warfactoryracine/modules/economy/src/EconomyModule.cpp

#include "../shared/ModuleBase.h"
#include <iostream>
#include <map>
#include <cmath>

using json = nlohmann::json;

namespace warfactory {

/**
 * @brief Economy Module - Pure market simulation logic
 *
 * Handles supply/demand, pricing, trading
 * Claude Code works ONLY on this file (~200-300 lines max)
 */
class EconomyModule : public ModuleBase {
private:
    struct MarketData {
        double price = 1.0;
        double supply = 0.0;
        double demand = 0.0;
        double base_price = 1.0;
        std::string trend = "stable";
    };

    std::map<std::string, MarketData> markets;
    double inflation_rate = 0.02;
    int simulation_tick = 0;

public:
    EconomyModule() : ModuleBase("Economy") {}

    json process(const json& input) override {
        ensureInitialized();

        std::string type = getField<std::string>(input, "type");

        if (type == "market_update") {
            return handleMarketUpdate(input);
        }
        else if (type == "trade") {
            return handleTrade(input);
        }
        else if (type == "get_prices") {
            return getPrices();
        }
        else if (type == "simulate_tick") {
            return simulateTick();
        }
        else if (type == "status") {
            return getStatus();
        }

        return {{"error", "Unknown command type: " + type}};
    }

protected:
    void onInitialize(const json& config) override {
        // Initialize base markets
        if (config.contains("markets")) {
            auto market_config = config["markets"];
            for (auto& [item, data] : market_config.items()) {
                MarketData market;
                market.base_price = getField<double>(data, "base_price", 1.0);
                market.price = market.base_price;
                market.supply = getField<double>(data, "initial_supply", 100.0);
                market.demand = getField<double>(data, "initial_demand", 100.0);
                markets[item] = market;
            }
        }

        // Initialize default markets if none provided
        if (markets.empty()) {
            loadDefaultMarkets();
        }

        inflation_rate = getField<double>(module_config, "inflation_rate", 0.02);

        std::cout << "💰 Economy Module initialized with "
                  << markets.size() << " markets" << std::endl;
    }

private:
    json handleMarketUpdate(const json& input) {
        std::string item = getField<std::string>(input, "item");

        if (markets.find(item) == markets.end()) {
            // Create new market
            markets[item] = MarketData{};
        }

        auto& market = markets[item];

        if (input.contains("supply")) {
            market.supply = getField<double>(input, "supply");
        }
        if (input.contains("demand")) {
            market.demand = getField<double>(input, "demand");
        }

        // Recalculate price based on supply/demand
        updatePrice(item);

        return {
            {"status", "updated"},
            {"item", item},
            {"new_price", market.price},
            {"supply", market.supply},
            {"demand", market.demand},
            {"trend", market.trend}
        };
    }

    json handleTrade(const json& input) {
        std::string action = getField<std::string>(input, "action");
        std::string item = getField<std::string>(input, "item");
        double quantity = getField<double>(input, "quantity");

        if (markets.find(item) == markets.end()) {
            return {{"error", "Market not found for item: " + item}};
        }

        auto& market = markets[item];
        double current_price = market.price;

        if (action == "buy") {
            double max_price = getField<double>(input, "max_price", 999999.0);

            if (current_price > max_price) {
                return {
                    {"status", "trade_rejected"},
                    {"reason", "price_too_high"},
                    {"current_price", current_price},
                    {"max_price", max_price}
                };
            }

            // Execute buy order
            market.demand += quantity;
            market.supply = std::max(0.0, market.supply - quantity);
            updatePrice(item);

            return {
                {"status", "trade_executed"},
                {"action", "buy"},
                {"item", item},
                {"quantity", quantity},
                {"price", current_price},
                {"total_cost", quantity * current_price}
            };
        }
        else if (action == "sell") {
            double min_price = getField<double>(input, "min_price", 0.0);

            if (current_price < min_price) {
                return {
                    {"status", "trade_rejected"},
                    {"reason", "price_too_low"},
                    {"current_price", current_price},
                    {"min_price", min_price}
                };
            }

            // Execute sell order
            market.supply += quantity;
            market.demand = std::max(0.0, market.demand - quantity);
            updatePrice(item);

            return {
                {"status", "trade_executed"},
                {"action", "sell"},
                {"item", item},
                {"quantity", quantity},
                {"price", current_price},
                {"total_revenue", quantity * current_price}
            };
        }

        return {{"error", "Invalid trade action: " + action}};
    }

    json getPrices() {
        json prices = json::object();

        for (const auto& [item, market] : markets) {
            prices[item] = {
                {"price", market.price},
                {"trend", market.trend},
                {"supply", market.supply},
                {"demand", market.demand}
            };
        }

        return {
            {"market_data", prices},
            {"inflation_rate", inflation_rate},
            {"simulation_tick", simulation_tick}
        };
    }

    json simulateTick() {
        simulation_tick++;

        // Simulate market fluctuations
        for (auto& [item, market] : markets) {
            // Add some random market movement
            double volatility = 0.05; // 5% volatility
            double random_factor = 1.0 + (rand() / (double)RAND_MAX - 0.5) * volatility;

            // Natural decay towards equilibrium
            double equilibrium_ratio = market.demand / std::max(market.supply, 1.0);
            market.price = market.base_price * equilibrium_ratio * random_factor;

            // Apply inflation
            market.base_price *= (1.0 + inflation_rate / 100.0);

            updateTrend(item);
        }

        return {
            {"status", "tick_processed"},
            {"simulation_tick", simulation_tick},
            {"markets_updated", markets.size()}
        };
    }

    json getStatus() {
        return {
            {"module", "Economy"},
            {"markets_count", markets.size()},
            {"simulation_tick", simulation_tick},
            {"inflation_rate", inflation_rate}
        };
    }

    void updatePrice(const std::string& item) {
        auto& market = markets[item];

        if (market.supply <= 0) {
            market.price = market.base_price * 2.0; // Scarcity premium
        } else {
            double ratio = market.demand / market.supply;
            market.price = market.base_price * std::max(0.1, ratio);
        }

        updateTrend(item);
    }

    void updateTrend(const std::string& item) {
        auto& market = markets[item];
        double ratio = market.demand / std::max(market.supply, 1.0);

        if (ratio > 1.2) {
            market.trend = "rising";
        } else if (ratio < 0.8) {
            market.trend = "falling";
        } else {
            market.trend = "stable";
        }
    }

    void loadDefaultMarkets() {
        markets["iron_ore"] = {1.0, 100.0, 100.0, 1.0, "stable"};
        markets["copper_ore"] = {1.2, 80.0, 90.0, 1.2, "stable"};
        markets["coal"] = {0.8, 120.0, 100.0, 0.8, "stable"};
        markets["steel_plate"] = {5.0, 50.0, 60.0, 5.0, "stable"};
        markets["copper_wire"] = {2.0, 70.0, 75.0, 2.0, "stable"};
        markets["circuit"] = {15.0, 20.0, 25.0, 15.0, "stable"};
    }
};

} // namespace warfactory

// C-style export functions for dynamic loading
extern "C" {
    warfactory::IModule* createModule() {
        return new warfactory::EconomyModule();
    }

    void destroyModule(warfactory::IModule* module) {
        delete module;
    }

    const char* getModuleName() {
        return "Economy";
    }
}