}`
+  );
+
+  // Save transcription
+  fs.writeFileSync(outputPath, result.text, 'utf-8');
+
+  return {
+    ...result,
+    transcriptionPath: outputPath,
+  };
+}
+
+/**
+ * Transcribe multiple files
+ */
+export async function transcribeMultiple(filePaths, options = {}) {
+  const { onProgress, onFileComplete } = options;
+  const results = [];
+
+  for (let i = 0; i < filePaths.length; i++) {
+    const filePath = filePaths[i];
+
+    if (onProgress) {
+      onProgress({ current: i + 1, total: filePaths.length, filePath });
+    }
+
+    console.log(`[${i + 1}/${filePaths.length}] Transcribing: ${path.basename(filePath)}`);
+
+    try {
+      const result = await transcribeAndSave(filePath, options);
+      results.push(result);
+
+      if (onFileComplete) {
+        onFileComplete(result);
+      }
+    } catch (error) {
+      console.error(`Failed to transcribe ${filePath}: ${error.message}`);
+      results.push({
+        success: false,
+        filePath,
+        error: error.message,
+      });
+    }
+  }
+
+  return {
+    success: true,
+    results,
+    totalFiles: filePaths.length,
+    successCount: results.filter(r => r.success).length,
+    failCount: results.filter(r => !r.success).length,
+  };
+}
diff --git a/src/services/translation.js b/src/services/translation.js
index efbe1c0..e8fa424 100644
--- a/src/services/translation.js
+++ b/src/services/translation.js
@@ -1,271 +1,271 @@
-import OpenAI from 'openai';
-import fs from 'fs';
-import path from 'path';
-
-let openai = null;
-
-// Max characters per chunk (~6000 tokens ≈ 24000 characters for most languages)
-const MAX_CHUNK_CHARS = 20000;
-
-const LANGUAGES = {
-  en: 'English',
-  fr: 'French',
-  es: 'Spanish',
-  de: 'German',
-  it: 'Italian',
-  pt: 'Portuguese',
-  zh: 'Chinese',
-  ja: 'Japanese',
-  ko: 'Korean',
-  ru: 'Russian',
-  ar: 'Arabic',
-  hi: 'Hindi',
-  nl: 'Dutch',
-  pl: 'Polish',
-  tr: 'Turkish',
-  vi: 'Vietnamese',
-  th: 'Thai',
-  sv: 'Swedish',
-  da: 'Danish',
-  fi: 'Finnish',
-  no: 'Norwegian',
-  cs: 'Czech',
-  el: 'Greek',
-  he: 'Hebrew',
-  id: 'Indonesian',
-  ms: 'Malay',
-  ro: 'Romanian',
-  uk: 'Ukrainian',
-};
-
-// Sentence ending patterns for different languages
-const SENTENCE_ENDINGS = /[.!?。！？｡\n]/g;
-
-/**
- * Get OpenAI client (lazy initialization)
- */
-function getOpenAI() {
-  if (!openai) {
-    if (!process.env.OPENAI_API_KEY) {
-      throw new Error('OPENAI_API_KEY environment variable is not set');
-    }
-    openai = new OpenAI({
-      apiKey: process.env.OPENAI_API_KEY,
-    });
-  }
-  return openai;
-}
-
-/**
- * Split text into chunks at sentence boundaries
- * @param {string} text - Text to split
- * @param {number} maxChars - Maximum characters per chunk
- * @returns {string[]} Array of text chunks
- */
-function splitIntoChunks(text, maxChars = MAX_CHUNK_CHARS) {
-  if (text.length <= maxChars) {
-    return [text];
-  }
-
-  const chunks = [];
-  let currentPos = 0;
-
-  while (currentPos < text.length) {
-    let endPos = currentPos + maxChars;
-
-    // If we're at the end, just take the rest
-    if (endPos >= text.length) {
-      chunks.push(text.slice(currentPos));
-      break;
-    }
-
-    // Find the last sentence ending before maxChars
-    const searchText = text.slice(currentPos, endPos);
-    let lastSentenceEnd = -1;
-
-    // Find all sentence endings in the search range
-    let match;
-    SENTENCE_ENDINGS.lastIndex = 0;
-    while ((match = SENTENCE_ENDINGS.exec(searchText)) !== null) {
-      lastSentenceEnd = match.index + 1; // Include the punctuation
-    }
-
-    // If we found a sentence ending, cut there
-    // Otherwise, look for the next sentence ending after maxChars (up to 20% more)
-    if (lastSentenceEnd > maxChars * 0.5) {
-      endPos = currentPos + lastSentenceEnd;
-    } else {
-      // Look forward for a sentence ending (up to 20% more characters)
-      const extendedSearch = text.slice(endPos, endPos + maxChars * 0.2);
-      SENTENCE_ENDINGS.lastIndex = 0;
-      const forwardMatch = SENTENCE_ENDINGS.exec(extendedSearch);
-      if (forwardMatch) {
-        endPos = endPos + forwardMatch.index + 1;
-      }
-      // If still no sentence ending found, just cut at maxChars
-    }
-
-    chunks.push(text.slice(currentPos, endPos).trim());
-    currentPos = endPos;
-
-    // Skip any leading whitespace for the next chunk
-    while (currentPos < text.length && /\s/.test(text[currentPos])) {
-      currentPos++;
-    }
-  }
-
-  return chunks.filter(chunk => chunk.length > 0);
-}
-
-/**
- * Get available languages
- */
-export function getLanguages() {
-  return LANGUAGES;
-}
-
-/**
- * Translate a single chunk of text
- */
-async function translateChunk(text, targetLanguage, sourceLanguage) {
-  const prompt = sourceLanguage
-    ? `Translate the following text from ${sourceLanguage} to ${targetLanguage}. Only output the translation, nothing else:\n\n${text}`
