#include "DHT.h"
#include <WiFi.h>
#include <HTTPClient.h>
// adds the sensor library

#define DHTPIN 15
//sensor data is connected to GPIO 15
#define DHTTYPE DHT22

const int greenLed = 18;
const int redLed = 19;
const int buzzer = 21;

const char* ssid = "Wokwi-GUEST";
const char* password = "";

String apiKey = "2CL5HW30YLELBGRM";
const char* server = "https://api.thingspeak.com/update";

DHT dht(DHTPIN, DHTTYPE);

void setup() {
  Serial.begin(9600);
  dht.begin();
  //STARTS the sensor
  pinMode(greenLed, OUTPUT);
  pinMode(redLed, OUTPUT);
  pinMode(buzzer, OUTPUT);

 Serial.print("Connecting to WiFi");

  WiFi.begin(ssid, password);

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

  Serial.println();
  Serial.println("WiFi connected!");
}


void loop() {
  float temperature = dht.readTemperature();
  //reads the temperature
  float humidity = dht.readHumidity();
  //reads humidity

  Serial.print("Temperature: ");
  Serial.print(temperature);
  Serial.println(" °C");

  Serial.print("Humidity: ");
  Serial.print(humidity);
  Serial.println(" %");

  if (temperature >= 32){
    digitalWrite(greenLed, LOW);
    digitalWrite(redLed, HIGH);
    digitalWrite(buzzer, HIGH);
    Serial.println("Status: Critically hot - buzzer activated");
    //if temp is more than or equal to 32 on red led and buzzer.
  }

  else if (temperature >= 25){
    digitalWrite(greenLed, LOW);
    digitalWrite(redLed, HIGH);
    digitalWrite(buzzer, LOW);
    Serial.println("Status: Warning - high temperature");
    //if temperature is more than 25 on red led light.
  }

  else if (temperature <= 0){
    digitalWrite(greenLed, LOW);
    digitalWrite(redLed, HIGH);
    digitalWrite(buzzer, HIGH);
    Serial.println("Status: Critically cold - buzzer activated");
    //if temp is less than or equal to 0 on red led and buzzer.
  }

  else if (temperature <= 10){
    digitalWrite(greenLed, LOW);
    digitalWrite(redLed, HIGH);
    digitalWrite(buzzer, LOW);
    Serial.println("Status: Warning - low temperature");
    //if temperature is less than or equal to 10 on redlight.
  }

  else {
    digitalWrite(greenLed, HIGH);
    digitalWrite(redLed, LOW);
    digitalWrite(buzzer, LOW);
    Serial.println("Status: Normal environment");
    //otherwise on green led light.
  }
  
  Serial.println("-----------------");

  if (WiFi.status() == WL_CONNECTED) {
  // if wifi is connected it sends temperature and humidity to ThingSpeak.
    HTTPClient http;
    //builds the web request URL
    String url = String(server) + "?api_key=" + apiKey +
                  "&field1=" + String(temperature) +
                  "&field2=" + String(humidity);
    http.begin(url);
    int httpResponseCode = http.GET();
    Serial.print("HTTP Response code: ");
    Serial.println(httpResponseCode);

    http.end();

  }

  delay(2000);
  //waits 2 secs because DHT sensors shouldnt read too quickly.
}