Four buttons four LEDs

/*
  18 July 2018

  Four buttons four LEDs

  Problem 1: LED1 needs to be on only when button1 is held down.
  Right now it takes several presses to turn on and off and stays on.
  Problem 1: LEDs 2,3,4 do not turn off with buttons 2,3,4.
  They are all turned off by button1, which is what I want, but I also
  need them to turn of with their respective button presses.
*/

// set pins
const int buttonPin1 = 2;                 // Pin1's pushbutton
const int buttonPin2 = 4;                 // Pin2's pushbutton
const int buttonPin3 = 6;                 // Pin3's pushbutton
const int buttonPin4 = 8;                 // Pin4's pushbutton
const int ledPin1 = 3;                    // Pin1's LED
const int ledPin2 = 5;                    // Pin2's LED
const int ledPin3 = 7;                    // Pin3's LED
const int ledPin4 = 9;                    // Pin4's LED

// set variables
int ledPin1_status = 0;
int ledPin1_previousStatus = 0; // If you want to detect a change of a pin value, then you should store the previous value AND the current value.
// The previous value is used to compare to the current value, and then (if the two are different) the current value is used to change the PED pin status.
int ledPin2_status = 0;
int ledPin3_status = 0;
int ledPin4_status = 0;

void setup() {  //initialize pins
  pinMode(buttonPin1, INPUT); // set PINn as INPUT
  pinMode(buttonPin2, INPUT);
  pinMode(buttonPin3, INPUT);
  pinMode(buttonPin4, INPUT);
  pinMode(ledPin1, OUTPUT);   // set LEDn as OUTPUT
  pinMode(ledPin2, OUTPUT);
  pinMode(ledPin3, OUTPUT);
  pinMode(ledPin4, OUTPUT);
}

/*
   There is different ways of debouncing buttons, below is just the way I prefer to do it.
*/
unsigned long previousButtonPressTime = 0;  // the last time the output pin was toggled
unsigned long currentButtonPressTime = 0;    // the debounce time; increase if the output flickers
unsigned long buttonDebounceDelay = 100; // the button debounce time in milliseconds
bool buttonsEnabled = true; // This is used for disabling all the buttons during debouncing


// function prototypes -- not strictly needed here but declaring functions is a good habit to aquire
void turnOffLEDs234();
void switchLED(int, int);
void disableButtons();


void loop() {

  ledPin1_status = digitalRead(buttonPin1);
  if (ledPin1_status != ledPin1_previousStatus) {
    if (ledPin1_status == 1) {
      if (buttonsEnabled == true) {
        switchLED(1, ledPin1_status);
        ledPin1_previousStatus = ledPin1_status; // This line is here is to make sure that this code section only runs when the ledPin1_status changes.
        disableButtons(); // This starts the button debounce timer and disables the buttons.
        // If you wanted LEDs 2,3 and 4 to turn off when button 1 was pressed down, then you would un-comment the line below:
        turnOffLEDs234();
        // You can also have LEDs 2-3-4 turn off when button 1 is released. That line is #76 further below.
      }
    }
    else { // if (ledPin1_status == 0)
      switchLED(1, ledPin1_status);
      ledPin1_previousStatus = ledPin1_status; // This line is here is to make sure that this code section only runs when the ledPin1_status changes.
      // If you wanted LEDs 2,3 and 4 to turn off when button 1 was released, then you would use the line below:
      //turnOffLEDs234();
    }
  }


  if (buttonsEnabled == true) {
    ledPin2_status = digitalRead(buttonPin2);
    if (ledPin2_status == HIGH) {
      switchLED(2, ledPin2_status);
      disableButtons();
    }

    ledPin3_status = digitalRead(buttonPin3);
    if (ledPin3_status == HIGH) {
      switchLED(3, ledPin3_status);
      disableButtons();
    }

    ledPin4_status = digitalRead(buttonPin4);
    if (ledPin4_status == HIGH) {
      switchLED(4, ledPin4_status);
      disableButtons();
    }
  }
  else { // if (buttonsEnabled == false)
    // Below is checking for the de-bounce time and re-enabling the buttons:
    currentButtonPressTime = millis();
    if (currentButtonPressTime >= previousButtonPressTime) {
      if (currentButtonPressTime >= (previousButtonPressTime + buttonDebounceDelay)) {
        buttonsEnabled = true; // This re-enables the buttons
      }
    }
    else {
      previousButtonPressTime = millis(); // rollover condition
    }
  }

} // ----------- end of main program loop



void turnOffLEDs234() {
  // This is just a convenient way to turn off all three LEDs at once.
  // This only turns LEDs 2-3-4 off, as they get turned on individually by their own buttons.
  ledPin2_status = 0;
  switchLED(2, ledPin2_status);
  ledPin3_status = 0;
  switchLED(3, ledPin3_status);
  ledPin4_status = 0;
  switchLED(4, ledPin4_status);
}



void switchLED(int LEDnum, int LEDstate) {
  // This function writes the given LED to the given state.
  // All the LEDs are always changed using this one function.
  switch (LEDnum) {
    case 1:
      digitalWrite(ledPin1, LEDstate);
      break;
    case 2:
      digitalWrite(ledPin2, LEDstate);
      break;
    case 3:
      digitalWrite(ledPin3, LEDstate);
      break;
    case 4:
      digitalWrite(ledPin4, LEDstate);
      break;
      //default:
      // statements
  }
}



void disableButtons() {
  // This disables all the buttons until the debounce time passes.
  previousButtonPressTime = millis();
  buttonsEnabled = false;
}