-    : `Translate the following text to ${targetLanguage}. Only output the translation, nothing else:\n\n${text}`;
-
-  const response = await getOpenAI().chat.completions.create({
-    model: 'gpt-4o-mini',
-    max_tokens: 16384,
-    messages: [
-      {
-        role: 'user',
-        content: prompt,
-      },
-    ],
-  });
-
-  return response.choices[0].message.content;
-}
-
-/**
- * Translate text using GPT-4o-mini with chunking for long texts
- * @param {string} text - Text to translate
- * @param {string} targetLang - Target language code (e.g., 'en', 'fr')
- * @param {string} sourceLang - Source language code (optional, auto-detect if null)
- */
-export async function translateText(text, targetLang, sourceLang = null) {
-  if (!text || !text.trim()) {
-    throw new Error('No text provided for translation');
-  }
-
-  const targetLanguage = LANGUAGES[targetLang] || targetLang;
-  const sourceLanguage = sourceLang ? (LANGUAGES[sourceLang] || sourceLang) : null;
-
-  try {
-    // Split text into chunks
-    const chunks = splitIntoChunks(text);
-
-    if (chunks.length === 1) {
-      // Single chunk - translate directly
-      const translation = await translateChunk(text, targetLanguage, sourceLanguage);
-      return {
-        success: true,
-        originalText: text,
-        translatedText: translation,
-        targetLanguage: targetLanguage,
-        sourceLanguage: sourceLanguage || 'auto-detected',
-        chunks: 1,
-      };
-    }
-
-    // Multiple chunks - translate each and combine
-    console.log(`Splitting text into ${chunks.length} chunks for translation...`);
-    const translations = [];
-
-    for (let i = 0; i < chunks.length; i++) {
-      console.log(`  Translating chunk ${i + 1}/${chunks.length} (${chunks[i].length} chars)...`);
-      const translation = await translateChunk(chunks[i], targetLanguage, sourceLanguage);
-      translations.push(translation);
-    }
-
-    const combinedTranslation = translations.join('\n\n');
-
-    return {
-      success: true,
-      originalText: text,
-      translatedText: combinedTranslation,
-      targetLanguage: targetLanguage,
-      sourceLanguage: sourceLanguage || 'auto-detected',
-      chunks: chunks.length,
-    };
-  } catch (error) {
-    throw new Error(`Translation failed: ${error.message}`);
-  }
-}
-
-/**
- * Translate a text file
- * @param {string} filePath - Path to text file
- * @param {string} targetLang - Target language code
- * @param {string} sourceLang - Source language code (optional)
- * @param {string} outputDir - Output directory (optional)
- */
-export async function translateFile(filePath, targetLang, sourceLang = null, outputDir = null) {
-  if (!fs.existsSync(filePath)) {
-    throw new Error(`File not found: ${filePath}`);
-  }
-
-  const text = fs.readFileSync(filePath, 'utf-8');
-  const result = await translateText(text, targetLang, sourceLang);
-
-  // Save translation
-  const baseName = path.basename(filePath, path.extname(filePath));
-  const outputPath = path.join(
-    outputDir || path.dirname(filePath),
-    `${baseName}_${targetLang}.txt`
-  );
-
-  fs.writeFileSync(outputPath, result.translatedText, 'utf-8');
-
-  return {
-    ...result,
-    originalPath: filePath,
-    translationPath: outputPath,
-  };
-}
-
-/**
- * Translate multiple files
- */
-export async function translateMultiple(filePaths, targetLang, sourceLang = null, outputDir = null, onProgress = null) {
-  const results = [];
-
-  for (let i = 0; i < filePaths.length; i++) {
-    const filePath = filePaths[i];
-
-    if (onProgress) {
-      onProgress({ current: i + 1, total: filePaths.length, filePath });
-    }
-
-    console.log(`[${i + 1}/${filePaths.length}] Translating: ${path.basename(filePath)}`);
-
-    try {
-      const result = await translateFile(filePath, targetLang, sourceLang, outputDir);
-      results.push(result);
-    } catch (error) {
-      console.error(`Failed to translate ${filePath}: ${error.message}`);
-      results.push({
-        success: false,
-        originalPath: filePath,
-        error: error.message,
-      });
-    }
-  }
-
-  return {
-    success: true,
-    results,
-    totalFiles: filePaths.length,
-    successCount: results.filter(r => r.success).length,
-    failCount: results.filter(r => !r.success).length,
-  };
-}
+import OpenAI from 'openai';
+import fs from 'fs';
+import path from 'path';
+
+let openai = null;
+
+// Max characters per chunk (~6000 tokens ≈ 24000 characters for most languages)
+const MAX_CHUNK_CHARS = 20000;
+
+const LANGUAGES = {
+  en: 'English',
+  fr: 'French',
+  es: 'Spanish',
+  de: 'German',
+  it: 'Italian',
+  pt: 'Portuguese',
+  zh: 'Chinese',
+  ja: 'Japanese',
+  ko: 'Korean',
+  ru: 'Russian',
+  ar: 'Arabic',
+  hi: 'Hindi',
+  nl: 'Dutch',
+  pl: 'Polish',
