#include <LiquidCrystal.h>
#include <Keypad.h>
//used pind - digital 3,4,5,6,7,8,9,22,23,24,26,28,30,32
//Defining Numpad Configuration
const byte KEYPAD_ROWS = 4;
const byte KEYPAD_COLS = 4;

char keys[KEYPAD_ROWS][KEYPAD_COLS] = {
  {'1', '2', '3', 'A'},
  {'4', '5', '6', 'B'},
  {'7', '8', '9', 'C'},
  {'.', '0', '#', 'D'}
};

byte rowPins[KEYPAD_ROWS] = {9, 8, 7, 6};
byte colPins[KEYPAD_COLS] = {5, 4, 3, 2};

Keypad customKeypad = Keypad(makeKeymap(keys), rowPins, colPins, KEYPAD_ROWS, KEYPAD_COLS);
// Defining the LCD library with arduino pins for related lcd pins
const int rs = 22, en = 24, d4 = 26, d5 = 28, d6 = 30, d7 = 32;
LiquidCrystal lcd(rs, en, d4, d5, d6, d7);

//Definign Digital Meter read output pin
int meter_pin = 23;

//Defining domestic circuit pins arduino

int Light_Bulb_Room = 31;
int Fan_Room = 33;
int Meter_output=0;

//PIR sensor 

int ledPin = 11;                // choose the pin for the LED
int inputPin = 10;               // choose the input pin (for PIR sensor)
int pirState = LOW;             // we start, assuming no motion detected
int val = 0;                    // variable for reading the pin status


//ldr
int LDR_PIN=25;
int Outdoor_light_pin=27;
int LDRState = 0; // this is to identify the change of state of the LDR detected light

//other
int lcd_message_type = 0; // this ditermines what should be printed on the lcd at the moment
String keypad_input;
String unit_charge[4]={"42","50","75","10000"};
int bill_amount=0;



void setup() {

  Serial.begin(9600);


  for (int pin_no=3;pin_no<10;pin_no++){
      pinMode(pin_no,OUTPUT);
  }
  for (int pin_no=22;pin_no<33;pin_no=pin_no+2){
      pinMode(pin_no,OUTPUT);
  }
  pinMode(meter_pin, INPUT);
  digitalWrite(meter_pin,LOW);

  pinMode(Light_Bulb_Room,OUTPUT);
  pinMode(Fan_Room,OUTPUT);
  pinMode(ledPin, OUTPUT);      
  pinMode(inputPin, INPUT);     
  pinMode(LDR_PIN, INPUT);

  // set up the LCD's number of columns and rows:
  lcd.begin(16, 2);
  // Print a message to the LCD.
  lcd.print("Hello");

}



void loop() {
  // set the cursor to column 0, line 1
  // (note: line 1 is the second row, since counting begins with 0):

  Meter_output+=digitalRead(meter_pin);
  bill_amount_func(Meter_output);

  if (bill_amount>unit_charge[3].toInt()){
    lcd_message_type = 3;
  }
  
//keypad starts...................

  char customKey = customKeypad.getKey();
  if (customKey){
    tariff(customKey, unit_charge);
  }

  //The process of PIR sensor in the below codes

  val = digitalRead(inputPin);  // read input value
  if (val == HIGH) {            // check if the input is HIGH
    digitalWrite(ledPin, HIGH);  // turn LED ON
    if (pirState == LOW) {
      // we have just turned on

        digitalWrite(Light_Bulb_Room,HIGH);//turn on the light
        digitalWrite(Light_Bulb_Room,LOW);//turn on the Fan
        
        lcd_message_type = 1;

      // We only want to print on the output change, not state
      pirState = HIGH;
    }
  } else {

    digitalWrite(ledPin, LOW); // turn LED OFF

    if (pirState == HIGH) {
      // we have just turned of
      lcd_message_type = 2;
      // We only want to print on the output change, not state
      pirState = LOW;
    }
  }

  if (digitalRead(LDR_PIN) == LOW) {
    digitalWrite(Outdoor_light_pin, LOW);
    if (LDRState==1){
     lcd_message_type=5;
    }



