#include <DHTesp.h>
#include <ThingSpeak.h>
#include <WiFi.h>
// Define the WiFi credentials and ThingSpeak channel details
WiFiClient client;
const long myChannelNumber = 2616905;
const char* myWriteAPIKey = "YYDYO0MKVBBYBUDR";
int statusCode;

// DHT sensor setup
DHTesp dht;
TempAndHumidity th;

// Pin definitions
const int trg = 14;
const int echo = 13;
const int grn = 25;
const int org = 21;
const int red = 19;
const int buzzer = 2;

// Distance variable
float dis = 0;

void setup() {
  Serial.begin(115200);
  ThingSpeak.begin(client);

  Serial.println("Hello, ESP32!");

  pinMode(trg, OUTPUT);
  pinMode(echo, INPUT);
  pinMode(grn, OUTPUT);
  pinMode(org, OUTPUT);
  pinMode(red, OUTPUT);
  pinMode(buzzer, OUTPUT);

  dht.setup(18, DHTesp::DHT22);
}

float ultra() {
  digitalWrite(trg, HIGH);
  delay(10);  // Short pulse duration
  digitalWrite(trg, LOW);

  // Wait for the pulse to start and measure the duration
  float duration = pulseIn(echo, HIGH);
  dis = duration * 0.034 / 2;
  return dis;
}

void loop() {
  // Measure distance
  dis = ultra();

  // Get temperature and humidity data from DHT sensor
  th = dht.getTempAndHumidity();

  // Handle DHT sensor read errors
  if (isnan(th.temperature) || isnan(th.humidity)) {
    Serial.println("Failed to read from DHT sensor!");
    return;  // Exit loop to avoid using invalid data
  }

  // Set ThingSpeak fields
  ThingSpeak.setField(1, th.temperature);  // Field 1: Temperature
  ThingSpeak.setField(2, th.humidity);     // Field 2: Humidity
  ThingSpeak.setField(3, dis);             // Field 3: Distance

  // Send data to ThingSpeak
  statusCode = ThingSpeak.writeFields(myChannelNumber, myWriteAPIKey);

  if (statusCode == 200) {
    Serial.println("Channel update successful.");
  } else {
    Serial.println("Problem Writing data. HTTP error code: " + String(statusCode));
  }

  // Determine safety status and take action
  if (th.temperature <= 30 && th.humidity >= 70 && dis >= 300) {
    digitalWrite(grn, HIGH);
    digitalWrite(org, LOW);
    digitalWrite(red, LOW);
    Serial.println("You are safe!!");
    noTone(buzzer);
  } else if ((th.temperature > 30 && th.temperature < 70) && 
             (th.humidity > 30 && th.humidity < 70) && 
             (dis > 200 && dis < 300)) {
    digitalWrite(org, HIGH);
    digitalWrite(grn, LOW);
    digitalWrite(red, LOW);
    Serial.println("You are unsafe!!");
    noTone(buzzer);
  } else {
    digitalWrite(red, HIGH);
    digitalWrite(org, LOW);
    digitalWrite(grn, LOW);
    Serial.println("You are in danger!!!!!!");
    tone(buzzer, 10000);
  }

  delay(10000); // Delay between readings
}