+  tr: 'Turkish',
+  vi: 'Vietnamese',
+  th: 'Thai',
+  sv: 'Swedish',
+  da: 'Danish',
+  fi: 'Finnish',
+  no: 'Norwegian',
+  cs: 'Czech',
+  el: 'Greek',
+  he: 'Hebrew',
+  id: 'Indonesian',
+  ms: 'Malay',
+  ro: 'Romanian',
+  uk: 'Ukrainian',
+};
+
+// Sentence ending patterns for different languages
+const SENTENCE_ENDINGS = /[.!?。！？｡\n]/g;
+
+/**
+ * Get OpenAI client (lazy initialization)
+ */
+function getOpenAI() {
+  if (!openai) {
+    if (!process.env.OPENAI_API_KEY) {
+      throw new Error('OPENAI_API_KEY environment variable is not set');
+    }
+    openai = new OpenAI({
+      apiKey: process.env.OPENAI_API_KEY,
+    });
+  }
+  return openai;
+}
+
+/**
+ * Split text into chunks at sentence boundaries
+ * @param {string} text - Text to split
+ * @param {number} maxChars - Maximum characters per chunk
+ * @returns {string[]} Array of text chunks
+ */
+function splitIntoChunks(text, maxChars = MAX_CHUNK_CHARS) {
+  if (text.length <= maxChars) {
+    return [text];
+  }
+
+  const chunks = [];
+  let currentPos = 0;
+
+  while (currentPos < text.length) {
+    let endPos = currentPos + maxChars;
+
+    // If we're at the end, just take the rest
+    if (endPos >= text.length) {
+      chunks.push(text.slice(currentPos));
+      break;
+    }
+
+    // Find the last sentence ending before maxChars
+    const searchText = text.slice(currentPos, endPos);
+    let lastSentenceEnd = -1;
+
+    // Find all sentence endings in the search range
+    let match;
+    SENTENCE_ENDINGS.lastIndex = 0;
+    while ((match = SENTENCE_ENDINGS.exec(searchText)) !== null) {
+      lastSentenceEnd = match.index + 1; // Include the punctuation
+    }
+
+    // If we found a sentence ending, cut there
+    // Otherwise, look for the next sentence ending after maxChars (up to 20% more)
+    if (lastSentenceEnd > maxChars * 0.5) {
+      endPos = currentPos + lastSentenceEnd;
+    } else {
+      // Look forward for a sentence ending (up to 20% more characters)
+      const extendedSearch = text.slice(endPos, endPos + maxChars * 0.2);
+      SENTENCE_ENDINGS.lastIndex = 0;
+      const forwardMatch = SENTENCE_ENDINGS.exec(extendedSearch);
+      if (forwardMatch) {
+        endPos = endPos + forwardMatch.index + 1;
+      }
+      // If still no sentence ending found, just cut at maxChars
+    }
+
+    chunks.push(text.slice(currentPos, endPos).trim());
+    currentPos = endPos;
+
+    // Skip any leading whitespace for the next chunk
+    while (currentPos < text.length && /\s/.test(text[currentPos])) {
+      currentPos++;
+    }
+  }
+
+  return chunks.filter(chunk => chunk.length > 0);
+}
+
+/**
+ * Get available languages
+ */
+export function getLanguages() {
+  return LANGUAGES;
+}
+
+/**
+ * Translate a single chunk of text
+ */
+async function translateChunk(text, targetLanguage, sourceLanguage) {
+  const prompt = sourceLanguage
+    ? `Translate the following text from ${sourceLanguage} to ${targetLanguage}. Only output the translation, nothing else:\n\n${text}`
+    : `Translate the following text to ${targetLanguage}. Only output the translation, nothing else:\n\n${text}`;
+
+  const response = await getOpenAI().chat.completions.create({
+    model: 'gpt-4o-mini',
+    max_tokens: 16384,
+    messages: [
+      {
+        role: 'user',
+        content: prompt,
+      },
+    ],
+  });
+
+  return response.choices[0].message.content;
+}
+
+/**
+ * Translate text using GPT-4o-mini with chunking for long texts
+ * @param {string} text - Text to translate
+ * @param {string} targetLang - Target language code (e.g., 'en', 'fr')
+ * @param {string} sourceLang - Source language code (optional, auto-detect if null)
+ */
+export async function translateText(text, targetLang, sourceLang = null) {
+  if (!text || !text.trim()) {
+    throw new Error('No text provided for translation');
+  }
+
+  const targetLanguage = LANGUAGES[targetLang] || targetLang;
+  const sourceLanguage = sourceLang ? (LANGUAGES[sourceLang] || sourceLang) : null;
+
+  try {
+    // Split text into chunks
+    const chunks = splitIntoChunks(text);
+
+    if (chunks.length === 1) {
+      // Single chunk - translate directly
+      const translation = await translateChunk(text, targetLanguage, sourceLanguage);
+      return {
+        success: true,
+        originalText: text,
+        translatedText: translation,
+        targetLanguage: targetLanguage,
+        sourceLanguage: sourceLanguage || 'auto-detected',
+        chunks: 1,
+      };
+    }
+
+    // Multiple chunks - translate each and combine
+    console.log(`Splitting text into ${chunks.length} chunks for translation...`);
+    const translations = [];
+
+    for (let i = 0; i < chunks.length; i++) {
+      console.log(`  Translating chunk ${i + 1}/${chunks.length} (${chunks[i].length} chars)...`);
+      const translation = await translateChunk(chunks[i], targetLanguage, sourceLanguage);
