#include <WiFi.h> // Including WiFi.h library to handle WiFi related tasks 
#include <HTTPClient.h> // Including HTTPClient.h library to use HTTP requests 
#include "DHT.h" // Including DHT library for temperature and humidity sensor
/* ______________________________________________________
    
   configuration wifi et connection whatsapp
 __________________________________________________________*/
// Wi-Fi credentials
const char* ssid = "Wokwi-GUEST"; // Add your WiFi SSID
const char* password = ""; // Add your WiFi password

// WhatsApp API credentials
String apiKey =  // Add your Token number that the bot has sent you on WhatsApp 
String phone_number =  // Add your WhatsApp registered phone number 

// URL String to store the final generated URL
String url;
/*___________________________________________________

 definir les pins aux quelles on relie les capteurs 
_____________________________________________________*/
// DHT Sensor
#define DHTPIN 14 // Pin where the DHT11 is connected 
#define DHTTYPE DHT22 // DHT 22
DHT dht(DHTPIN, DHTTYPE);

// PIR Sensor
#define PIRPIN 15 // Pin where the PIR sensor is connected

// Flame Sensor
#define FLAME_PIN 34 // Pin where the flame sensor is connected 
#define FLAME_BUZZER_PIN 25 // Pin where the flame buzzer is connected

// Gas Sensor
#define GAS_PIN 35 // Pin where the gas sensor is connected 
#define GAS_BUZZER_PIN 26 // Pin where the gas buzzer is connected

// Light Sensor (Photoresistor)
#define LIGHT_PIN 32 // Pin where the photoresistor is connected 
#define LIGHT_LED_PIN 27
void setup() {
    Serial.begin(115200);

    // Initialize WiFi connection
    WiFi.begin(ssid, password); 
    Serial.println("Connecting to WiFi");
    unsigned long startAttemptTime = millis();

    // Timeout for WiFi connection attempt (e.g., 10 seconds)
    while (WiFi.status() != WL_CONNECTED && millis() - startAttemptTime < 10000) { 
        delay(500);
        Serial.print(".");
    }

    if (WiFi.status() != WL_CONNECTED) {
        Serial.println("Failed to connect to WiFi");
        return;
    }

    Serial.println();
    Serial.println("Connected to the WiFi network");

    // Initialize DHT sensor 
    dht.begin();

    // Initialize PIR sensor 
    pinMode(PIRPIN, INPUT);

    // Initialize flame sensor and buzzer 
    pinMode(FLAME_PIN, INPUT); 
    pinMode(FLAME_BUZZER_PIN, OUTPUT);

    // Initialize gas sensor and buzzer 
    pinMode(GAS_PIN, INPUT); 
    pinMode(GAS_BUZZER_PIN, OUTPUT);

    // Initialize light sensor and LED 
    pinMode(LIGHT_PIN, INPUT); 
    pinMode(LIGHT_LED_PIN, OUTPUT);

    // Send an initial message
    message_to_whatsapp("ESP32 is connected and ready.");
}

void loop() {
    // Read sensor data
    float temperature = dht.readTemperature(); // Read temperature as Celsius 
    float humidity = dht.readHumidity(); // Read humidity
    int pirValue = digitalRead(PIRPIN); // Read PIR sensor value
    int flameValue = analogRead(FLAME_PIN); // Read flame sensor value 
    int gasValue = analogRead(GAS_PIN); // Read gas sensor value
    int lightValue = analogRead(LIGHT_PIN); // Read light sensor value

    // Check if any reads failed and exit early (to try again). 
    if (isnan(temperature) || isnan(humidity)) { 
        Serial.println("Failed to read from DHT sensor!"); 
        return;
    }

    // Handle flame sensor
    if (flameValue < 100) { // Adjust the threshold as necessary 
        digitalWrite(FLAME_BUZZER_PIN, HIGH); 
        Serial.println("Flame detected!");
    } else {
        digitalWrite(FLAME_BUZZER_PIN, LOW);
    }

    // Handle gas sensor
    if (gasValue > 300) { // Adjust the threshold as necessary 
        digitalWrite(GAS_BUZZER_PIN, HIGH); 
        Serial.println("Gas detected!");
    } else {
        digitalWrite(GAS_BUZZER_PIN, LOW);
    }

    // Handle light sensor
    if (lightValue < 500) { // Adjust the threshold as necessary 
        digitalWrite(LIGHT_LED_PIN, HIGH); 
        Serial.println("Low light detected!");
    } else {
        digitalWrite(LIGHT_LED_PIN, LOW);
    }

    // Create message
    String message = "Temperature: " + String(temperature) + "°C\n"; 
    message += "Humidity: " + String(humidity) + "%\n";
    message += "Motion detected: " + String(pirValue == HIGH ? "Yes" : "No") + "\n"; 
    message += "Flame detected: " + String(flameValue < 100 ? "Yes" : "No") + "\n"; 
    message += "Gas detected: " + String(gasValue > 300 ? "Yes" : "No") + "\n"; 
    message += "Low light detected: " + String(lightValue < 500 ? "Yes" : "No");

    // Send message to WhatsApp 
    message_to_whatsapp(message);

    // Wait for 10 minutes before sending the next reading
    delay(60000); // 60000 milliseconds = 1 minutes
}

void message_to_whatsapp(String message) {
    // Adding all number, your API key, your message into one complete URL
    url = "https://api.callmebot.com/whatsapp.php?phone=" + phone_number + "&apikey=" + apiKey + "&text=" + urlencode(message);
    postData(); // Calling postData to run the above-generated URL once so that you will receive a message
}

void postData() {
    int httpCode; // Variable used to get the response HTTP code after calling API 
    HTTPClient http; // Declare object of class HTTPClient
    http.begin(url); // Begin the HTTPClient object with generated URL
    httpCode = http.POST(""); // Finally, POST the URL with this function and it will store the HTTP code

    if (httpCode == 200) { // Check if the response HTTP code is 200 
        Serial.println("Sent ok."); // Print message sent ok message
    } else { // If response HTTP code is not 200, it means there is some error 
        Serial.println("Error."); // Print error message
    }
    http.end(); // After calling API, end the HTTP client object
}

String urlencode(String str) { // Function used for encoding the URL 
    String encodedString = "";
    char c;
    char code0; 
    char code1;

    for (int i = 0; i < str.length(); i++) { 
        c = str.charAt(i);
        if (c == ' ') { 
            encodedString += '+';
        } else if (isalnum(c)) { 
            encodedString += c;
        } else {
            code1 = (c & 0xf) + '0'; 
            if ((c & 0xf) > 9) {
                code1 = (c & 0xf) - 10 + 'A';
            }
            c = (c >> 4) & 0xf; 
            code0 = c + '0';
            if (c > 9) {
                code0 = c - 10 + 'A';
            }
            encodedString += '%'; 
            encodedString += code0; 
            encodedString += code1;
        }
    }
    return encodedString;
}