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

// WiFi Credentials
const char* ssid = "YOUR_WIFI_SSID";
const char* password = "YOUR_WIFI_PASSWORD";

// Camera Module Pin Configuration for ESP32 AI-Thinker Module
#define PWDN_GPIO_NUM     32
#define RESET_GPIO_NUM    -1
#define XCLK_GPIO_NUM      0
#define SIOD_GPIO_NUM     26
#define SIOC_GPIO_NUM     27
#define Y9_GPIO_NUM       35
#define Y8_GPIO_NUM       34
#define Y7_GPIO_NUM       39
#define Y6_GPIO_NUM       36
#define Y5_GPIO_NUM       21
#define Y4_GPIO_NUM       19
#define Y3_GPIO_NUM       18
#define Y2_GPIO_NUM        5
#define VSYNC_GPIO_NUM    25
#define HREF_GPIO_NUM     23
#define PCLK_GPIO_NUM     22

// Arduino Uno Communication Pins
#define RX_PIN 2   // ESP32 RX connected to Arduino TX
#define TX_PIN 4   // ESP32 TX connected to Arduino RX

// Traffic Light Control Pins on Arduino
#define GREEN_LIGHT_PIN 8
#define YELLOW_LIGHT_PIN 9

void setupCamera() {
  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;
  
  // Configure resolution and frame rate
  config.frame_size = FRAMESIZE_VGA;  // 640x480
  config.jpeg_quality = 10;
  config.fb_count = 2;

  // Initialize camera
  esp_err_t err = esp_camera_init(&config);
  if (err != ESP_OK) {
    Serial.printf("Camera init failed with error 0x%x", err);
    return;
  }
}

void connectToWiFi() {
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nWiFi Connected");
}

bool detectVehicles() {
  camera_fb_t *fb = esp_camera_fb_get();
  if (!fb) {
    Serial.println("Camera capture failed");
    return false;
  }

  // TODO: Implement advanced vehicle detection using OpenCV or 
  // machine learning algorithms for more accurate detection
  
  // Simple brightness-based detection as a placeholder
  int brightnessThreshold = 100;
  int brightnessSum = 0;
  
  for(int i = 0; i < fb->len; i++) {
    brightnessSum += fb->buf[i];
  }
  
  esp_camera_fb_return(fb);
  
  // Return true if average brightness suggests vehicle presence
  return (brightnessSum / fb->len > brightnessThreshold);
}

void setup() {
  Serial.begin(115200);
  setupCamera();
  connectToWiFi();

  pinMode(GREEN_LIGHT_PIN, OUTPUT);
  pinMode(YELLOW_LIGHT_PIN, OUTPUT);
}

void loop() {
  bool directionOneDetected = detectVehicles();
  delay(100);  // Small delay for second detection
  bool directionTwoDetected = detectVehicles();

  if (directionOneDetected && directionTwoDetected) {
    // Vehicles detected in both directions
    digitalWrite(GREEN_LIGHT_PIN, LOW);
    digitalWrite(YELLOW_LIGHT_PIN, HIGH);
  } else if (directionOneDetected || directionTwoDetected) {
    // Vehicle detected in only one direction
    digitalWrite(GREEN_LIGHT_PIN, HIGH);
    digitalWrite(YELLOW_LIGHT_PIN, LOW);
  } else {
    // No vehicles
    digitalWrite(GREEN_LIGHT_PIN, LOW);
    digitalWrite(YELLOW_LIGHT_PIN, LOW);
  }

  delay(1000);  // Wait before next detection cycle
}