#include <stdio.h>
#include <inttypes.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "esp_system.h"
#include "esp_chip_info.h"
#include "esp_flash.h"
#include "esp_log.h"
#include "esp_timer.h"
#include "driver/gpio.h"

/* OS Subsystems */
#include "os_event.h"
#include "os_status.h"
#include "os_gfx.h"
#include "os_input.h"
#include "os_app.h"
#include "os_cli.h"
#include "sys_wifi.h"
#include "sys_uart.h"
#include "apps.h"

static const char *TAG = "MICRO_OS";

#define PIN_LED_USER        GPIO_NUM_8
#define PIN_BUTTON_BOOT     GPIO_NUM_9
#define UI_REFRESH_HZ       20
#define UI_FRAME_MS         (1000 / UI_REFRESH_HZ)

/* Task: Onboard LED Heartbeat */
static void led_heartbeat_task(void *pvParameters)
{
    gpio_config_t io_conf = {
        .pin_bit_mask = (1ULL << PIN_LED_USER),
        .mode = GPIO_MODE_OUTPUT,
        .pull_up_en = GPIO_PULLUP_DISABLE,
        .pull_down_en = GPIO_PULLDOWN_DISABLE,
        .intr_type = GPIO_INTR_DISABLE,
    };
    gpio_config(&io_conf);

    while (1) {
        gpio_set_level(PIN_LED_USER, 1);
        vTaskDelay(pdMS_TO_TICKS(60));
        gpio_set_level(PIN_LED_USER, 0);
        vTaskDelay(pdMS_TO_TICKS(100));
        gpio_set_level(PIN_LED_USER, 1);
        vTaskDelay(pdMS_TO_TICKS(60));
        gpio_set_level(PIN_LED_USER, 0);
        vTaskDelay(pdMS_TO_TICKS(800));
    }
}

/* Callback: Forward button gestures to App Manager */
static void on_input_event(input_action_t action, void *user_arg)
{
    sys_app_dispatch_input(action);
}

/* Task: OS Display & UI Compositor Loop */
static void os_ui_task(void *pvParameters)
{
    ESP_LOGI(TAG, "Starting UI compositor loop @ %d FPS", UI_REFRESH_HZ);
    uint32_t last_time_ms = (uint32_t)(esp_timer_get_time() / 1000ULL);

    while (1) {
        uint32_t now_ms = (uint32_t)(esp_timer_get_time() / 1000ULL);
        uint32_t delta_ms = now_ms - last_time_ms;
        last_time_ms = now_ms;

        sys_status_update();
        sys_gfx_clear();
        sys_app_update(delta_ms);
        sys_gfx_render_toast_if_active();
        sys_gfx_flush();

        vTaskDelay(pdMS_TO_TICKS(UI_FRAME_MS));
    }
}

void app_main(void)
{
    ESP_LOGI(TAG, "=============================================");
    ESP_LOGI(TAG, "  Booting ABrobot ESP32-C3 Micro-OS v1.0.0   ");
    ESP_LOGI(TAG, "=============================================");

    // 1. Core Services & Telemetry
    sys_event_init();
    sys_status_init();
    esp_err_t err;

    // 1b. Wi-Fi and provisioning services
    err = sys_wifi_init();
    if (err != ESP_OK) {
        ESP_LOGE(TAG, "Failed to initialize Wi-Fi subsystem: %s", esp_err_to_name(err));
    }

    // 1c. Hardware UART Subsystem (TX: GPIO 21, RX: GPIO 20)
    err = sys_uart_init(115200);
    if (err != ESP_OK) {
        ESP_LOGE(TAG, "Failed to initialize UART subsystem: %s", esp_err_to_name(err));
    }

    // 2. Display & Graphics Subsystem
    err = sys_gfx_init();
    if (err != ESP_OK) {
        ESP_LOGE(TAG, "Failed to initialize graphics subsystem: %s", esp_err_to_name(err));
    }

    // 3. Button & Gesture Engine
    sys_input_init(PIN_BUTTON_BOOT);
    sys_input_register_handler(on_input_event, NULL);

    // 4. Application Framework & Registry
    sys_app_init();
    sys_app_register(&g_app_clock);
    sys_app_register(&g_app_sysmon);
    sys_app_register(&g_app_serial);
    sys_app_register(&g_app_game);
    sys_app_register(&g_app_settings);

    // Launch default startup app
    sys_app_launch_by_id("clock");

    // 5. Interactive USB Console Shell
    sys_cli_init();

    // 6. Launch OS Tasks
    xTaskCreate(led_heartbeat_task, "led_hb_task", 2048, NULL, 5, NULL);
    xTaskCreate(os_ui_task, "ui_task", 4096, NULL, 10, NULL);

    ESP_LOGI(TAG, "Micro-OS initialized and running.");
}