#include <Keypad.h>
#include <LiquidCrystal_I2C.h> //library for I2c LCD
#define I2C_ADDR    0x27 

/* ======== USER SETTINGS =========== */
// special effects
#define ENABLE_TICK_SOUND        true

// Define other pin connections
#define  UP_BUTTON 2
#define DOWN_BUTTON 3
#define BUZZER  4

int armCode = 1234;
int disarmCode = 4567;
int duration=30;      // Duration in seconds

int isArmed=0, enteredVal=0, instant_detonation=0;
String dispString="";

const byte ROWS = 4, COLS = 3; //four rows, three columns

char keys[ROWS][COLS] = {
  {'1', '2', '3'},
  {'4', '5', '6'},
  {'7', '8', '9'},
  {'*', '0', '#'}
};
byte rowPins[ROWS] = {8, 7, 6, 5}; //connect to the row pinouts of the keypad
byte colPins[COLS] = {A3, A2, A1}; //connect to the column pinouts of the keypad

//Create an object of keypad
Keypad keypad = Keypad( makeKeymap(keys), rowPins, colPins, ROWS, COLS );


/*initializing 16x2 LCD at the pre defined I2C address */
LiquidCrystal_I2C lcd(I2C_ADDR, 16, 2);


void  setup() {
  Serial.begin(9600);
  pinMode(UP_BUTTON, INPUT_PULLUP);
  pinMode(DOWN_BUTTON, INPUT_PULLUP);
  pinMode(BUZZER, OUTPUT);

  lcd.init();
  lcd.backlight();
  lcd.clear();
  ShowTime(duration);
}

void loop() {
  char key = keypad.getKey();// Read the key
  // Function will checks for time change buttons and only return
  // when  start button pressed
  if(isArmed==0) WaitForStart(key);
  // Start the duration timer
  if(isArmed==1) TimeDuration(key);
}


void  WaitForStart(char key) {
    if (digitalRead(UP_BUTTON) == LOW) {
      if (duration  < 60) duration++;
      else duration +=  10;
      ShowTime(duration);
      delay(250);
    }
    if (digitalRead(DOWN_BUTTON)  == LOW) {
      if (duration > 60) duration -= 10;
      else if(duration > 0) duration--;
      ShowTime(duration);
      delay(250);
    }
    if ((key - '0' >= 0) && (key - '0' <= 9)) {
      lcd.clear();
      enteredVal = (enteredVal * 10) + (key - '0');
      dispString += "*";
      lcd.setCursor(6, 0); lcd.print(dispString);
      if(dispString.length()>=4){
        
        if(enteredVal== armCode) {
          isArmed = 1;
          tone(BUZZER,  1200, 550);
          lcd.clear();
          lcd.print("   Bomb Armed   ");
          delay(1000);
          lcd.clear();
        }
        else{
          lcd.clear();
          lcd.print("  Invalid Code  ");
          tone(BUZZER,  600, 250);
          delay(3000);
          lcd.clear();
        }
        dispString="";
        enteredVal=0;
        ShowTime(duration);
      }
    }
}


void  TimeDuration(char key) {
  // While loop will continue until time up
  unsigned long  startTime = millis(), oneSecStartTime = millis();
  unsigned long timer = 1000ul * duration;
  // Repeatedly  check if time is up
  while (isArmed && !instant_detonation && ((millis() - startTime) <= timer)) {
    // Calculate  time elapsed in seconds
    int elapsed = int((millis() - startTime) / 1000);
    // Only start to display countdown after 3 seconds
    if ((millis() - oneSecStartTime)  >= 1000) {
      ShowTime(duration - elapsed);
      tone(BUZZER, 1300, 150);
      oneSecStartTime=millis();
    }

  key = keypad.getKey();
  if ((key - '0' >= 0) && (key - '0' <= 9)) {
      lcd.clear();
      enteredVal = (enteredVal * 10) + (key - '0');
      dispString += "*";
      lcd.setCursor(6, 0); lcd.print(dispString);
      if(dispString.length()>=4){
        
        if(enteredVal== disarmCode) {
          isArmed = 0;
          tone(BUZZER,  1200, 550);
          lcd.clear();
          lcd.print(" Bomb Disarmed  ");
          delay(1000);
          lcd.clear();
        }
        else{
          lcd.clear();
          lcd.print("  Invalid Code  ");
          lcd.setCursor(0,1);
          lcd.print("Bomb Detonating");
          tone(BUZZER,  600, 250);
          delay(3000);
          instant_detonation=1;
          lcd.clear();
        }
        dispString="";
        enteredVal=0;
        ShowTime(duration);
      }
    }
  }

if(isArmed){
  lcd.clear();
  if(!instant_detonation) lcd.print("   Time is Up   ");

  // Time up
  tone(BUZZER, 250, 500);
  delay(500);
  tone(BUZZER, 125, 500);
  delay(500);
  tone(BUZZER, 250, 500);
  delay(500);
  tone(BUZZER, 125, 500);
  delay(500);
  tone(BUZZER, 250, 500);
  delay(500);
  tone(BUZZER, 125, 500);
  delay(500);
  tone(BUZZER, 250, 500);
}

  //display.clear();
  //display.setSegments(seg_end);
  // Wait 5 seconds and reset display
  delay(5000);
  // Show duration for  next player
  isArmed=0;
  instant_detonation=0;
  ShowTime(duration);
}


void ShowTime(int value) {
  
  static  int lastTime;
  // Update the display if time has changed
  if (1){//lastTime !=  value) {
    lastTime = value;
    int iMinutes = value / 60;
    int iSeconds  = value - (iMinutes * 60);

    // Show on LCD display
    lcd.setCursor(6,1);
    if(iMinutes<10) lcd.print("0");
    lcd.print(iMinutes);

    lcd.print(":");

    if(iSeconds<10) lcd.print("0");
    lcd.print(iSeconds);

    lcd.setCursor(0,0);
    if(isArmed) lcd.print("   Bomb Armed   ");
    else lcd.print("    Not Armed   ");
  }
}