#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <ESP32Servo.h>
#include <WiFi.h>
#include <ThingSpeak.h>

char ssid[] = "Wokwi-GUEST";
char pass[] = "";

WiFiClient client;
long myChannelNumber = 2729019;
const char *myWriteAPIKey = "CL9YNLVFSCQBW2L0";
int statusCode;

const int pirPin = 2;           // PIR motion sensor pin
const int greenLedPin = 12;     // Green LED pin
const int redLedPin = 13;       // Red LED pin
const int buzzerPin = 4;        // Buzzer pin

const int lcdColumns = 21;      // LCD column size
const int lcdRows = 2;          // LCD row size

int R = 0, B = 0, M = 0;        // Variables for ThingSpeak fields
bool doorClosed = false;        // Flag to track if door is closed

LiquidCrystal_I2C lcd(0x27, lcdColumns, lcdRows);  // Initialize LCD
Servo servo;                   // Initialize Servo object

void setup() {
  pinMode(pirPin, INPUT);
  pinMode(greenLedPin, OUTPUT);
  pinMode(redLedPin, OUTPUT);
  pinMode(buzzerPin, OUTPUT);

  servo.attach(18);  // Attach servo to pin 18
  servo.write(90);   // Set servo to 90 degrees (open door)
  

  Serial.begin(115200);  // Start serial communication
  WiFi.mode(WIFI_STA);   // Set WiFi to station mode
  ThingSpeak.begin(client);  // Initialize ThingSpeak

  lcd.init();  // Initialize LCD
  lcd.backlight();  // Turn on LCD backlight
  lcd.print("Door open");
  delay(2000);  // Initial display time
}

void connectWiFi() {
  if (WiFi.status() != WL_CONNECTED) {
    Serial.print("Attempting to connect to WiFi");
    WiFi.begin(ssid, pass);
    while (WiFi.status() != WL_CONNECTED) {
      Serial.print(".");
      delay(500);
    }
    Serial.println("\nConnected to WiFi.");
  }
}

void loop() {
  connectWiFi();  // Ensure WiFi is connected

  delay(5000);  // Give time for any pending WiFi connections

  // Check PIR sensor state
  int pirState = digitalRead(pirPin);
  Serial.println("PIR State: " + String(pirState));  // Debugging output

  if (pirState == HIGH && !doorClosed) {  // Motion detected and door not yet closed
    doorClosed = true;  // Set door to closed state
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Motion Detected!");

    digitalWrite(redLedPin, HIGH);  // Turn on red LED (indicating alarm)
    tone(buzzerPin,0);           // Activate buzzer at 500Hz
    servo.write(0);                 // Move servo to 0 degrees (close door)
    
    lcd.setCursor(0, 1);
    lcd.print("Door Closed");

    // Update status for ThingSpeak
    R = 1;  // Red LED on
    B = 1;  // Buzzer on
    M = 1;  // Motion detected
  }

  // Update ThingSpeak fields with sensor data
  ThingSpeak.setField(1, B);  // Field 1: Buzzer status (0 or 1)
  ThingSpeak.setField(2, M);  // Field 2: Motion detection status (0 or 1)
  ThingSpeak.setField(3, R);  // Field 3: Red LED status (0 or 1)

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

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

  delay(5000);  // Wait for 5 seconds before the next loop
}