+      translations.push(translation);
+    }
+
+    const combinedTranslation = translations.join('\n\n');
+
+    return {
+      success: true,
+      originalText: text,
+      translatedText: combinedTranslation,
+      targetLanguage: targetLanguage,
+      sourceLanguage: sourceLanguage || 'auto-detected',
+      chunks: chunks.length,
+    };
+  } catch (error) {
+    throw new Error(`Translation failed: ${error.message}`);
+  }
+}
+
+/**
+ * Translate a text file
+ * @param {string} filePath - Path to text file
+ * @param {string} targetLang - Target language code
+ * @param {string} sourceLang - Source language code (optional)
+ * @param {string} outputDir - Output directory (optional)
+ */
+export async function translateFile(filePath, targetLang, sourceLang = null, outputDir = null) {
+  if (!fs.existsSync(filePath)) {
+    throw new Error(`File not found: ${filePath}`);
+  }
+
+  const text = fs.readFileSync(filePath, 'utf-8');
+  const result = await translateText(text, targetLang, sourceLang);
+
+  // Save translation
+  const baseName = path.basename(filePath, path.extname(filePath));
+  const outputPath = path.join(
+    outputDir || path.dirname(filePath),
+    `${baseName}_${targetLang}.txt`
+  );
+
+  fs.writeFileSync(outputPath, result.translatedText, 'utf-8');
+
+  return {
+    ...result,
+    originalPath: filePath,
+    translationPath: outputPath,
+  };
+}
+
+/**
+ * Translate multiple files
+ */
+export async function translateMultiple(filePaths, targetLang, sourceLang = null, outputDir = null, onProgress = null) {
+  const results = [];
+
+  for (let i = 0; i < filePaths.length; i++) {
+    const filePath = filePaths[i];
+
+    if (onProgress) {
+      onProgress({ current: i + 1, total: filePaths.length, filePath });
+    }
+
+    console.log(`[${i + 1}/${filePaths.length}] Translating: ${path.basename(filePath)}`);
+
+    try {
+      const result = await translateFile(filePath, targetLang, sourceLang, outputDir);
+      results.push(result);
+    } catch (error) {
+      console.error(`Failed to translate ${filePath}: ${error.message}`);
+      results.push({
+        success: false,
+        originalPath: filePath,
+        error: error.message,
+      });
+    }
+  }
+
+  return {
+    success: true,
+    results,
+    totalFiles: filePaths.length,
+    successCount: results.filter(r => r.success).length,
+    failCount: results.filter(r => !r.success).length,
+  };
+}
diff --git a/src/services/youtube.js b/src/services/youtube.js
index 55d53a5..5948d9a 100644
--- a/src/services/youtube.js
+++ b/src/services/youtube.js
@@ -1,291 +1,291 @@
-import { createRequire } from 'module';
-import path from 'path';
-import fs from 'fs';
-import { spawn } from 'child_process';
-
-// Use system yt-dlp binary (check common paths)
-const YTDLP_PATH = process.env.YTDLP_PATH || 'yt-dlp';
-
-/**
- * Execute yt-dlp command and return parsed JSON
- */
-async function ytdlp(url, args = []) {
-  return new Promise((resolve, reject) => {
-    const proc = spawn(YTDLP_PATH, [...args, url]);
-    let stdout = '';
-    let stderr = '';
-
-    proc.stdout.on('data', (data) => { stdout += data; });
-    proc.stderr.on('data', (data) => { stderr += data; });
-
-    proc.on('close', (code) => {
-      if (code === 0) {
-        try {
-          resolve(JSON.parse(stdout));
-        } catch {
-          resolve(stdout);
-        }
-      } else {
-        reject(new Error(stderr || `yt-dlp exited with code ${code}`));
-      }
-    });
-  });
-}
-
-/**
- * Execute yt-dlp command with progress callback
- */
-function ytdlpExec(url, args = [], onProgress) {
-  return new Promise((resolve, reject) => {
-    const proc = spawn(YTDLP_PATH, [...args, url]);
-    let stderr = '';
-
-    proc.stdout.on('data', (data) => {
-      const line = data.toString();
-      if (onProgress) {
-        const progressMatch = line.match(/\[download\]\s+(\d+\.?\d*)%/);
-        const etaMatch = line.match(/ETA\s+(\d+:\d+)/);
-        const speedMatch = line.match(/at\s+([\d.]+\w+\/s)/);
-
-        if (progressMatch) {
-          onProgress({
-            percent: parseFloat(progressMatch[1]),
-            eta: etaMatch ? etaMatch[1] : null,
-            speed: speedMatch ? speedMatch[1] : null,
-          });
-        }
-      }
-    });
-
-    proc.stderr.on('data', (data) => { stderr += data; });
-
-    proc.on('close', (code) => {
-      if (code === 0) {
-        resolve();
-      } else {
-        reject(new Error(stderr || `yt-dlp exited with code ${code}`));
-      }
-    });
-  });
-}
-
-const OUTPUT_DIR = process.env.OUTPUT_DIR || './output';
-
-/**
- * Sanitize filename to remove invalid characters
- */
-function sanitizeFilename(filename) {
-  return filename
-    .replace(/[<>:"/\\|?*]/g, '')
-    .replace(/\s+/g, '_')
-    .substring(0, 200);
-}
-
-/**
