#include <LiquidCrystal_I2C.h>
#include <NewPing.h>
#include <DHT.h>
#include <WiFi.h>
#include <HTTPClient.h>

#define DHTPIN 14
#define DHTTYPE DHT22
#define TRIGGER_PIN 18
#define ECHO_PIN 17
#define MAX_DISTANCE 200
#define PHOTO_PIN 34
#define BUZZER_PIN 12
#define RED_LED_PIN 19
#define BLUE_LED_PIN 26

const float GAMMA = 0.7;
const float RL10 = 50;
const char* ssid = "Wokwi-GUEST";
const char* password = "";
const char* server = "http://api.thingspeak.com/update";
const char* apiKey = "K4QM3JCOB8FOWVV4";

DHT dht(DHTPIN, DHTTYPE);
LiquidCrystal_I2C lcd(0x27, 16, 2);
NewPing sonar(TRIGGER_PIN, ECHO_PIN, MAX_DISTANCE);

void setup() {
  Serial.begin(115200);
  dht.begin();
  lcd.init();
  lcd.backlight();
  pinMode(BUZZER_PIN, OUTPUT);
  pinMode(RED_LED_PIN, OUTPUT);
  pinMode(BLUE_LED_PIN, OUTPUT);
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
  }
}

void loop() {
  float temperature = dht.readTemperature();
  float humidity = dht.readHumidity();
  float distance = sonar.ping_cm();
  int analogValue = analogRead(PHOTO_PIN);
  float voltage = analogValue / 4095.0 * 3.3 ;
  float resistance = 2000 * voltage / (1 - voltage / 3.3);
  float lightIntensityLux = pow(RL10 * 1e3 * pow(10, GAMMA) / resistance, (1 / GAMMA))/1.808;

  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Temp: ");
  lcd.print(temperature);
  lcd.print("C");
  delay(500);
  lcd.setCursor(0, 1);
  lcd.print("Humidity: ");
  lcd.print(humidity);
  lcd.print("%");
  delay(500);
  lcd.setCursor(0, 0);
  lcd.print("Light: ");
  lcd.print(lightIntensityLux);
  lcd.print(" lux");
  delay(500);
  lcd.setCursor(0, 1);
  lcd.print("Water: ");
  lcd.print(distance);
  lcd.print(" cm");
  delay(1000);

  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.println(" C");
  Serial.print("Humidity: ");
  Serial.print(humidity);
  Serial.println(" %");
  Serial.print("Light Intensity: ");
  Serial.print(lightIntensityLux);
  Serial.println(" lux");
  Serial.print("Water Level: ");
  Serial.print(distance);
  Serial.println(" cm");

  if (temperature > 35 && humidity > 60 && distance < 20 && lightIntensityLux > 200) {
    digitalWrite(RED_LED_PIN, HIGH);
    digitalWrite(BLUE_LED_PIN, LOW);
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Danger!");
    tone(BUZZER_PIN, 1000, 1000);
  } else {
    digitalWrite(RED_LED_PIN, LOW);
    digitalWrite(BLUE_LED_PIN, HIGH);
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Safe");
  }

  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;
    String url = String(server) + "?api_key=" + apiKey + 
                 "&field1=" + String(temperature) +
                 "&field2=" + String(humidity) +
                 "&field3=" + String(distance) +
                 "&field4=" + String(lightIntensityLux);
    http.begin(url);
    int httpResponseCode = http.GET();
    if (httpResponseCode > 0) {
      Serial.print("Data sent to ThingSpeak. Response code: ");
      Serial.println(httpResponseCode);
    } else {
      Serial.print("Error in sending data. HTTP response code: ");
      Serial.println(httpResponseCode);
    }
    http.end();
  } else {
    Serial.println("WiFi not connected");
  }

  delay(1000);
}