#include <WiFi.h>
#include <WiFiClientSecure.h>
#include <MQTT.h>
#include <HTTPClient.h>
#include <DHT.h>

WiFiClient net;
MQTTClient mqtt;

unsigned long lastMillis = 0;

// LED pin mapping
const int LED1_PIN = 14;
const int LED2_PIN = 12;
const int LED3_PIN = 13;

// DHT22 sensor settings
#define DHTPIN 27
#define DHTTYPE DHT22
DHT dht(DHTPIN, DHTTYPE);

// Device identification
const char* deviceName = "Wokwi-ESP32";

// Google Apps Script URL - REPLACE WITH YOUR URL
const char* googleSheetsScriptUrl = "https://script.google.com/macros/s/AKfycbyWdegZWrTjn_Z-MgafLmLo9GICarMfLopLNvrJA2m3dziOOnAOUxukgXNpiHkJX0Gw/exec";

// Sensor reading intervals
unsigned long lastSensorRead = 0;
const unsigned long sensorReadInterval = 5000;  // Read sensor every 5 seconds

unsigned long lastGoogleSheetsLog = 0;
const unsigned long googleSheetsLogInterval = 600000;   // Log to sheets every 60 seconds

// Store latest sensor readings
float currentTemperature = 0;
float currentHumidity = 0;

// Flag for first reading
bool firstReadingComplete = false;

void connectWiFi() {
  Serial.print("Connecting to Wi-Fi ");
  WiFi.begin("Wokwi-GUEST", "", 6);

  while (WiFi.status() != WL_CONNECTED) {
    delay(250);
    Serial.print(".");
  }
  Serial.println(" connected!");
}

void connectMQTT() {
  Serial.print("Connecting to MQTT broker ");
  while (!mqtt.connect("moltbot-wokwi-esp32", "ariffin", "password")) {
    Serial.print(".");
    delay(250);
  }
  Serial.println(" connected!");
  Serial.println();

  // Subscribe to the control topic
  mqtt.subscribe("moltbot-wokwi-esp32/control");
}

void messageReceived(String &topic, String &payload) {
  Serial.println("incoming: " + topic + " - " + payload);

  if (topic == "moltbot-wokwi-esp32/control") {
    // Parse payload format: "gpio,state"
    int commaIndex = payload.indexOf(',');
    if (commaIndex > 0) {
      int gpio = payload.substring(0, commaIndex).toInt();
      int state = payload.substring(commaIndex + 1).toInt();

      Serial.print("GPIO: ");
      Serial.print(gpio);
      Serial.print(" State: ");
      Serial.println(state);

      // Control the LED based on GPIO pin
      digitalWrite(gpio, state);
    } else {
      Serial.println("Invalid payload format. Expected: gpio,state");
    }
  }
}

void sendToGoogleSheets(float temperature, float humidity) {
  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;
    
    // Use WiFiClientSecure for HTTPS
    WiFiClientSecure client;
    client.setInsecure(); // Skip certificate validation for simplicity

    http.begin(client, googleSheetsScriptUrl);
    http.addHeader("Content-Type", "application/json");

    // Create JSON payload with device name
    String jsonPayload = "{\"device\":\"" + String(deviceName) + 
                        "\",\"temperature\":" + String(temperature, 2) +
                        ",\"humidity\":" + String(humidity, 2) + "}";

    Serial.println("==== Log to Google Sheets ====");
    Serial.println(jsonPayload);

    int httpResponseCode = http.POST(jsonPayload);

    if (httpResponseCode > 0) {
      String response = http.getString();
      Serial.print("✓ HTTP Response code: ");
      Serial.println(httpResponseCode);
      
      // Only print response if it's a success (200-299)
      if (httpResponseCode >= 200 && httpResponseCode < 300) {
        Serial.print("Response: ");
        Serial.println(response);
      } else {
        Serial.println("Note: Redirect or error response (see code above)");
      }
    } else {
      Serial.print("✗ Error sending data: ");
      Serial.println(httpResponseCode);
    }

    http.end();
  } else {
    Serial.println("✗ WiFi disconnected, cannot send data");
  }
}

void readSensor() {
  float humidity = dht.readHumidity();
  float temperature = dht.readTemperature();

  // Check if readings are valid
  if (isnan(humidity) || isnan(temperature)) {
    Serial.println("✗ Failed to read from DHT sensor!");
    return;
  }

  // Update current readings
  currentTemperature = temperature;
  currentHumidity = humidity;

  Serial.println("======== DHT22 Reading =======");
  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.println(" °C");
  Serial.print("Humidity: ");
  Serial.print(humidity);
  Serial.println(" %");
  Serial.println();
}

void setup() {
  Serial.begin(115200);
  Serial.println("Hello, Moltbot ESP32!");
  Serial.print("Device Name: ");
  Serial.println(deviceName);

  // Initialize LED pins
  pinMode(LED1_PIN, OUTPUT);
  pinMode(LED2_PIN, OUTPUT);
  pinMode(LED3_PIN, OUTPUT);

  // Turn off all LEDs initially
  digitalWrite(LED1_PIN, LOW);
  digitalWrite(LED2_PIN, LOW);
  digitalWrite(LED3_PIN, LOW);

  // Initialize DHT22 sensor
  dht.begin();
  Serial.println("DHT22 sensor initialized");

  // Connect to Wokwi's Wi-Fi
  connectWiFi();

  mqtt.begin("mqtt.ariffin.cc", net);
  mqtt.onMessage(messageReceived);

  // Connect to MQTT Broker
  connectMQTT();

  Serial.println("======== ESP32 Ready =========");
  Serial.println("- LED control via MQTT");
  Serial.println("- DHT22 sensor logging to Google Sheets");
  Serial.println("- Reading sensor every 5 seconds");
  Serial.println("- Logging to sheets every 60 seconds");
  Serial.println();

  // Wait 2 seconds for sensor to stabilize, then take first reading
  delay(2000);
  readSensor();
  
  // Send first reading immediately
  if (!isnan(currentTemperature) && !isnan(currentHumidity)) {
    sendToGoogleSheets(currentTemperature, currentHumidity);
    firstReadingComplete = true;
    lastGoogleSheetsLog = millis();  // Reset sheet log timer
  }
}

void loop() {
  delay(10); // this speeds up the simulation

  mqtt.loop();
  delay(10);  // <- fixes some issues with WiFi stability

  // Maintain WiFi connection
  if (WiFi.status() != WL_CONNECTED) {
    connectWiFi();
  }

  // Maintain MQTT connection
  if (!mqtt.connected()) {
    connectMQTT();
  }

  unsigned long currentMillis = millis();

  // Read sensor every 5 seconds
  if (currentMillis - lastSensorRead >= sensorReadInterval) {
    lastSensorRead = currentMillis;
    readSensor();
  }

  // Log to Google Sheets every 60 seconds (after first reading)
  if (firstReadingComplete && (currentMillis - lastGoogleSheetsLog >= googleSheetsLogInterval)) {
    lastGoogleSheetsLog = currentMillis;
    
    // Only send if we have valid readings
    if (!isnan(currentTemperature) && !isnan(currentHumidity)) {
      sendToGoogleSheets(currentTemperature, currentHumidity);
    }
  }
}