- * Check if URL contains a playlist parameter
- */
-function hasPlaylistParam(url) {
-  try {
-    const urlObj = new URL(url);
-    return urlObj.searchParams.has('list');
-  } catch {
-    return false;
-  }
-}
-
-/**
- * Extract playlist URL if present in the URL
- */
-function extractPlaylistUrl(url) {
-  const urlObj = new URL(url);
-  const listId = urlObj.searchParams.get('list');
-  if (listId) {
-    return `https://www.youtube.com/playlist?list=${listId}`;
-  }
-  return null;
-}
-
-/**
- * Get video/playlist info without downloading
- */
-export async function getInfo(url, forcePlaylist = false) {
-  try {
-    // If URL contains a playlist ID and we want to force playlist mode
-    const playlistUrl = extractPlaylistUrl(url);
-    const targetUrl = (forcePlaylist && playlistUrl) ? playlistUrl : url;
-
-    const info = await ytdlp(targetUrl, [
-      '--dump-single-json',
-      '--no-download',
-      '--no-warnings',
-      '--flat-playlist',
-    ]);
-    return info;
-  } catch (error) {
-    throw new Error(`Failed to get info: ${error.message}`);
-  }
-}
-
-/**
- * Check if URL is a playlist
- */
-export async function isPlaylist(url) {
-  const info = await getInfo(url);
-  return info._type === 'playlist';
-}
-
-/**
- * Download a single video as MP3
- */
-export async function downloadVideo(url, options = {}) {
-  const { outputDir = OUTPUT_DIR, onProgress, onDownloadProgress } = options;
-
-  // Ensure output directory exists
-  if (!fs.existsSync(outputDir)) {
-    fs.mkdirSync(outputDir, { recursive: true });
-  }
-
-  try {
-    // Get video info first
-    const info = await ytdlp(url, [
-      '--dump-single-json',
-      '--no-download',
-      '--no-warnings',
-    ]);
-
-    const title = sanitizeFilename(info.title);
-    const outputPath = path.join(outputDir, `${title}.mp3`);
-
-    // Download and convert to MP3 with progress
-    await ytdlpExec(url, [
-      '--extract-audio',
-      '--audio-format', 'mp3',
-      '--audio-quality', '0',
-      '-o', outputPath,
-      '--no-warnings',
-      '--newline',
-    ], (progress) => {
-      if (onDownloadProgress) {
-        onDownloadProgress({
-          ...progress,
-          title: info.title,
-        });
-      }
-    });
-
-    return {
-      success: true,
-      title: info.title,
-      duration: info.duration,
-      filePath: outputPath,
-      url: url,
-    };
-  } catch (error) {
-    throw new Error(`Failed to download: ${error.message}`);
-  }
-}
-
-/**
- * Download all videos from a playlist as MP3
- */
-export async function downloadPlaylist(url, options = {}) {
-  const { outputDir = OUTPUT_DIR, onProgress, onVideoComplete, onDownloadProgress, forcePlaylist = false } = options;
-
-  // Ensure output directory exists
-  if (!fs.existsSync(outputDir)) {
-    fs.mkdirSync(outputDir, { recursive: true });
-  }
-
-  try {
-    // Get playlist info (force playlist mode if URL has list= param)
-    const info = await getInfo(url, forcePlaylist || hasPlaylistParam(url));
-
-    if (info._type !== 'playlist') {
-      // Single video, redirect to downloadVideo
-      const result = await downloadVideo(url, { ...options, onDownloadProgress });
-      return {
-        success: true,
-        playlistTitle: result.title,
-        videos: [result],
-        totalVideos: 1,
-      };
-    }
-
-    const results = [];
-    const entries = info.entries || [];
-
-    console.log(`Playlist: ${info.title} (${entries.length} videos)`);
-
-    for (let i = 0; i < entries.length; i++) {
-      const entry = entries[i];
-      const videoUrl = entry.url || `https://www.youtube.com/watch?v=${entry.id}`;
-
-      try {
-        if (onProgress) {
-          onProgress({ current: i + 1, total: entries.length, title: entry.title });
-        }
-
-        console.log(`[${i + 1}/${entries.length}] Downloading: ${entry.title}`);
-
-        // Wrap progress callback to include playlist context
-        const wrappedProgress = onDownloadProgress ? (progress) => {
-          onDownloadProgress({
-            ...progress,
-            videoIndex: i + 1,
-            totalVideos: entries.length,
-            playlistTitle: info.title,
-          });
-        } : undefined;
-
-        const result = await downloadVideo(videoUrl, { outputDir, onDownloadProgress: wrappedProgress });
-        results.push(result);
-
-        if (onVideoComplete) {
-          onVideoComplete(result);
-        }
-      } catch (error) {
-        console.error(`Failed to download ${entry.title}: ${error.message}`);
-        results.push({
-          success: false,
-          title: entry.title,
-          url: videoUrl,
-          error: error.message,
-        });
-      }
-    }
-
-    return {
-      success: true,
-      playlistTitle: info.title,
-      videos: results,
-      totalVideos: entries.length,
-      successCount: results.filter(r => r.success).length,
