#include <stdio.h>

#define TAG "CAM"
#include "esp_camera.h"
#define PWDN_GPIO_NUM -1
#define RESET_GPIO_NUM -1
#define XCLK_GPIO_NUM 15
#define SIOD_GPIO_NUM 4
#define SIOC_GPIO_NUM 5

#define Y2_GPIO_NUM 11
#define Y3_GPIO_NUM 9
#define Y4_GPIO_NUM 8
#define Y5_GPIO_NUM 10
#define Y6_GPIO_NUM 12
#define Y7_GPIO_NUM 18
#define Y8_GPIO_NUM 17
#define Y9_GPIO_NUM 16

#define VSYNC_GPIO_NUM 6
#define HREF_GPIO_NUM 7
#define PCLK_GPIO_NUM 13

#define WIFI_IF WIFI_IF_AP

#define MAX_PAYLOAD_SIZE 1400

#include "esp_event.h"
#include "esp_system.h"
#include "esp_event.h"
#include "esp_timer.h"
#include "esp_wifi.h"
#include "esp_log.h"
#include "esp_mac.h"
#include "nvs_flash.h"
#include "string.h"

#include "lipton/cci.h"
#include "lipton/vospi.h"
#include "lipton/lepton_system.h"
#include "lipton/lepton_utilities.h"

// Number of consecutive VoSPI resynchronization attempts before attempting to reset
#define LEP_SYNC_FAIL_FAULT_LIMIT 10

// Reset fail delay before attempting a re-init (seconds)
#define LEP_RESET_FAIL_RETRY_SECS 5

//
// Code start
//
int vsync_count = 0;
int sync_fail_count = 0;
int reset_fail_count = 0;
int64_t vsyncDetectedUsec;

esp_err_t tx_with_retry(wifi_interface_t iface, const void *buffer, int len, bool en_sys_seq)
{
    for (int i = 0; i < 160; i++)
    {
        esp_err_t err = esp_wifi_80211_tx(iface, buffer, len, en_sys_seq);
        if (err == ESP_OK)
            return ESP_OK;
        if (err != ESP_ERR_NO_MEM)
            return err;
        // No delay, retry immediately
    }
    return ESP_ERR_NO_MEM;
}

static camera_config_t camera_config = {
    .pin_pwdn = PWDN_GPIO_NUM,
    .pin_reset = RESET_GPIO_NUM,
    .pin_xclk = XCLK_GPIO_NUM,
    // .pin_sccb_sda = SIOD_GPIO_NUM,
    // .pin_sccb_scl = SIOC_GPIO_NUM,
    .pin_sccb_sda = -1,
    .pin_sccb_scl = -1,
    .sccb_i2c_port = I2C_MASTER_NUM,

    .pin_d7 = Y9_GPIO_NUM,
    .pin_d6 = Y8_GPIO_NUM,
    .pin_d5 = Y7_GPIO_NUM,
    .pin_d4 = Y6_GPIO_NUM,
    .pin_d3 = Y5_GPIO_NUM,
    .pin_d2 = Y4_GPIO_NUM,
    .pin_d1 = Y3_GPIO_NUM,
    .pin_d0 = Y2_GPIO_NUM,
    .pin_vsync = VSYNC_GPIO_NUM,
    .pin_href = HREF_GPIO_NUM,
    .pin_pclk = PCLK_GPIO_NUM,

    .xclk_freq_hz = 20000000, // EXPERIMENTAL: Set to 16MHz on ESP32-S2 or ESP32-S3 to enable EDMA mode
    .ledc_timer = LEDC_TIMER_0,
    .ledc_channel = LEDC_CHANNEL_0,

    .pixel_format = PIXFORMAT_JPEG, // YUV422,GRAYSCALE,RGB565,JPEG
    .frame_size = FRAMESIZE_UXGA,   // QQVGA-UXGA, For ESP32, do not use sizes above QVGA when not JPEG. The performance of the ESP32-S series has improved a lot, but JPEG mode always gives better frame rates.+
    //.frame_size = FRAMESIZE_128X128, // QQVGA-UXGA, For ESP32, do not use sizes above QVGA when not JPEG. The performance of the ESP32-S series has improved a lot, but JPEG mode always gives better frame rates.

