const int button_pins_array[] = {7, 6, 5, 4};
const int led_pins_array[] = {8, 9, 10, 11};
int button_state_array[4];
unsigned long time_from_start = 0;
unsigned long time_passed = 0;
int blink_time = 300;
int blink_time_increment = 100;

int brightness = 0;  // how bright the LED is
int fade_amount = 5;  // how many points to fade the LED by


void handle_button_states() {
  // Read button states and invert logic (active low)
  for (int i = 0; i < 4; i++) {
    button_state_array[i] = !digitalRead(button_pins_array[i]);
  }
}

void change_blink_frequency() {
  if (button_state_array[1] == HIGH) {
    blink_time += blink_time_increment;

    delay(200); // Short delay to debounce button press
    Serial.println(blink_time);
  }
  else if (( button_state_array[2] == HIGH ) && ( blink_time >= blink_time_increment )) {
    blink_time -= blink_time_increment;

    delay(200); // Short delay to debounce button press
    Serial.println(blink_time);
  }
}

void blink_led(int pin_number) {
  time_from_start = millis();

  if((time_from_start - time_passed) > blink_time) {
    time_passed = time_from_start;
    if (digitalRead(pin_number) == LOW) {
      digitalWrite(pin_number, HIGH);
    }
    else {
      digitalWrite(pin_number, LOW);
    }
  }
}

void change_fade_amount() {
  if (button_state_array[2] == HIGH) {
    void dimming_led(led_pins_array[2]);

    delay(200); // Short delay to debounce button press
    Serial.println(blink_time);
  }
  else if (( button_state_array[2] == HIGH ) && ( blink_time >= blink_time_increment )) {
    blink_time -= blink_time_increment;

    delay(200); // Short delay to debounce button press
    Serial.println(blink_time);
  }
}

int dimming_led(int pin_number) {

    // set the brightness of the pin 
    analogWrite(pin_number, brightness);

    // change the brightness for next time through the loop:
    brightness = brightness + fade_amount;

    // reverse the direction of the fading at the ends of the fade:
    if (brightness <= 0 || brightness >= 255) {
      fade_amount = -fade_amount;
    }
    // wait for 30 milliseconds to see the dimming effect
    //delay(30);
  }












void outputs() {
  if ((button_state_array[0] == HIGH)) {
    digitalWrite(led_pins_array[0], HIGH);
  }
  else {
    digitalWrite(led_pins_array[0], LOW);
  }
}


void setup() {
  Serial.begin(9600);
  // Initialize button pins as input with pull-up resistors
  for (int i = 0; i < 4; i++) {
    pinMode(button_pins_array[i], INPUT_PULLUP);
  }
  // Initialize LED pins as output
  for (int i = 0; i < 4; i++) {
    pinMode(led_pins_array[i], OUTPUT);
  }
}

void loop() {
  handle_button_states();
  blink_led(led_pins_array[1]);
  void change_fade_amount()
  change_blink_frequency();
  outputs();
}