#include <WiFi.h>
#include <ThingSpeak.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27,20,4);

#define trigerPin 12
#define echoPin 13
#define ledPin 14
#define pitch 262
#define CM_TO_INCH 0.393701
#define buzzerPin 27

long duration;
float distance;
float distanceInch;

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

WiFiClient alfa;

unsigned long ChannelID = 1987430;
const char * WriteAPI = "QKBE0N3OL0W8CCGM";


void setup() {
  //SENSOR
  Serial.begin(115200);
  pinMode(trigerPin, OUTPUT);
  pinMode(echoPin, INPUT);

  //LCD
  lcd.begin(20,4);
  lcd.init();

  //BUZZER
  pinMode(buzzerPin, OUTPUT);

  //LED
  pinMode(ledPin, OUTPUT);

  //WiFi
  Serial.println("Scan WiFi...");
  int networks = WiFi.scanNetworks();
  if(networks == 0){
    Serial.println("No WiFi Networks!");
  }
  else{
    Serial.print(networks);
    Serial.println(" Networks Found!");
    for(int i = 0; i < networks; i++)
      Serial.println(WiFi.SSID());
      delay(10);
  }

  //menyambungkan ke wifi
  WiFi.begin(ssid, pass);
  while (WiFi.status() != WL_CONNECTED){
    delay(100);
    Serial.println(".");
  }
  Serial.println("WiFi Connected!");
  Serial.println(WiFi.localIP());

  //memulai program thingspeak
  ThingSpeak.begin(alfa);

}

void loop() {
  
 //looping sensor (membuat sensor wave)
  digitalWrite(trigerPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigerPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigerPin, LOW);

  //membuat durasi
  duration = pulseIn(echoPin, HIGH);

  //mengkalkulasi jarak
  distance = (duration/2) * 0.0343;

  // Convert to inches
  distanceInch = distance * CM_TO_INCH;

  //concider max width of the door = 200 cm
  if(distance<100){
    digitalWrite(ledPin, HIGH);
    delay(1000);

    digitalWrite(ledPin, LOW);
    delay(100);

    lcd.backlight();
    delay(200);
    lcd.setCursor(5,1);
    lcd.print("WARNING!");
    lcd.setCursor(2,2);
    lcd.print("MOTION DETECTED!");

    digitalWrite(buzzerPin, HIGH);
    tone(buzzerPin,600);
    delay(300);
    noTone(100);
    delay(500);
  }
  else{
    digitalWrite(ledPin, LOW);
    lcd.backlight();
    lcd.setCursor(5,1);
    lcd.print("STAND BY");
    lcd.setCursor(1,2);
    lcd.print("NO MOTION DETECTED");
  }

 int y = ThingSpeak.writeField (ChannelID, 1, distance, WriteAPI);

  //mengambil data dari thingspeak
  if(distance<100){
    Serial.println("WARNING!");
    Serial.println("distance(cm): " + String(distance));    
  }

  delay(2000);
}