#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27,  16, 2);

void setup() {
  // put your setup code here, to run once:
  lcd.init();
  lcd.backlight();

  //vystupy LED
  pinMode(2, OUTPUT);
  pinMode(3, OUTPUT);
  pinMode(4, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(6, OUTPUT);
  pinMode(7, OUTPUT);
  pinMode(8, OUTPUT);
  pinMode(9, OUTPUT);
   //vstupy tlacidla
  pinMode(10, INPUT_PULLUP);
  pinMode(11, INPUT_PULLUP);
  pinMode(12, INPUT_PULLUP);
  pinMode(13, INPUT_PULLUP);
  pinMode(A0, INPUT_PULLUP);
  pinMode(A1, INPUT_PULLUP);
  pinMode(A2, INPUT_PULLUP);
  pinMode(A3, INPUT_PULLUP);
}

void loop() {
  int start =0, i, stlac=0, skoc=0, level=0, counter=0;
  int tlacidlo[8][2] = {{2,10},{3,11},{4,12},{5,13},{6,14},{7,15},{8,16},{9,17}};
  unsigned long casStart=0, casStop;
  float sec=0, casMin=0, casMax=0, timer=0;

  bool a=1;
  
  lcd.clear();
  lcd.print(" STLAC TLACIDLA");
  lcd.setCursor(0,1);
  lcd.print(" PRE  SPUSTENIE");

  do{
    digitalWrite(2, a);
    digitalWrite(3, a);
    delay(400);
    a=!a;
    if((digitalRead(10)==LOW)&&(digitalRead(11)==LOW))start=1;
  }while(start!=1);
  digitalWrite(2, LOW);
  digitalWrite(3, LOW);
  lcd.clear();
 
  do{
    
    if(counter==10&&level<8){
      level++;
      counter=0;
    }
    i = random(8);
    
    lcd.setCursor(8,0);
    lcd.print("min:");
    lcd.print(casMin/1000);
    lcd.setCursor(8,1);
    lcd.print("max:");
    lcd.print(casMax/1000);

    lcd.setCursor(0,0);
    lcd.print("REAKCIA");

    delay(random(50,(2000-(level*200))));

    digitalWrite(tlacidlo[i][0], HIGH);
    delay(20);
    casStart = millis();
    do{
      stlac = digitalRead(tlacidlo[i][1]);
      timer = millis() - casStart;
      lcd.setCursor(0,1);
      lcd.print(timer/1000);
      if(timer>(10000-(level*2000))){
        skoc=1;
        stlac=0;
      }
    }while(stlac!=0);

    casStop = millis() - casStart;
    sec = casStop;
    lcd.setCursor(0,1);
    lcd.print(sec/1000);
    digitalWrite(tlacidlo[i][0], LOW);
    if(casMin > casStop||casMin==0) casMin = casStop;
    if(casMax < casStop) casMax = casStop;
   
    counter++; 
  }while(skoc!=1);

 do{
    lcd.setCursor(0,0);   
    if(a==HIGH)lcd.print("KONIEC ");
    else lcd.print("       ");
    digitalWrite(9, a);
    delay(400);
    a=!a;
  }while(digitalRead(17)!=LOW);
  digitalWrite(9, LOW);
}