//************** PIN Connection *****************
//Relay: IN --> D4
//LCD: SCL --> SCL, SDA --> SDA, GND --> GND, VCC --> 5V
//Keypad: D6 - D13 of UNO
//Coin Acceptor: DC12V --> +ve Power Jack, COIN --> Signal, GND --> -ve Power Jack

#include <Wire.h>
#include <Arduino.h>
//Include LCD display library for I2C
#include <LiquidCrystal_I2C.h>
//Include Keypad library
#include <Keypad.h>

const int coin = 2;
boolean insert = false;
volatile int pulse = 0;
float total = 0.00;
float cointdetect = 0;

const int Password_Length = 7;
// Character to hold password input
String Data;
// Password
String PassWord = "1234567";

// Pin connected from Relay to UNO
int LOCK = 4;

// Counter for character entries
byte data_count = 0;

// Character to hold key input
char customKey;

// Constants for row and column sizes
const byte ROWS = 4;
const byte COLS = 4;

// Array to represent keys on keypad
char hexaKeys[ROWS][COLS] = {
  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'*', '0', '#', 'D'}
};

// Connections to Arduino pin
byte rowPins[ROWS] = {10, 11, 12, 13};
byte colPins[COLS] = {6, 7, 8, 9};

// Create keypad object
Keypad customKeypad = Keypad(makeKeymap(hexaKeys), rowPins, colPins, ROWS, COLS);

// Create LCD object : Use 0x27 If 0x3F Doesn't work
LiquidCrystal_I2C lcd(0x27, 20, 4);

void setup() 
{
  // put your setup code here, to run once:
  Serial.begin(9600);
  attachInterrupt(digitalPinToInterrupt(2), coinInterrupt, RISING);
  delay(1000);
  lcd.init();
  lcd.backlight();

  // Set LOCK as an OUTPUT pin
  pinMode(LOCK, OUTPUT);
}

void loop() 
{
  //************** Coin Acceptor ***************

  while(insert)
  {
    if (insert) 
    {
      insert = false;
      Serial.println("coin detected!");
      delay(50);
    }
  delay (200);
  }
  
  if(pulse == 1)
    cointdetect = 0.10;

  if(pulse == 2)
    cointdetect = 0.10;

  if(pulse == 3)
    cointdetect = 0.20;

  if(pulse == 4)
    cointdetect = 0.20;

  if(pulse == 5)
    cointdetect = 0.50;

  if(pulse == 6)
    cointdetect = 0.50;

  if(pulse != 0)
    total = total + cointdetect;
  
  pulse = 0;
  
  Serial.println(total);

  lcd.setCursor(0, 0);
  lcd.print("RM ");
  lcd.print(total);
  lcd.print(" ");

  //****************** KeyPad ******************

  lcd.setCursor(0, 2);
  lcd.print("Enter Password:");

  // Look for keypress
  customKey = customKeypad.getKey();
  if (customKey) 
  {
    // Enter keypress into array and increment counter
    Data += customKey;
    lcd.setCursor(data_count, 3);
    lcd.print(Data[data_count]);
    data_count++;
  }

  // See if we have reached the password length
  if (data_count == Password_Length) 
  {
    lcd.clear();
    lcd.setCursor(0, 2);
    if (Data == PassWord) 
    {
      // Correct Password
      lcd.print("Correct");
      total = 0.00;
      // Turn on relay for 5 seconds
      digitalWrite(LOCK, HIGH);
      delay(3000);
      digitalWrite(LOCK, LOW);
    }
    else 
    {
      // Incorrect Password
      lcd.print("Incorrect");
      delay(1000);
    }

    // Clear data and LCD display
    lcd.clear();
    clearData();
  }
}

//interrupt
void coinInterrupt() 
{
  pulse++ ;
  insert = true;
}

void clearData() 
{
  //Reset data_count
  data_count = 0;
  //Reset Data
  Data ="";
}