-      failCount: results.filter(r => !r.success).length,
-    };
-  } catch (error) {
-    throw new Error(`Failed to download playlist: ${error.message}`);
-  }
-}
-
-/**
- * Smart download - detects if URL is video or playlist
- */
-export async function download(url, options = {}) {
-  // If URL contains list= parameter, treat it as a playlist
-  const isPlaylistUrl = hasPlaylistParam(url);
-  const info = await getInfo(url, isPlaylistUrl);
-
-  if (info._type === 'playlist') {
-    return downloadPlaylist(url, { ...options, forcePlaylist: true });
-  } else {
-    const result = await downloadVideo(url, options);
-    return {
-      success: true,
-      playlistTitle: null,
-      videos: [result],
-      totalVideos: 1,
-      successCount: 1,
-      failCount: 0,
-    };
-  }
-}
+import { createRequire } from 'module';
+import path from 'path';
+import fs from 'fs';
+import { spawn } from 'child_process';
+
+// Use system yt-dlp binary (check common paths)
+const YTDLP_PATH = process.env.YTDLP_PATH || 'yt-dlp';
+
+/**
+ * Execute yt-dlp command and return parsed JSON
+ */
+async function ytdlp(url, args = []) {
+  return new Promise((resolve, reject) => {
+    const proc = spawn(YTDLP_PATH, [...args, url]);
+    let stdout = '';
+    let stderr = '';
+
+    proc.stdout.on('data', (data) => { stdout += data; });
+    proc.stderr.on('data', (data) => { stderr += data; });
+
+    proc.on('close', (code) => {
+      if (code === 0) {
+        try {
+          resolve(JSON.parse(stdout));
+        } catch {
+          resolve(stdout);
+        }
+      } else {
+        reject(new Error(stderr || `yt-dlp exited with code ${code}`));
+      }
+    });
+  });
+}
+
+/**
+ * Execute yt-dlp command with progress callback
+ */
+function ytdlpExec(url, args = [], onProgress) {
+  return new Promise((resolve, reject) => {
+    const proc = spawn(YTDLP_PATH, [...args, url]);
+    let stderr = '';
+
+    proc.stdout.on('data', (data) => {
+      const line = data.toString();
+      if (onProgress) {
+        const progressMatch = line.match(/\[download\]\s+(\d+\.?\d*)%/);
+        const etaMatch = line.match(/ETA\s+(\d+:\d+)/);
+        const speedMatch = line.match(/at\s+([\d.]+\w+\/s)/);
+
+        if (progressMatch) {
+          onProgress({
+            percent: parseFloat(progressMatch[1]),
+            eta: etaMatch ? etaMatch[1] : null,
+            speed: speedMatch ? speedMatch[1] : null,
+          });
+        }
+      }
+    });
+
+    proc.stderr.on('data', (data) => { stderr += data; });
+
+    proc.on('close', (code) => {
+      if (code === 0) {
+        resolve();
+      } else {
+        reject(new Error(stderr || `yt-dlp exited with code ${code}`));
+      }
+    });
+  });
+}
+
+const OUTPUT_DIR = process.env.OUTPUT_DIR || './output';
+
+/**
+ * Sanitize filename to remove invalid characters
+ */
+function sanitizeFilename(filename) {
+  return filename
+    .replace(/[<>:"/\\|?*]/g, '')
+    .replace(/\s+/g, '_')
+    .substring(0, 200);
+}
+
+/**
+ * Check if URL contains a playlist parameter
+ */
+function hasPlaylistParam(url) {
+  try {
+    const urlObj = new URL(url);
+    return urlObj.searchParams.has('list');
+  } catch {
+    return false;
+  }
+}
+
+/**
+ * Extract playlist URL if present in the URL
+ */
+function extractPlaylistUrl(url) {
+  const urlObj = new URL(url);
+  const listId = urlObj.searchParams.get('list');
+  if (listId) {
+    return `https://www.youtube.com/playlist?list=${listId}`;
+  }
+  return null;
+}
+
+/**
+ * Get video/playlist info without downloading
+ */
+export async function getInfo(url, forcePlaylist = false) {
+  try {
+    // If URL contains a playlist ID and we want to force playlist mode
+    const playlistUrl = extractPlaylistUrl(url);
+    const targetUrl = (forcePlaylist && playlistUrl) ? playlistUrl : url;
+
+    const info = await ytdlp(targetUrl, [
+      '--dump-single-json',
+      '--no-download',
+      '--no-warnings',
+      '--flat-playlist',
+    ]);
+    return info;
+  } catch (error) {
+    throw new Error(`Failed to get info: ${error.message}`);
+  }
+}
+
+/**
+ * Check if URL is a playlist
+ */
+export async function isPlaylist(url) {
+  const info = await getInfo(url);
+  return info._type === 'playlist';
+}
+
+/**
+ * Download a single video as MP3
+ */
+export async function downloadVideo(url, options = {}) {
+  const { outputDir = OUTPUT_DIR, onProgress, onDownloadProgress } = options;
+
+  // Ensure output directory exists
+  if (!fs.existsSync(outputDir)) {
+    fs.mkdirSync(outputDir, { recursive: true });
+  }
+
+  try {
+    // Get video info first
+    const info = await ytdlp(url, [
+      '--dump-single-json',
+      '--no-download',
+      '--no-warnings',
+    ]);
+
+    const title = sanitizeFilename(info.title);
+    const outputPath = path.join(outputDir, `${title}.mp3`);
+
