// For: https://forum.arduino.cc/t/push-button-long-vs-short-press/995531/
//
// Checking used pins at: https://randomnerdtutorials.com/esp32-pinout-reference-gpios/
//   Pin number 12 should not be high at startup.
//     That means a extra external pullup is not allowed and the button might need one.
//   Pin 13 and 33 are okay to use. 
// 
// The button is default HIGH, but lastState is initialized as LOW.
// The if-statements are missing '{' and '}'
//

#define BUTTON_PIN 12 // ESP32 GIOP12 pin connected to button's pin
#define BUZZER_PIN 13 // ESP32 GIOP13 pin connected to buzzer's pin
#define MOTOR_PIN 33 // ESP32 GPIO33 pin connected to vibrator motor pin

// The ESP32 has 16 channels which can generate 16 independent waveforms
// We'll just choose PWM channel 0 here
const int TONE_PWM_CHANNEL = 0;

#define SHORT_PRESS_TIME 500 // 500 milliseconds
#define LONG_PRESS_TIME  3000 // 3000 milliseconds

// Variables will change:
int lastState = LOW;  // the previous state from the input pin
int currentState;     // the current reading from the input pin
unsigned long pressedTime  = 0;
unsigned long releasedTime = 0;

void setup() {
  Serial.begin(9600);
  pinMode(BUTTON_PIN, INPUT_PULLUP); // set ESP32 pin to input pull-up mode
  pinMode(MOTOR_PIN, OUTPUT);
  ledcAttachPin(BUZZER_PIN, TONE_PWM_CHANNEL);
}

void loop() {
  // read the state of the switch/button:
  int currentState = digitalRead(BUTTON_PIN);

  if (lastState == HIGH && currentState == LOW)       // button is pressed
    pressedTime = millis();
  else if (lastState == LOW && currentState == HIGH) { // button is released
    releasedTime = millis();

    long pressDuration = releasedTime - pressedTime;

    if ( pressDuration < SHORT_PRESS_TIME )
      ledcWrite(0, 0);
      digitalWrite(MOTOR_PIN, LOW);
      Serial.println("A short press is detected DO NOT SEND NOTIFICATIONS");

    if ( pressDuration > LONG_PRESS_TIME )
      Serial.println("A long press is detected");
      ledcWriteNote(TONE_PWM_CHANNEL, NOTE_C, 4);
      digitalWrite(MOTOR_PIN, HIGH);
      delay(500);
      } 

  // save the the last state
  lastState = currentState;
}