/**
 * @file main.c
 * @brief ESP32-S3 GNUBoy Emulator - Main Entry Point
 * 
 * LEGO GameBoy Emulator Project
 * Hardware: Waveshare ESP32-S3-Touch-LCD-2
 * 
 * Features:
 * - GameBoy/GameBoy Color emulation
 * - NFC ROM selection
 * - Potentiometer volume/brightness control
 * - Link Cable 2-player support
 * - SD Card ROM loading
 */

#include <stdio.h>
#include <string.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "esp_system.h"
#include "esp_log.h"
#include "esp_err.h"
#include "nvs_flash.h"
#include "esp_psram.h"

#include "hardware_config.h"

// Component includes (will be created)
// #include "st7789.h"
// #include "nfc_manager.h"
// #include "link_cable.h"
// #include "potentiometer_manager.h"
// #include "gnuboy.h"

static const char *TAG = "MAIN";

/**
 * @brief Callback for potentiometer changes
 */
static void poti_change_handler(uint8_t volume, uint8_t brightness)
{
    ESP_LOGI(TAG, "Potentiometer changed: Volume=%d%%, Brightness=%d%%", 
             volume, brightness);
    
    // TODO: Set audio volume when audio is implemented
    // audio_set_volume(volume);
}

/**
 * @brief Initialize NVS (Non-Volatile Storage)
 */
static void init_nvs(void)
{
    ESP_LOGI(TAG, "Initializing NVS...");
    
    esp_err_t ret = nvs_flash_init();
    if (ret == ESP_ERR_NVS_NO_FREE_PAGES || ret == ESP_ERR_NVS_NEW_VERSION_FOUND) {
        ESP_LOGW(TAG, "NVS partition was truncated, erasing...");
        ESP_ERROR_CHECK(nvs_flash_erase());
        ret = nvs_flash_init();
    }
    ESP_ERROR_CHECK(ret);
    
    ESP_LOGI(TAG, "✓ NVS initialized");
}

/**
 * @brief Initialize PSRAM
 */
static void init_psram(void)
{
    ESP_LOGI(TAG, "Checking PSRAM...");
    
    if (esp_psram_is_initialized()) {
        size_t psram_size = esp_psram_get_size();
        ESP_LOGI(TAG, "✓ PSRAM initialized: %d MB", psram_size / (1024 * 1024));
    } else {
        ESP_LOGE(TAG, "✗ PSRAM not available!");
        ESP_LOGE(TAG, "  Make sure PSRAM is enabled in sdkconfig!");
    }
}

/**
 * @brief Print system information
 */
static void print_system_info(void)
{
    ESP_LOGI(TAG, "");
    ESP_LOGI(TAG, "╔════════════════════════════════════════════════════════╗");
    ESP_LOGI(TAG, "║                                                        ║");
    ESP_LOGI(TAG, "║       ESP32-S3 GNUBoy LEGO GameBoy Emulator           ║");
    ESP_LOGI(TAG, "║                                                        ║");
    ESP_LOGI(TAG, "╚════════════════════════════════════════════════════════╝");
    ESP_LOGI(TAG, "");
    ESP_LOGI(TAG, "Hardware: Waveshare ESP32-S3-Touch-LCD-2");
    ESP_LOGI(TAG, "Display:  ST7789 2.0\" 240x320");
    ESP_LOGI(TAG, "Flash:    %d MB", spi_flash_get_chip_size() / (1024 * 1024));
    
    if (esp_psram_is_initialized()) {
        ESP_LOGI(TAG, "PSRAM:    %d MB", esp_psram_get_size() / (1024 * 1024));
    }
    
    ESP_LOGI(TAG, "");
    ESP_LOGI(TAG, "Features:");
    ESP_LOGI(TAG, "  ✓ GameBoy / GameBoy Color emulation");
    ESP_LOGI(TAG, "  ✓ NFC ROM selection");
    ESP_LOGI(TAG, "  ✓ Potentiometer controls");
    ESP_LOGI(TAG, "  ✓ Link Cable 2-player");
    ESP_LOGI(TAG, "  ✓ SD Card ROM loading");
    ESP_LOGI(TAG, "");
}

/**
 * @brief Initialize hardware components
 */
static void init_hardware(void)
{
    ESP_LOGI(TAG, "Initializing hardware components...");
    
    // TODO: Initialize display (ST7789)
    // st7789_init();
    ESP_LOGI(TAG, "  [ ] Display (ST7789) - TODO");
    
    // TODO: Initialize buttons
    // buttons_init();
    ESP_LOGI(TAG, "  [ ] Buttons - TODO");
    
    // TODO: Initialize audio (I2S)
    // audio_init();
    ESP_LOGI(TAG, "  [ ] Audio (I2S) - TODO");
    
    // TODO: Initialize SD Card
    // sd_card_init();
    ESP_LOGI(TAG, "  [ ] SD Card - TODO");
    
    // TODO: Initialize NFC
    // nfc_manager_init();
    ESP_LOGI(TAG, "  [ ] NFC Reader - TODO");
    
    // TODO: Initialize Link Cable
    // link_cable_init();
    ESP_LOGI(TAG, "  [ ] Link Cable - TODO");
    
    // TODO: Initialize Potentiometers
    // poti_manager_init();
    // poti_manager_start(poti_change_handler);
    ESP_LOGI(TAG, "  [ ] Potentiometers - TODO");
    
    ESP_LOGI(TAG, "✓ Hardware initialization complete");
}

/**
 * @brief Main application entry point
 */
void app_main(void)
{
    // Print welcome banner
    print_system_info();
    
    // Initialize core systems
    init_nvs();
    init_psram();
    
    // Initialize hardware peripherals
    init_hardware();
    
    ESP_LOGI(TAG, "");
    ESP_LOGI(TAG, "════════════════════════════════════════════════════════");
    ESP_LOGI(TAG, "System initialization complete!");
    ESP_LOGI(TAG, "════════════════════════════════════════════════════════");
    ESP_LOGI(TAG, "");
    
    // TODO: Start emulator
    ESP_LOGI(TAG, "Starting GNUBoy emulator...");
    ESP_LOGI(TAG, "  (GNUBoy core not yet integrated)");
    
    // Main loop
    ESP_LOGI(TAG, "Entering main loop...");
    while (1) {
        // TODO: Run emulator main loop
        // gnuboy_run_frame();
        
        vTaskDelay(pdMS_TO_TICKS(100));
    }
}