#include <LiquidCrystal_I2C.h>                                   // For 16*2 LCD Display
#include <Wire.h>


//#include <WiFi.h>
#include <ESP32Servo.h>                                          // For Servo Motor

#define SERVO_PIN 2                                              // Define servo motor pin

#define I2C_SDA 21
#define I2C_SCL 22

TwoWire I2CBME = TwoWire(0);                                     // I2C Bus Create

#define IR1_PIN 12                                               // Define IR sensor 1 pin
#define IR2_PIN 13                                               // Define IR sensor 2 pin
#define IR3_PIN 14                                               // Define IR sensor 3 pin
#define IR4_PIN 15                                               // Define IR sensor 4 pin


int lcdColumns = 16;                                             // Number of Coloums in LCD Display
int lcdRows = 2;                                                 // Number of Rows in LCD Display

LiquidCrystal_I2C lcd(0x27, lcdColumns, lcdRows);  


Servo servo;                                                     // Create a Servo object

void setup() {


  Wire.begin(I2C_SDA, I2C_SCL);
  I2CBME.begin(I2C_SDA, I2C_SCL, 400000);                        // initialize LCD
                       
  lcd.backlight();                                               // turn on LCD backlight 
  
  pinMode(IR1_PIN, INPUT);                                       // Set IR sensor 1 pin as input
  pinMode(IR2_PIN, INPUT);                                       // Set IR sensor 2 pin as input
  pinMode(IR3_PIN, INPUT);                                       // Set IR sensor 3 pin as input
  pinMode(IR4_PIN, INPUT);                                       // Set IR sensor 4 pin as input

  servo.attach(SERVO_PIN);                                       // Attach the servo motor to the specified pin

  Serial.begin(9600);                                            // Start serial communication

            // Start the web server
}

void loop() {

  lcd.setCursor(0, 0);                                           // set cursor to first column, first row
  lcd.print("Smart Parking");                                    // print message on Display

  int ir1 = digitalRead(IR1_PIN);                                // Read the state of IR sensor 1
  int ir2 = digitalRead(IR2_PIN);                                // Read the state of IR sensor 2
  int ir3 = digitalRead(IR3_PIN);                                // Read the state of IR sensor 3
  int ir4 = digitalRead(IR4_PIN);                                // Read the state of IR sensor 4

  Serial.print("IR Sensor Values: ");                            // Print Values of sensors on Serial Monitor
  Serial.print(ir1);
  Serial.print(", ");
  Serial.print(ir2);
  Serial.print(", ");
  Serial.print(ir3);
  Serial.print(", ");
  Serial.println(ir4);

  if (ir1 == HIGH ) {                                            // Entry Sensor detect Obstacle
    if (ir3 == LOW)  {                                           // SLot 1 is Empty
      lcd.setCursor(0,1);
      lcd.print("1");                                            // Print slot Number 1
      servo.write(90);                                           // ROtate Servo to 90 Degree
      delay(5000);                                               // Wait for 5 Sec
      servo.write(-90);                                          // Rotate Servo to -90 Degree
      lcd.clear();                                               // Clear display
    }

    else if (ir3 == HIGH && ir4 == LOW) {                        // Slot 2 is Empty
      lcd.setCursor(0,1);
      lcd.print("2");
      servo.write(90);
      delay(5000);
      servo.write(-90);
      lcd.clear();
    }

    else if (ir3 == LOW && ir4 == LOW) {                         // Both Slots are Empty
      lcd.setCursor(0,1);
      lcd.print("1");
      delay(2000);
      servo.write(90);
      delay(5000);
      servo.write(-90);
      lcd.clear();
    }

    else if (ir3 == HIGH && ir4 == HIGH) {                       // Both Slots are Full
      lcd.setCursor(0,1);
      lcd.print("FULL !!!");
      delay(2000);
      lcd.clear();
    }
  }

  if (ir2 == HIGH ) {                                            // Exit Sensor detect an obstacle
    servo.write(90);
    delay(5000);
    servo.write(-90);
  }
  
  else {
    servo.write(0);                                              // No Detection
  }

  delay(1000);                                                    // Wait for 100 milliseconds before checking the IR sensors again

  }