doorbell example has false positives

First, thanks for writing this, it has made hooking up my doorbell to alexa/google-home really easy.

I started with the doorbell example, but it had a habit of being too sensitive and generated false positives. The following code will trigger an event at the slightest provocation:

https://github.com/sinricpro/esp8266-esp32-sdk/blob/246c363f8bb439f137fbe53162f7a334e298994f/examples/doorbell/doorbell.ino#L54-L55

I ended up rewriting it to make sure the button was pressed for at least 25ms before triggering the event. This is the code I ended up with (note that the pin mode for the button is set to INPUT_PULLUP):

enum class ButtonState {
  on,
  off,
};

// checkButtonpress
// reads if BUTTON_PIN gets LOW and send Event
void checkButtonPress() {
  static std::optional<unsigned long> firstBtnLow;
  static std::optional<unsigned long> firstBtnHigh;
  static ButtonState buttonState = ButtonState::off;
  unsigned long actualMillis = millis();
  auto buttonPinValue = digitalRead(BUTTON_PIN);

  if (buttonState == ButtonState::on) {
    if (buttonPinValue == HIGH) {
      if (!firstBtnHigh) {
        firstBtnHigh = actualMillis;
      } else {
        if (actualMillis - firstBtnHigh.value() > 25) {
          buttonState = ButtonState::off;
          firstBtnHigh = std::nullopt;
          firstBtnLow = std::nullopt;
        }
      }
    } else {
      firstBtnHigh = std::nullopt;
    }
  } else if (buttonPinValue == LOW) {
    if (!firstBtnLow) {
      firstBtnLow = actualMillis;
    } else {
      if (actualMillis - firstBtnLow.value() > 25) {
        firstBtnHigh = std::nullopt;
        firstBtnLow = std::nullopt;
        buttonState = ButtonState::on;
        Serial.printf("Ding dong...\r\n");
        // get Doorbell device back
        SinricProDoorbell& myDoorbell = SinricPro[DOORBELL_ID];

        // send doorbell event
        myDoorbell.sendDoorbellEvent();
      }
    }
  } else {
    firstBtnLow = std::nullopt;
  }
}

This code is much closer to what is generated for a button in esphome.

sinricpro / esp8266-esp32-sdk

doorbell example has false positives #346