#include "cmd_dispatcher.h"
#include "protocol.h"
#include "uart_handler.h"

#include "esp_system.h"
#include "esp_chip_info.h"
#include "esp_timer.h"
#include "esp_log.h"
#include "esp_mac.h"
#include "esp_bt.h"
#include "cJSON.h"

#include <string.h>

#define FW_VERSION "0.1.0"

static const char *TAG = "dispatch";

typedef void (*cmd_handler_t)(const char *id, cJSON *params);

typedef struct {
    const char *name;
    cmd_handler_t handler;
} cmd_entry_t;

/* Forward declarations for handlers in other modules */
extern void bt_classic_register_commands(void);
extern void bt_ble_register_commands(void);
extern void personas_register_commands(void);

/* --- System command handlers --- */

static void handle_ping(const char *id, cJSON *params)
{
    (void)params;
    cJSON *data = cJSON_CreateObject();
    cJSON_AddBoolToObject(data, "pong", cJSON_True);
    uart_send_response(id, STATUS_OK, data);
}

static void handle_reset(const char *id, cJSON *params)
{
    (void)params;
    uart_send_response(id, STATUS_OK, NULL);
    vTaskDelay(pdMS_TO_TICKS(100));  /* let the response flush */
    esp_restart();
}

static void handle_get_info(const char *id, cJSON *params)
{
    (void)params;

    esp_chip_info_t chip;
    esp_chip_info(&chip);

    const char *model;
    switch (chip.model) {
        case CHIP_ESP32:   model = "ESP32";    break;
        case CHIP_ESP32S2: model = "ESP32-S2"; break;
        case CHIP_ESP32S3: model = "ESP32-S3"; break;
        case CHIP_ESP32C3: model = "ESP32-C3"; break;
        case CHIP_ESP32H2: model = "ESP32-H2"; break;
        default:           model = "unknown";  break;
    }

    /* Decode feature flags */
    cJSON *features = cJSON_CreateArray();
    if (chip.features & CHIP_FEATURE_WIFI_BGN) cJSON_AddItemToArray(features, cJSON_CreateString("wifi"));
    if (chip.features & CHIP_FEATURE_BT)       cJSON_AddItemToArray(features, cJSON_CreateString("bt"));
    if (chip.features & CHIP_FEATURE_BLE)      cJSON_AddItemToArray(features, cJSON_CreateString("ble"));

    /* BT MAC address */
    uint8_t mac[6];
    esp_read_mac(mac, ESP_MAC_BT);
    char mac_str[18];
    snprintf(mac_str, sizeof(mac_str), "%02X:%02X:%02X:%02X:%02X:%02X",
             mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);

    cJSON *data = cJSON_CreateObject();
    cJSON_AddStringToObject(data, "chip_model", model);
    cJSON_AddItemToObject(data, "features", features);
    cJSON_AddNumberToObject(data, "revision", chip.revision);
    cJSON_AddNumberToObject(data, "cores", chip.cores);
    cJSON_AddStringToObject(data, "fw_version", FW_VERSION);
    cJSON_AddNumberToObject(data, "free_heap", (double)esp_get_free_heap_size());
    cJSON_AddStringToObject(data, "bt_mac", mac_str);

    uart_send_response(id, STATUS_OK, data);
}

static void handle_get_status(const char *id, cJSON *params)
{
    (void)params;

    int64_t uptime_ms = esp_timer_get_time() / 1000;

    cJSON *data = cJSON_CreateObject();
    cJSON_AddNumberToObject(data, "uptime_ms", (double)uptime_ms);
    cJSON_AddNumberToObject(data, "free_heap", (double)esp_get_free_heap_size());
    cJSON_AddBoolToObject(data, "bt_enabled", cJSON_False);
    cJSON_AddBoolToObject(data, "ble_enabled", cJSON_False);

    uart_send_response(id, STATUS_OK, data);
}

/* --- Command table --- */

static const cmd_entry_t cmd_table[] = {
    { CMD_PING,       handle_ping       },
    { CMD_RESET,      handle_reset      },
    { CMD_GET_INFO,   handle_get_info   },
    { CMD_GET_STATUS, handle_get_status },
    { NULL, NULL }  /* sentinel */
};

void cmd_dispatcher_init(void)
{
    ESP_LOGI(TAG, "command dispatcher ready");

    /* Future: these will register their own handlers into the table */
    /* bt_classic_register_commands(); */
    /* bt_ble_register_commands(); */
    /* personas_register_commands(); */
}

void cmd_dispatch(const char *id, const char *cmd, cJSON *params)
{
    for (const cmd_entry_t *entry = cmd_table; entry->name != NULL; entry++) {
        if (strcmp(entry->name, cmd) == 0) {
            entry->handler(id, params);
            return;
        }
    }

    ESP_LOGW(TAG, "unknown command: %s", cmd);
    cJSON *err = cJSON_CreateObject();
    cJSON_AddStringToObject(err, "error", "unknown_command");
    cJSON_AddStringToObject(err, "cmd", cmd);
    uart_send_response(id, STATUS_ERROR, err);
}