#include <EasyButton.h>

#define maxLeds 4
const int ledPins[maxLeds] = {25,26,27,14};
const int btnPins[maxLeds] = {5,4,2,15};
const bool PullupTrue = true;
const bool InvertTrue = true;
const int debounceTimer = 35;

volatile int ledOnTime[maxLeds] = {3,3,3,3};
volatile int ledTriggerTime[maxLeds] = {1,2,3,4};
volatile boolean ledQueue[maxLeds] = {true,true,true,true};
volatile long previousTime[maxLeds] = {0,0,0,0};
long previousM = 0;
volatile int activeLed = maxLeds;
boolean timerStarted = false;

const int sec = 1000;

int turnOnNextLed = true;

EasyButton RedButton(btnPins[0],debounceTimer,PullupTrue,InvertTrue);
EasyButton GreenButton(btnPins[1],debounceTimer,PullupTrue,InvertTrue);
EasyButton BlueButton(btnPins[2],debounceTimer,PullupTrue,InvertTrue);
EasyButton YellowButton(btnPins[3],debounceTimer,PullupTrue,InvertTrue);

void setup() {
  // put your setup code here, to run once:
  Serial.begin(115200);
  Serial.println("Hello, ESP32!");

 for(int thisPin = 0; thisPin < maxLeds;thisPin++){
  pinMode(ledPins[thisPin], OUTPUT);
  digitalWrite(ledPins[thisPin], LOW);
 }

  RedButton.begin();
  RedButton.onPressed(RedBtnPressed);
  RedButton.enableInterrupt(RedBtnCall);

  GreenButton.begin();
  GreenButton.onPressed(GreenBtnPressed);
  GreenButton.enableInterrupt(GreenBtnCall);

  BlueButton.begin();
  BlueButton.onPressed(BlueBtnPressed);
  BlueButton.enableInterrupt(BlueBtnCall);

  YellowButton.begin();
  YellowButton.onPressed(YellowBtnPressed);
  YellowButton.enableInterrupt(YellowBtnCall);
}
///////////////////////////////////Button Interrupt Callbacks
void loop() {
  RedButton.update();
  GreenButton.update();
  BlueButton.update();
  YellowButton.update();

  QueueNextLed();

  for(int thisLed = 0; thisLed < maxLeds;thisLed++){
    if(thisLed == activeLed){
      LedTimerFunction(thisLed);
    }
  }
  
}
void RedBtnCall(){
  RedButton.read();
}
void GreenBtnCall(){
  GreenButton.read();
}
void BlueBtnCall(){
  BlueButton.read();
}
void YellowBtnCall(){
  YellowButton.read();
}
/////////////////////////////////////Buttons pressed funtions
void RedBtnPressed(){
    ledQueue[0] = true;
}
void GreenBtnPressed(){
    ledQueue[1] = true;
}
void BlueBtnPressed(){
    ledQueue[2] = true;
}
void YellowBtnPressed(){
    ledQueue[3] = true;
}

void QueueNextLed(){
  if(turnOnNextLed){
    int counter = 0;
    for(int thisLed = 0;thisLed < maxLeds;thisLed++){
      if(ledQueue[thisLed]){
        activeLed = thisLed;
        turnOnNextLed = false;
        break;
      }
      else{
        counter++;
      }
    }
    if(counter >= maxLeds){
      activeLed = maxLeds;
    }
  }
}
void LedTimerFunction (int ledNum){   

  if(timerStarted == false && turnOnNextLed == false){
    digitalWrite(ledPins[ledNum], HIGH);
    timerStarted = true;
    //previousTime[ledNum] = millis();
    previousM = millis();
    Serial.println("Timer started for LED " + String(ledNum));
  }
  
  if (((long)millis() - previousM) >= (ledOnTime[ledNum] * sec)){
    Serial.println("Time completed = "+ String((long)millis() - previousM));
    digitalWrite(ledPins[ledNum], LOW);
    ledQueue[ledNum] = false;
    activeLed = maxLeds;
    //previousTime[ledNum] = millis();
    previousM = millis();
    turnOnNextLed = true;
    timerStarted = false;
    Serial.println("Timer completed for LED " + String(ledNum));    
  }
 }