    .jpeg_quality = 12, // 0-63, for OV series camera sensors, lower number means higher quality
    .fb_count = 1,      // When jpeg mode is used, if fb_count more than one, the driver will work in continuous mode.
    //.fb_location = CAMERA_FB_IN_PSRAM,
    .fb_location = CAMERA_FB_IN_PSRAM,
    .grab_mode = CAMERA_GRAB_LATEST // CAMERA_GRAB_LATEST. Sets when buffers should be filled
};

esp_err_t esp_wifi_80211_tx(wifi_interface_t ifx, const void *buffer, int len, bool en_sys_seq);

uint16_t calculate_checksum(uint8_t *data, size_t len)
{
    uint16_t checksum = 0;
    for (size_t i = 0; i < len; i++)
    {
        checksum ^= data[i]; // Simple XOR-based checksum
    }
    return checksum;
}

void send_data_frame(uint8_t type, uint8_t *data, size_t len)
{
    uint8_t mac_addr[6];
    if (esp_wifi_get_mac(WIFI_IF_AP, mac_addr) != ESP_OK)
    {
        ESP_LOGE(TAG, "Failed to get MAC address");
        return;
    }

    uint8_t header[] = {
        0x08, 0x02, 0x00, 0x00,
        0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
        0x10, 0x00};
    memcpy(&header[10], mac_addr, 6);
    memcpy(&header[16], mac_addr, 6);

    size_t max_chunk_size = MAX_PAYLOAD_SIZE - (11 + 2);
    size_t total_chunks = (len + max_chunk_size - 1) / max_chunk_size;

    for (uint16_t seq = 0; seq < total_chunks; seq++)
    {
        size_t offset = seq * max_chunk_size;
        size_t chunk_size = (len - offset > max_chunk_size) ? max_chunk_size : (len - offset);

        uint8_t *raw_frame = malloc(11 + chunk_size + 2);
        uint8_t *full_packet = malloc(sizeof(header) + 11 + chunk_size + 2);
        if (!raw_frame || !full_packet)
        {
            ESP_LOGE(TAG, "Memory allocation failed!");
            free(raw_frame);
            free(full_packet);
            return;
        }

        raw_frame[0] = type;
        raw_frame[1] = seq >> 8;
        raw_frame[2] = seq & 0xFF;
        raw_frame[3] = total_chunks >> 8;
        raw_frame[4] = total_chunks & 0xFF;
        raw_frame[5] = 'P';
        raw_frame[6] = 'l';
        raw_frame[7] = 'e';
        raw_frame[8] = 'c';
        raw_frame[9] = 'y';
        raw_frame[10] = 'C';

        memcpy(raw_frame + 11, data + offset, chunk_size);
        uint16_t checksum = calculate_checksum(raw_frame, 11 + chunk_size);
        raw_frame[11 + chunk_size] = checksum >> 8;
        raw_frame[12 + chunk_size] = checksum & 0xFF;

        memcpy(full_packet, header, sizeof(header));
        memcpy(full_packet + sizeof(header), raw_frame, 11 + chunk_size + 2);

        esp_err_t ret = tx_with_retry(WIFI_IF, full_packet, sizeof(header) + 11 + chunk_size + 2, true);

        if (ret == ESP_OK)
        {
            ESP_LOGI(TAG, "Sent chunk %d/%d, size: %d bytes", seq + 1, total_chunks, chunk_size);
        }
        else
        {
            ESP_LOGE(TAG, "Failed to send chunk %d, %s", seq, esp_err_to_name(ret));
        }

        free(raw_frame);
        free(full_packet);
        vTaskDelay(50 / portTICK_PERIOD_MS);
    }
}

esp_err_t camera_init()
{
    // initialize the camera
    esp_err_t err = esp_camera_init(&camera_config);
    if (err != ESP_OK)
    {
        ESP_LOGE(TAG, "Camera Init Failed");
        return err;
    }

    return ESP_OK;
}

typedef struct
{
    bool isVisible;
    size_t len;
    size_t width;
    size_t height;
    pixformat_t format;
    struct timeval timestamp;
} PreData;

esp_err_t camera_capture()
{
    ESP_LOGI(TAG, "Pregrab");
    camera_fb_t *fb = esp_camera_fb_get();
    ESP_LOGI(TAG, "Postgrab");
    if (!fb)
    {
        ESP_LOGE(TAG, "Camera Capture Failed");
        return ESP_FAIL;
    }

    const size_t headerSize = sizeof(PreData);
    const size_t totalSize = fb->len + headerSize;
    uint8_t *dataOut = malloc(totalSize);
    if (!dataOut)
    {
        ESP_LOGE(TAG, "Failed to allocate memory");
        esp_camera_fb_return(fb);
        return ESP_ERR_NO_MEM;
    }

