#include <WiFi.h>
#include "esp_camera.h"
#include "esp_http_server.h"

#define CAMERA_MODEL_XIAO_ESP32S3
#include "camera_pins.h"

// ==== WIFI ====
const char* ssid     = "EDS_Shop_24";
const char* password = "eds12345";

// Forward declarations
static esp_err_t stream_handler(httpd_req_t *req);
void startCameraServer();

void setup() {
  delay(1500);
  Serial.begin(115200);
  while (!Serial) { delay(10); }

  Serial.println("\nBooting XIAO ESP32S3 Camera...");

  // ==== CAMERA CONFIG ====
  camera_config_t config;
  config.ledc_channel = LEDC_CHANNEL_0;
  config.ledc_timer   = LEDC_TIMER_0;

  config.pin_d0 = Y2_GPIO_NUM;
  config.pin_d1 = Y3_GPIO_NUM;
  config.pin_d2 = Y4_GPIO_NUM;
  config.pin_d3 = Y5_GPIO_NUM;
  config.pin_d4 = Y6_GPIO_NUM;
  config.pin_d5 = Y7_GPIO_NUM;
  config.pin_d6 = Y8_GPIO_NUM;
  config.pin_d7 = Y9_GPIO_NUM;

  config.pin_xclk  = XCLK_GPIO_NUM;
  config.pin_pclk  = PCLK_GPIO_NUM;
  config.pin_vsync = VSYNC_GPIO_NUM;
  config.pin_href  = HREF_GPIO_NUM;

  config.pin_sscb_sda = SIOD_GPIO_NUM;
  config.pin_sscb_scl = SIOC_GPIO_NUM;

  config.pin_pwdn  = PWDN_GPIO_NUM;
  config.pin_reset = RESET_GPIO_NUM;

  config.xclk_freq_hz = 20000000;
  config.pixel_format = PIXFORMAT_JPEG;

  if (psramFound()) {
    config.frame_size = FRAMESIZE_QVGA;
    config.jpeg_quality = 12;
    config.fb_count = 2;
  } else {
    config.frame_size = FRAMESIZE_QQVGA;
    config.fb_count = 1;
  }

  Serial.println("Initializing camera...");
  esp_err_t err = esp_camera_init(&config);
  if (err != ESP_OK) {
    Serial.printf("Camera init failed 0x%x\n", err);
    while (true) delay(100);
  }
  Serial.println("Camera OK!");

  // ==== WIFI ====
  Serial.println("Connecting to WiFi...");
  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }

  Serial.print("\nWiFi connected. IP: ");
  Serial.println(WiFi.localIP());

  startCameraServer();
}

void loop() {
  delay(10);
}

// ==== STREAM HANDLER ====
static httpd_handle_t camera_httpd = NULL;

static esp_err_t stream_handler(httpd_req_t *req) {
  camera_fb_t *fb = NULL;
  esp_err_t res = ESP_OK;
  char buf[64];

  httpd_resp_set_type(req, "multipart/x-mixed-replace; boundary=frame");

  while (true) {
    fb = esp_camera_fb_get();
    if (!fb) {
      Serial.println("Camera capture failed");
      return ESP_FAIL;
    }

    size_t hlen = snprintf(buf, 64,
      "--frame\r\nContent-Type: image/jpeg\r\nContent-Length: %u\r\n\r\n",
      fb->len);

    res = httpd_resp_send_chunk(req, buf, hlen);
    if (res == ESP_OK)
      res = httpd_resp_send_chunk(req, (const char*)fb->buf, fb->len);

    esp_camera_fb_return(fb);

    if (res != ESP_OK)
      break;

    res = httpd_resp_send_chunk(req, "\r\n", 2);
    if (res != ESP_OK)
      break;
  }

  return res;
}

// ==== START SERVER ====
void startCameraServer() {
  httpd_config_t config = HTTPD_DEFAULT_CONFIG();

  httpd_uri_t uri = {
    .uri      = "/",
    .method   = HTTP_GET,
    .handler  = stream_handler,
    .user_ctx = NULL
  };

  httpd_start(&camera_httpd, &config);
  httpd_register_uri_handler(camera_httpd, &uri);

  Serial.println("\n===== CAMERA STREAM READY =====");
  Serial.print("Open in browser: http://");
  Serial.print(WiFi.localIP());
  Serial.println("/");
}