#include <grove/ModuleLoader.h>
#include <grove/JsonDataNode.h>
#include <grove/IOFactory.h>

#include <spdlog/spdlog.h>
#include <spdlog/sinks/stdout_color_sinks.h>

#include <chrono>
#include <thread>
#include <csignal>
#include <filesystem>
#include <fstream>
#include <map>

namespace fs = std::filesystem;

// Global flag for clean shutdown
static volatile bool g_running = true;

void signalHandler(int signal) {
    spdlog::info("Signal {} recu, arret en cours...", signal);
    g_running = false;
}

// Simple file watcher for hot-reload
class FileWatcher {
public:
    void watch(const std::string& path) {
        if (fs::exists(path)) {
            m_lastModified[path] = fs::last_write_time(path);
        }
    }

    bool hasChanged(const std::string& path) {
        if (!fs::exists(path)) return false;

        auto currentTime = fs::last_write_time(path);
        auto it = m_lastModified.find(path);

        if (it == m_lastModified.end()) {
            m_lastModified[path] = currentTime;
            return false;
        }

        if (currentTime != it->second) {
            it->second = currentTime;
            return true;
        }
        return false;
    }

private:
    std::unordered_map<std::string, fs::file_time_type> m_lastModified;
};

// Load JSON config file
std::unique_ptr<grove::JsonDataNode> loadConfig(const std::string& path) {
    if (fs::exists(path)) {
        std::ifstream file(path);
        nlohmann::json j;
        file >> j;
        auto config = std::make_unique<grove::JsonDataNode>("config", j);
        spdlog::info("Config chargee: {}", path);
        return config;
    } else {
        spdlog::warn("Config non trouvee: {}, utilisation des defauts", path);
        return std::make_unique<grove::JsonDataNode>("config");
    }
}

// Module entry in our simple manager
struct ModuleEntry {
    std::string name;
    std::string configFile;
    std::string path;
    std::unique_ptr<grove::ModuleLoader> loader;
    std::unique_ptr<grove::IIO> io;
    grove::IModule* module = nullptr;
};

int main(int argc, char* argv[]) {
    // Setup logging
    auto console = spdlog::stdout_color_mt("MobileCommand");
    spdlog::set_default_logger(console);
    spdlog::set_level(spdlog::level::debug);
    spdlog::set_pattern("[%H:%M:%S.%e] [%n] [%^%l%$] %v");

    spdlog::info("========================================");
    spdlog::info("  MOBILE COMMAND");
    spdlog::info("  Survival Management / Base Building");
    spdlog::info("  Powered by GroveEngine");
    spdlog::info("========================================");

    // Signal handling
    std::signal(SIGINT, signalHandler);
    std::signal(SIGTERM, signalHandler);

    // Paths - try ./modules/ first, fallback to ./build/modules/
    std::string modulesDir = "./modules/";
    if (!fs::exists(modulesDir) || fs::is_empty(modulesDir)) {
        if (fs::exists("./build/modules/")) {
            modulesDir = "./build/modules/";
            spdlog::info("Using modules from: {}", modulesDir);
        }
    }
    const std::string configDir = "./config/";

    // =========================================================================
    // Hot-Reloadable Modules
    // =========================================================================
    std::map<std::string, ModuleEntry> modules;
    FileWatcher watcher;

    // Liste des modules a charger
    std::vector<std::pair<std::string, std::string>> moduleList = {
        {"GameModule", "game.json"},
    };

    // Charger les modules
    for (const auto& [moduleName, configFile] : moduleList) {
        std::string modulePath = modulesDir + "lib" + moduleName + ".so";

        if (!fs::exists(modulePath)) {
            spdlog::warn("{} non trouve: {}", moduleName, modulePath);
            continue;
        }