+    // Download and convert to MP3 with progress
+    await ytdlpExec(url, [
+      '--extract-audio',
+      '--audio-format', 'mp3',
+      '--audio-quality', '0',
+      '-o', outputPath,
+      '--no-warnings',
+      '--newline',
+    ], (progress) => {
+      if (onDownloadProgress) {
+        onDownloadProgress({
+          ...progress,
+          title: info.title,
+        });
+      }
+    });
+
+    return {
+      success: true,
+      title: info.title,
+      duration: info.duration,
+      filePath: outputPath,
+      url: url,
+    };
+  } catch (error) {
+    throw new Error(`Failed to download: ${error.message}`);
+  }
+}
+
+/**
+ * Download all videos from a playlist as MP3
+ */
+export async function downloadPlaylist(url, options = {}) {
+  const { outputDir = OUTPUT_DIR, onProgress, onVideoComplete, onDownloadProgress, forcePlaylist = false } = options;
+
+  // Ensure output directory exists
+  if (!fs.existsSync(outputDir)) {
+    fs.mkdirSync(outputDir, { recursive: true });
+  }
+
+  try {
+    // Get playlist info (force playlist mode if URL has list= param)
+    const info = await getInfo(url, forcePlaylist || hasPlaylistParam(url));
+
+    if (info._type !== 'playlist') {
+      // Single video, redirect to downloadVideo
+      const result = await downloadVideo(url, { ...options, onDownloadProgress });
+      return {
+        success: true,
+        playlistTitle: result.title,
+        videos: [result],
+        totalVideos: 1,
+      };
+    }
+
+    const results = [];
+    const entries = info.entries || [];
+
+    console.log(`Playlist: ${info.title} (${entries.length} videos)`);
+
+    for (let i = 0; i < entries.length; i++) {
+      const entry = entries[i];
+      const videoUrl = entry.url || `https://www.youtube.com/watch?v=${entry.id}`;
+
+      try {
+        if (onProgress) {
+          onProgress({ current: i + 1, total: entries.length, title: entry.title });
+        }
+
+        console.log(`[${i + 1}/${entries.length}] Downloading: ${entry.title}`);
+
+        // Wrap progress callback to include playlist context
+        const wrappedProgress = onDownloadProgress ? (progress) => {
+          onDownloadProgress({
+            ...progress,
+            videoIndex: i + 1,
+            totalVideos: entries.length,
+            playlistTitle: info.title,
+          });
+        } : undefined;
+
+        const result = await downloadVideo(videoUrl, { outputDir, onDownloadProgress: wrappedProgress });
+        results.push(result);
+
+        if (onVideoComplete) {
+          onVideoComplete(result);
+        }
+      } catch (error) {
+        console.error(`Failed to download ${entry.title}: ${error.message}`);
+        results.push({
+          success: false,
+          title: entry.title,
+          url: videoUrl,
+          error: error.message,
+        });
+      }
+    }
+
+    return {
+      success: true,
+      playlistTitle: info.title,
+      videos: results,
+      totalVideos: entries.length,
+      successCount: results.filter(r => r.success).length,
+      failCount: results.filter(r => !r.success).length,
+    };
+  } catch (error) {
+    throw new Error(`Failed to download playlist: ${error.message}`);
+  }
+}
+
+/**
+ * Smart download - detects if URL is video or playlist
+ */
+export async function download(url, options = {}) {
+  // If URL contains list= parameter, treat it as a playlist
+  const isPlaylistUrl = hasPlaylistParam(url);
+  const info = await getInfo(url, isPlaylistUrl);
+
+  if (info._type === 'playlist') {
+    return downloadPlaylist(url, { ...options, forcePlaylist: true });
+  } else {
+    const result = await downloadVideo(url, options);
+    return {
+      success: true,
+      playlistTitle: null,
+      videos: [result],
+      totalVideos: 1,
+      successCount: 1,
+      failCount: 0,
+    };
+  }
+}
diff --git a/start-server.bat b/start-server.bat
index 4a94129..e087a22 100644
--- a/start-server.bat
+++ b/start-server.bat
@@ -1,61 +1,61 @@
-@echo off
-REM Video to MP3 Transcriptor Server Starter
-REM This script starts the API server on port 8888
-
-echo ==========================================
-echo Video to MP3 Transcriptor API
-echo ==========================================
-echo.
-
-REM Check if node is installed
-where node >nul 2>nul
-if %ERRORLEVEL% NEQ 0 (
-    echo Error: Node.js is not installed
-    echo Please install Node.js from https://nodejs.org/
-    pause
-    exit /b 1
-)
-
-REM Check if npm is installed
-where npm >nul 2>nul
-if %ERRORLEVEL% NEQ 0 (
-    echo Error: npm is not installed
-    echo Please install npm
-    pause
-    exit /b 1
-)
-
-REM Check if .env file exists
-if not exist .env (
-    echo Warning: .env file not found
-    echo Creating .env file...
-    (
-        echo OPENAI_API_KEY=
-        echo PORT=8888
-        echo OUTPUT_DIR=./output
-    ) > .env
-    echo.
