// Alle pinnen van de leds
const uint8_t ledPins[] = { 9, 11, 10, 6, 3, 5 };

// de pin van de potmeter
byte potPin = A3;
byte switchPin = 12;
// de waarde die de potmeter aangeeft
int potValue;
int switchValue;
bool LED0 = 0;

// geeft de richting aan waar de led moeten draaien.
int richting;

// houdt de index bij van de huidige brandende led
int currentLed = 0;
// houdt de index bij van de leds van de staart
byte trails[5] = {0, 0, 0, 0, 0};

String action;
int oldSwitchValue;


unsigned long previousMillis = 0;
long interval;

void setup() {
  // Zet de seriele monitor aan
  Serial.begin(115200);


  for (uint8_t cnt = 0; cnt < sizeof(ledPins); cnt++) {
    // Zet alle leds uit
    analogWrite(ledPins[cnt], 0);
    // Zet de pin mode op output
    pinMode(ledPins[cnt], OUTPUT);
  }

  pinMode(switchPin, INPUT_PULLUP);
}

void debug(String text, int variable) {
  Serial.print("Mode :");
  Serial.print(action);
  Serial.print('\t');
  Serial.print('\t');
  Serial.print("Led :");
  Serial.print(currentLed);
  Serial.print('\t');
  Serial.print('\t');
  Serial.print(text);
  Serial.print(" : ");
  Serial.print(variable);
  Serial.print('\t');
  Serial.print("Richting");
  Serial.print(" : ");
  Serial.println(richting);

}


void Collect() {
  /**
    Reads the value of the pot meter

    @param values none
    @return void because only a local variable is being changed
  */
  potValue = analogRead(potPin);
  switchValue = digitalRead(switchPin);
}

void reset() {
/**
reset all values to the starting values 
*/
  if (switchValue == 0) {
    currentLed = -1;
  } 

 for (int i = 0; i < 5; i++) {
  trails[i] = 0; 
}

  for (uint8_t cnt = 0; cnt < sizeof(ledPins); cnt++) {
    // Zet alle leds uit
    analogWrite(ledPins[cnt], 0);
  }
  
}



void Process() {
  /**
    Change value of currentled

    Changes the value of some local variables.

    @param values  none
    @return void because only a local variable is being changed
  */


  if (switchValue != oldSwitchValue) {

    
    reset();

    
    oldSwitchValue = switchValue;
  }

    if (switchValue == 0) {
      action = "staart";
      currentLed += richting;
      for (int i = 4; i > 0; i--) {
        trails[i] = trails[i - 1];
      }
    trails[0] = currentLed; 
    }

    if (switchValue == 1) {
      action = "twee_keer";
      LED0 = !LED0;
    }
  

    // Set to predefined values
  richting = 0;
  interval = 5000; 

  // 512 - 30 (middle value - offset)
  if (potValue < 482)  
  {
    // richting wordt linksom
    richting = -1;
    // berekenen van de nieuwe interval voor linksom
    interval = map(potValue, 482, 0, 500, 75);  
  }

  // 512 + 30 (middle value + offset)
  if (potValue > 542) {  

    richting = 1;
    // berekenen van de nieuwe interval voor rechtsom
    interval = map(potValue, 1023, 542, 75, 500);  
  }
  debug("switchValue", switchValue); 
}

void display_leidend() {
  digitalWrite(ledPins[currentLed], LED0);
}

void display_volgend() {

  if (action == "staart") {
    analogWrite(ledPins[trails[4]], 0);
    analogWrite(ledPins[trails[3]], 25);
    analogWrite(ledPins[trails[2]], 54);
    analogWrite(ledPins[trails[1]], 117);
  }

  if (action == "twee_keer") {
    digitalWrite(ledPins[1], LED0);
    digitalWrite(ledPins[2], !LED0);
    digitalWrite(ledPins[3], !LED0);
    digitalWrite(ledPins[4], LED0);
    digitalWrite(ledPins[5], LED0);
  }
}

void Display() {
  /**
    takes care of de display of leds

    @param values  none
    @return void because nothing changes
  */
  display_volgend();
  display_leidend();
}


void preventOverflow() {
  /**
    take care that there is no overflow

    @param values  none
    @return void because only a local variable is being changed
  */


  if (richting == 1) {
    if (action == "staart") {
      if (currentLed >= sizeof(ledPins) - 1) {
        currentLed = -1;
      }
    }
  }

  if (richting == -1) {
    if (action == "staart") {
      if (currentLed <= 0) {
        currentLed = sizeof(ledPins);
      }
    }
  }

}



bool timer() {

  unsigned long currentMillis = millis();

  if (currentMillis - previousMillis >= interval) {
    previousMillis = currentMillis;
    return true;
  }
  return false;
}

void loop() {

  if (timer()) {
    Collect();
    Process();
    Display();
    preventOverflow();
  }
}