        ModuleEntry entry;
        entry.name = moduleName;
        entry.configFile = configFile;
        entry.path = modulePath;
        entry.loader = std::make_unique<grove::ModuleLoader>();
        entry.io = grove::IOFactory::create("intra", moduleName);

        auto modulePtr = entry.loader->load(modulePath, moduleName);
        if (!modulePtr) {
            spdlog::error("Echec du chargement: {}", moduleName);
            continue;
        }

        // Configure
        auto config = loadConfig(configDir + configFile);
        modulePtr->setConfiguration(*config, entry.io.get(), nullptr);

        entry.module = modulePtr.release();
        watcher.watch(modulePath);

        spdlog::info("{} charge et configure", moduleName);
        modules[moduleName] = std::move(entry);
    }

    if (modules.empty()) {
        spdlog::warn("Aucun module charge! Build les modules: cmake --build build --target modules");
        spdlog::info("Demarrage sans modules (mode minimal)...");
    }

    // =========================================================================
    // Main Loop
    // =========================================================================
    spdlog::info("Demarrage de la boucle principale (Ctrl+C pour quitter)");

    using Clock = std::chrono::high_resolution_clock;
    auto startTime = Clock::now();
    auto lastFrame = Clock::now();
    const auto targetFrameTime = std::chrono::milliseconds(100); // 10 Hz

    grove::JsonDataNode frameInput("frame");
    uint64_t frameCount = 0;

    while (g_running) {
        auto frameStart = Clock::now();

        // Calculate times
        auto deltaTime = std::chrono::duration<float>(frameStart - lastFrame).count();
        auto gameTime = std::chrono::duration<float>(frameStart - startTime).count();
        lastFrame = frameStart;

        // Prepare frame input
        frameInput.setDouble("deltaTime", deltaTime);
        frameInput.setInt("frameCount", frameCount);
        frameInput.setDouble("gameTime", gameTime);

        // =====================================================================
        // Hot-Reload Check (every 10 frames = ~1 second)
        // =====================================================================
        if (frameCount % 10 == 0) {
            for (auto& [name, entry] : modules) {
                if (watcher.hasChanged(entry.path)) {
                    spdlog::info("Modification detectee: {}, hot-reload...", name);

                    // Get state before reload
                    std::unique_ptr<grove::IDataNode> state;
                    if (entry.module) {
                        state = entry.module->getState();
                    }

                    // Reload
                    auto reloaded = entry.loader->load(entry.path, name, true);
                    if (reloaded) {
                        auto config = loadConfig(configDir + entry.configFile);
                        reloaded->setConfiguration(*config, entry.io.get(), nullptr);

                        if (state) {
                            reloaded->setState(*state);
                        }

                        entry.module = reloaded.release();
                        spdlog::info("{} recharge avec succes!", name);
                    }
                }
            }
        }

        // =====================================================================
        // Process Modules (hot-reloadable)
        // =====================================================================
        for (auto& [name, entry] : modules) {
            if (entry.module) {
                entry.module->process(frameInput);
            }
        }

        // =====================================================================
        // Frame timing
        // =====================================================================
        frameCount++;

        auto frameEnd = Clock::now();
        auto frameDuration = frameEnd - frameStart;

        if (frameDuration < targetFrameTime) {
            std::this_thread::sleep_for(targetFrameTime - frameDuration);
        }

        // Status log every 30 seconds
        if (frameCount % 300 == 0) {
            int minutes = static_cast<int>(gameTime / 60.0f);
            int seconds = static_cast<int>(gameTime) % 60;
            spdlog::debug("Session: {}m{}s, {} modules actifs",
                         minutes, seconds, modules.size());
        }
    }

    // =========================================================================
    // Shutdown
    // =========================================================================
    spdlog::info("Arret en cours...");

    // Shutdown modules
    for (auto& [name, entry] : modules) {
        if (entry.module) {
            entry.module->shutdown();
            spdlog::info("{} arrete", name);
        }
    }

    spdlog::info("A bientot!");
    return 0;
}