  } else {
    digitalWrite(Outdoor_light_pin, HIGH);
    if (LDRState==0){
     lcd_message_type=4;
    }




  }


  //lcd print
  

  if (lcd_message_type==0){
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("Meter");
      lcd.setCursor(6,0);
      lcd.print(Meter_output);
      lcd.setCursor(0,1);
      lcd.print("Bill");
      lcd.setCursor(5,1);
      lcd.print(bill_amount);

  }
  else if(lcd_message_type==1){
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("Motion detected!");
        lcd.setCursor(0, 1);
        lcd.print("Light On");
        delay(3000);
        lcd_message_type = 0;
  }

  else if(lcd_message_type==2){
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("Motion ended!");
        lcd.setCursor(0, 1);
        lcd.print("Light Off");
        delay(3000);
        lcd_message_type = 0;
  }
    else if(lcd_message_type==3){
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("Red Notice");
        lcd.setCursor(0, 1);
        lcd.print("Bill Max Exceeded");
    }
    else if(lcd_message_type==4){
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("LDR Detected");
      lcd.setCursor(0,1);
      lcd.print("Light ON");
      delay(2000);
      LDRState=1;
      lcd_message_type=0;
    }
    else if(lcd_message_type==5){
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("LDR Detected");
      lcd.setCursor(0,1);
      lcd.print("Light OFF");
      delay(2000);
      LDRState=0;
      lcd_message_type=0;
    }

delay(100); //to reduce the lcd blinking
}






void tariff(char Letter, String Unit_Charge_Array[]){

  if (Letter=='A'){

    char key=customKeypad.getKey();
    while(key!='#'){
      if(key){
        keypad_input+=key;
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("A");
        lcd.setCursor(0, 1);
        lcd.print(keypad_input);
        Unit_Charge_Array[0]=keypad_input;
      }

      key=customKeypad.getKey();

    }
    keypad_input="";
    lcd_message_type = 0;
  }
  else if (Letter=='B'){
    char key=customKeypad.getKey();
    while(key!='#'){
      if(key){
        keypad_input+=key;
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("B");
        lcd.setCursor(0, 1);
        lcd.print(keypad_input);
        Unit_Charge_Array[1]=keypad_input;
      }

      key=customKeypad.getKey();

    }
    keypad_input="";
    lcd_message_type = 0;
  }
  else if (Letter=='C'){
     char key=customKeypad.getKey();
    while(key!='#'){
      if(key){
        keypad_input+=key;
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("C");
        lcd.setCursor(0, 1);
        lcd.print(keypad_input);
        Unit_Charge_Array[2]=keypad_input;
      }

      key=customKeypad.getKey();

    }
    keypad_input="";
    lcd_message_type = 0;
  }
    else if (Letter=='D'){
     char key=customKeypad.getKey();
    while(key!='#'){
      if(key){
        keypad_input+=key;
        lcd.clear();
        lcd.setCursor(0, 0);
        lcd.print("D");
        lcd.setCursor(0, 1);
        lcd.print(keypad_input);
        Unit_Charge_Array[3]=keypad_input;
      }

      key=customKeypad.getKey();

    }
    keypad_input="";
    lcd_message_type = 0;
  }

}

void bill_amount_func(int Meter_Reading){
  if (Meter_Reading>120){
    bill_amount=(Meter_Reading-120)* (unit_charge[2].toInt());
    bill_amount+=(120-60)*(unit_charge[1].toInt());
    bill_amount+=(60-0)*(unit_charge[0].toInt());

  }

  else if (Meter_Reading>60){

    bill_amount=(Meter_Reading-60)*(unit_charge[1].toInt());
    bill_amount+=(60-0)*(unit_charge[0].toInt());

  }
  else{
    bill_amount=(Meter_Reading)*(unit_charge[0].toInt());
  }

}