#include <WiFi.h>
#include "DHT.h"
#include <ESP_Mail_Client.h>

// ================= WIFI =================
#define WIFI_SSID "Wokwi-GUEST"
#define WIFI_PASSWORD ""

// ================= DHT =================
#define DHTPIN 4
#define DHTTYPE DHT22
DHT dht(DHTPIN, DHTTYPE);

// ================= SMTP (MAILTRAP) =================
#define SMTP_HOST "smtp.gmail.com"
#define SMTP_PORT 587

#define AUTHOR_EMAIL "[email protected]"
#define AUTHOR_PASSWORD "vygyrzvcfpkqtbmd"
#define RECIPIENT_EMAIL "[email protected]"

// ================= THRESHOLD =================
float thresholdTemp = 30.0;

// ================= SMTP SESSION =================
SMTPSession smtp;

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

  // WiFi connect
  WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
  Serial.print("Connecting to WiFi");

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

  dht.begin();
}

void loop() {
  float temp = dht.readTemperature();

  if (isnan(temp)) {
    Serial.println("DHT read failed!");
    delay(2000);
    return;
  }

  Serial.print("Temperature: ");
  Serial.println(temp);

  if (temp > thresholdTemp) {
    
    Serial.println("⚠️ Threshold exceeded! Sending email...");
    smtp.debug(1);
    sendEmail(temp);
    delay(60000); // avoid repeated emails
  }

  delay(5000);
}

// ================= EMAIL FUNCTION =================
void sendEmail(float temp) {
  SMTP_Message message;

  message.sender.name = "ESP32 Alert";
  message.sender.email = AUTHOR_EMAIL;
  message.subject = "Temperature Alert!";
  message.addRecipient("User", RECIPIENT_EMAIL);

  String body = "Temperature exceeded threshold!\n";
  body += "Current Temperature: " + String(temp) + " C";

  message.text.content = body.c_str();

  ESP_Mail_Session session;
  session.server.host_name = SMTP_HOST;
  session.server.port = SMTP_PORT;
  session.login.email = AUTHOR_EMAIL;
  session.login.password = AUTHOR_PASSWORD;

  if (!smtp.connect(&session)) {
    Serial.println("SMTP connection failed!");
    return;
  }

  if (!MailClient.sendMail(&smtp, &message)) {
    Serial.println("Error sending Email: " + smtp.errorReason());
  } else {
    Serial.println("Email sent successfully!");
  }
}