#include <LiquidCrystal_I2C.h>
#include <Wire.h>
LiquidCrystal_I2C lcd(0x27, 16, 2);
#define start_T 1000
#define bull_T 200
#define mx 800
#define mn 200
#define mxb 12
#define mxc 5
int cnt = 0;
int bullets = mxb;
long tm, gtm;
bool game = false;
byte sqr[8] = {
  B11111,
  B11111,
  B11111,
  B11111,
  B11111,
  B11111,
  B11111,
  B11111
};
class timer{
  private:
  long tmr, dtmr;
  bool flag;
  public:
  timer(){
    tmr = 0;
  }
  void zero_t(){
    flag = false;
    tmr = 0;
  }
  void start_t(){
    flag = true;
    dtmr = millis() - tmr;
  }
  void stop_t(){
    flag = false;
    tmr = millis() - dtmr;
  }
  long get_t(){
    return (flag ? millis() - dtmr : tmr);
  }
};
timer tmr;
void setup() {
  lcd.init();
  lcd.backlight();
  lcd.createChar(0, sqr);
  pinMode(12, OUTPUT);
  pinMode(2, INPUT_PULLUP);
  pinMode(3, INPUT_PULLUP);

  //общение с мишенью
  pinMode(6, INPUT);
  pinMode(13, OUTPUT);
  
  pinMode(11, INPUT_PULLUP);
  pinMode(14, INPUT);
  attachInterrupt(0, push, FALLING);
  attachInterrupt(1, pull, RISING);
  digitalWrite(13, LOW);
}

void loop() {
  while(digitalRead(11) && !game){}
  game = true;
  for(int i = 3; i >= 0; i--){
    lcd.clear();
    if(i) lcd.print(i);
    else lcd.print("Start!..");
    delay(start_T);

  }
  lcd.clear();
  gtm = millis();
  for(int i = 0; i < bullets; i++) lcd.write(0); 
  tm = tmr.get_t();
  while(game){
    if(tmr.get_t() - tm > bull_T){
      tm = tmr.get_t();
      bullets--;
      lcd.scrollDisplayLeft();
    }
    if(digitalRead(6)){
      game = false;
      lcd.clear();
      lcd.print("Easy Win in ");
      lcd.setCursor(0, 1);
      long tmp = millis() - gtm;
      lcd.print(tmp/1000);
      lcd.print(".");
      lcd.print(tmp%1000);
      lcd.print(" seconds!");
      delay(3000);
    }
    if(!bullets){
      while(analogRead(14) < mx){}
      while(analogRead(14) > mn){}
      bullets = mxb; lcd.clear();
      cnt++;
      if(cnt == mxc){
        lcd.print("Bullets off!");
        digitalWrite(13, HIGH);
        delay(200);
        digitalWrite(13, LOW);
        game = false;
        break;
      }
      for(int i = 0; i < bullets; i++)lcd.write(0);
      tm = tmr.get_t();
    }
  }

}
void push(){
  if(bullets){ digitalWrite(12, HIGH);}
  tmr.start_t();
  
}
void pull(){
  digitalWrite(12, LOW);
  tmr.stop_t();
}