-    echo Please edit .env and add your OPENAI_API_KEY
-    echo.
-)
-
-REM Check if node_modules exists
-if not exist node_modules (
-    echo Installing dependencies...
-    call npm install
-    echo.
-)
-
-REM Kill any process using port 8888
-echo Checking port 8888...
-npx kill-port 8888 >nul 2>nul
-
-echo.
-echo Starting server on http://localhost:8888
-echo Press Ctrl+C to stop the server
-echo.
-echo ==========================================
-echo.
-
-REM Start the server
-call npm run server
+@echo off
+REM Video to MP3 Transcriptor Server Starter
+REM This script starts the API server on port 8888
+
+echo ==========================================
+echo Video to MP3 Transcriptor API
+echo ==========================================
+echo.
+
+REM Check if node is installed
+where node >nul 2>nul
+if %ERRORLEVEL% NEQ 0 (
+    echo Error: Node.js is not installed
+    echo Please install Node.js from https://nodejs.org/
+    pause
+    exit /b 1
+)
+
+REM Check if npm is installed
+where npm >nul 2>nul
+if %ERRORLEVEL% NEQ 0 (
+    echo Error: npm is not installed
+    echo Please install npm
+    pause
+    exit /b 1
+)
+
+REM Check if .env file exists
+if not exist .env (
+    echo Warning: .env file not found
+    echo Creating .env file...
+    (
+        echo OPENAI_API_KEY=
+        echo PORT=8888
+        echo OUTPUT_DIR=./output
+    ) > .env
+    echo.
+    echo Please edit .env and add your OPENAI_API_KEY
+    echo.
+)
+
+REM Check if node_modules exists
+if not exist node_modules (
+    echo Installing dependencies...
+    call npm install
+    echo.
+)
+
+REM Kill any process using port 8888
+echo Checking port 8888...
+npx kill-port 8888 >nul 2>nul
+
+echo.
+echo Starting server on http://localhost:8888
+echo Press Ctrl+C to stop the server
+echo.
+echo ==========================================
+echo.
+
+REM Start the server
+call npm run server
diff --git a/start-server.sh b/start-server.sh
index 523385a..1bf5605 100644
--- a/start-server.sh
+++ b/start-server.sh
@@ -1,58 +1,58 @@
-#!/bin/bash
-
-# Video to MP3 Transcriptor Server Starter
-# This script starts the API server on port 8888
-
-echo "=========================================="
-echo "Video to MP3 Transcriptor API"
-echo "=========================================="
-echo ""
-
-# Check if node is installed
-if ! command -v node &> /dev/null
-then
-    echo "Error: Node.js is not installed"
-    echo "Please install Node.js from https://nodejs.org/"
-    exit 1
-fi
-
-# Check if npm is installed
-if ! command -v npm &> /dev/null
-then
-    echo "Error: npm is not installed"
-    echo "Please install npm"
-    exit 1
-fi
-
-# Check if .env file exists
-if [ ! -f .env ]; then
-    echo "Warning: .env file not found"
-    echo "Creating .env file..."
-    echo "OPENAI_API_KEY=" > .env
-    echo "PORT=8888" >> .env
-    echo "OUTPUT_DIR=./output" >> .env
-    echo ""
-    echo "Please edit .env and add your OPENAI_API_KEY"
-    echo ""
-fi
-
-# Check if node_modules exists
-if [ ! -d "node_modules" ]; then
-    echo "Installing dependencies..."
-    npm install
-    echo ""
-fi
-
-# Kill any process using port 8888
-echo "Checking port 8888..."
-npx kill-port 8888 2>/dev/null
-
-echo ""
-echo "Starting server on http://localhost:8888"
-echo "Press Ctrl+C to stop the server"
-echo ""
-echo "=========================================="
-echo ""
-
-# Start the server
-npm run server
+#!/bin/bash
+
+# Video to MP3 Transcriptor Server Starter
+# This script starts the API server on port 8888
+
+echo "=========================================="
+echo "Video to MP3 Transcriptor API"
+echo "=========================================="
+echo ""
+
+# Check if node is installed
+if ! command -v node &> /dev/null
+then
+    echo "Error: Node.js is not installed"
+    echo "Please install Node.js from https://nodejs.org/"
+    exit 1
+fi
+
+# Check if npm is installed
+if ! command -v npm &> /dev/null
+then
+    echo "Error: npm is not installed"
+    echo "Please install npm"
+    exit 1
+fi
+
+# Check if .env file exists
+if [ ! -f .env ]; then
+    echo "Warning: .env file not found"
+    echo "Creating .env file..."
+    echo "OPENAI_API_KEY=" > .env
+    echo "PORT=8888" >> .env
+    echo "OUTPUT_DIR=./output" >> .env
+    echo ""
+    echo "Please edit .env and add your OPENAI_API_KEY"
+    echo ""
+fi
+
+# Check if node_modules exists
+if [ ! -d "node_modules" ]; then
+    echo "Installing dependencies..."
+    npm install
+    echo ""
+fi
+
+# Kill any process using port 8888
+echo "Checking port 8888..."
+npx kill-port 8888 2>/dev/null
+
+echo ""
+echo "Starting server on http://localhost:8888"
+echo "Press Ctrl+C to stop the server"
+echo ""
+echo "=========================================="
+echo ""
+
+# Start the server
+npm run server