#include <WiFi.h>
#include <HTTPClient.h>
#include <UrlEncode.h>

#define echoPin 27
#define trigPin 26
#define ledPin 21

const char* ssid = "nepatronix_2.4";//Enter your SSID 
const char* password = "CLB269DA03";//Enter your password

String phoneNumber = "+34644867049"; //country_code + phone number
String apiKey = "2957777";

void setup() {
  Serial.begin(115200);
  pinMode(echoPin, INPUT);
  pinMode(trigPin,OUTPUT);
  pinMode(ledPin,OUTPUT);
  
  WiFi.begin(ssid, password);
  Serial.println("Connecting");
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("");
  Serial.print("Connected to WiFi network with IP Address: ");
  Serial.println(WiFi.localIP());

  // Send Message to WhatsAPP
  sendAlert("Your system is ready!");
}

void loop() {
  // Start a new measurement:
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  // Read the result:
  int duration = pulseIn(echoPin, HIGH);
  Serial.print("Distance in CM: ");
  Serial.println(duration / 58);
  int sensorValue = duration/58;
  if (sensorValue < 15) {
    digitalWrite(ledPIN, HIGH);
    sendAlert("Warning!");
  } else {
    digitalWrite(ledPIN, LOW);
  }
}


void sendAlert(String message) {

  // Data to send with HTTP POST
  String url = "https://api.callmebot.com/whatsapp.php?phone=" + phoneNumber + "&apikey=" + apiKey + "&text=" + urlEncode(message);
  HTTPClient http;
  http.begin(url);

  // Specify content-type header
  http.addHeader("Content-Type", "application/x-www-form-urlencoded");

  // Send HTTP POST request
  int httpResponseCode = http.POST(url);
  if (httpResponseCode == 200) {
    Serial.print("Message sent successfully");
  }
  else {
    Serial.println("Error sending the message");
    Serial.print("HTTP response code: ");
    Serial.println(httpResponseCode);
  }

  // Free resources
  http.end();
}void setup() {
  // put your setup code here, to run once:

}

void loop() {
  // put your main code here, to run repeatedly:

}