    // Fill PreData at the start
    PreData *pre = (PreData *)dataOut;
    pre->isVisible = true;
    pre->len = fb->len;
    pre->width = fb->width;
    pre->height = fb->height;
    pre->format = fb->format;
    pre->timestamp = fb->timestamp;

    // Copy image data after PreData
    memcpy(dataOut + headerSize, fb->buf, fb->len);

    // Now chunk and send
    send_data_frame(0x10, dataOut, totalSize);

    free(dataOut);
    esp_camera_fb_return(fb);
    return ESP_OK;
}

void app_main(void)
{

    nvs_flash_init();
    ESP_ERROR_CHECK(esp_netif_init());
    ESP_ERROR_CHECK(esp_event_loop_create_default());
    esp_netif_create_default_wifi_sta();

    wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
    ESP_ERROR_CHECK(esp_wifi_init(&cfg));
    ESP_ERROR_CHECK(esp_wifi_set_storage(WIFI_STORAGE_RAM));
    ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_AP));

    wifi_config_t ap_config = {
        .ap = {
            .ssid = "ESP32-Test",
            .channel = 10,
            .authmode = WIFI_AUTH_OPEN,
            .max_connection = 1,
            .ssid_hidden = 1,
            .beacon_interval = 60000}};
    ESP_ERROR_CHECK(esp_wifi_set_config(WIFI_IF_AP, &ap_config));
    ESP_ERROR_CHECK(esp_wifi_start());
    ESP_ERROR_CHECK(esp_wifi_set_ps(WIFI_PS_NONE));

    esp_log_level_set("wifi", ESP_LOG_DEBUG);

    uint8_t mac_addr[6];
    esp_read_mac(mac_addr, ESP_MAC_WIFI_SOFTAP);
    ESP_LOGI(TAG, "ESP32 MAC: %02X:%02X:%02X:%02X:%02X:%02X",
             mac_addr[0], mac_addr[1], mac_addr[2], mac_addr[3], mac_addr[4], mac_addr[5]);

    camera_init();

    vTaskDelay(pdMS_TO_TICKS(300)); // Let the camera wake up fully

    while (1)
    {

        gpio_config_t usb_phy_conf = {
            .pin_bit_mask = (1ULL << 19) | (1ULL << 20),
            .mode = GPIO_MODE_OUTPUT,
            .pull_up_en = GPIO_PULLUP_ENABLE,
            .pull_down_en = GPIO_PULLDOWN_DISABLE,
            .intr_type = GPIO_INTR_DISABLE,
        };
        gpio_config(&usb_phy_conf);
      
        printf("[MAIN] Start task\n");
      
        LEP_CONFIG.agc_set_enabled = true;
        LEP_CONFIG.emissivity = 100;
        LEP_CONFIG.gain_mode = LEP_GAIN_AUTO;
      
        // initialize spi, i2c and gpio for lepton
        if (!lepton_io_init())
        {
          printf("[MAIN] Error: I/O init failed");
          while (1)
          {
            vTaskDelay(pdMS_TO_TICKS(100));
          }
        }
      
        // allocate lepton buffers
        if (!lepton_buffer_init())
        {
          printf("[MAIN] Error: Memory init failed");
          while (1)
          {
            vTaskDelay(pdMS_TO_TICKS(100));
          }
        }
      
        // wait for lepton to initialize
        vTaskDelay(pdMS_TO_TICKS(1000));;
      
        // Attempt to initialize the VoSPI interface
        if (vospi_init() != ESP_OK)
        {
          printf("[MAIN] Error: Lepton VoSPI initialization failed\n");
          while (1)
          {
            vTaskDelay(pdMS_TO_TICKS(100));
          }
        }
      
        // initialize lepton
        if (!lepton_init())
        {
          printf("[MAIN] Error: Lepton CCI initialization failed\n");
          while (1)
          {
            vTaskDelay(pdMS_TO_TICKS(100));
          }
        }
      
        // disable data from lepton
        gpio_set_level(LEP_CSN_PIN, 1);
      
        printf("LEPTON INIT DONE");

        int64_t start = esp_timer_get_time();
        camera_capture();
        int64_t end = esp_timer_get_time();

        int64_t duration = end - start;

        printf("%lf FPS, %lf SPF\n", 1 / (duration / 1000000.0), duration / 1000000.0);
    }
}