// Button handling for IR remotes using Pioneer, NEC, Sony... code
// - These DO NOT send a toggle bit on every new button press, so it is difficult to differ hold and re-pressing
// - On re-pressing this function will send the button again as fast as possible. It uses timers to filter out unintended multi triggering,
//   so this can be a little bit delayed (RC5 and RC6 remotes are better in this case)
// - If a button is held down, the remote will go on sending the same code every 100ms or so.
//   This function will then, after some ignored codes, start with some slow repeats, and then switch to fast repeat rate (with the rate of the incoming codes).

// special case Pioneer Protocol:
// Pioneer Protocol transmits 2 different NEC 32bit codes on each keypress at once
// and always with one repetition, so a short keypress sends 4 NEC codes
// i.E.:
//  NEC, 0xD52A34CB, 32
//  NEC, 0xF50AF708, 32
//  NEC, 0xD52A34CB, 32
//  NEC, 0xF50AF708, 32
// Each pair takes about 184ms -> 368ms for one button press.
// On button hold the same codes are transmitted continuously.
// So the shortest repeat time possible is about every 183ms - but ONLY when the button is held.
// If the button is quickly short pressed it looks just like the same on receiver side.
// As there is always at least 1 repetition, it is mandatory to filter these out, or a single
// button press would always result in 2 events.


uint8_t handleButton_lastSentKey;
unsigned long handleButton_lastSentKey_begin;
unsigned long handleButton_repeatedReceivedMillis;
unsigned long handleButton_repeatMillis;

#define HANDLEBUTTON_FIRST_REPEAT_INTERVAL 500  // minimum ms for the first repeat(s) to trigger an event. the actual value will be slightly more, as it will be only triggert on the next receive from the RC
// so basically it must be a multiple of the time a transmit takes the RC

#define HANDLEBUTTON_SLOW_REPEATS 2                     // how many slow repeats should occur before fast repeats are engaged




#define HANDLEBUTTON_REPEAT_TIMEOUT_0 560         // should be slightly more than 3 transmits of the slowest RC used, so min. 560 for the Pioneer RC
#define HANDLEBUTTON_MAX_REPEATED_RECEIVE_MS_0 200  // slightly more than one transmit, used to detect repetitions
#define HANDLEBUTTON_AVOID_REPEAT_DELAY_0 200     // must be more than one transmits time or repeats could occur also on buttons configured as repeat=false


#define HANDLEBUTTON_REPEAT_TIMEOUT_1 130         // should be slightly more than 3 transmits of the slowest RC used, so min. 560 for the Pioneer RC
#define HANDLEBUTTON_MAX_REPEATED_RECEIVE_MS_1 120  // slightly more than one transmit, used to detect repetitions
#define HANDLEBUTTON_AVOID_REPEAT_DELAY_1 100     // must be more than one transmits time or repeats could occur also on buttons configured as repeat=false


#define HANDLEBUTTON_REPEAT_TIMEOUT_2 120         // should be slightly more than 3 transmits of the slowest RC used, so min. 560 for the Pioneer RC
#define HANDLEBUTTON_MAX_REPEATED_RECEIVE_MS_2 110  // slightly more than one transmit, used to detect repetitions
#define HANDLEBUTTON_AVOID_REPEAT_DELAY_2 100     // must be more than one transmits time or repeats could occur also on buttons configured as repeat=false

unsigned int handleButton_lastKey_countRepeats = 0;



void handleButton(uint8_t _key) {
  handleButton(_key, false, 0);
}

void handleButton(uint8_t _key, bool _repeat) {
  handleButton(_key, _repeat, 0);
}

void handleButton(uint8_t _key, bool _repeat, uint8_t _rcType) {
  // _repeat: enable/disable repeat for this button - if false, holding the button will not trigger repeated events
  // _rcType: 0 = RC code types without toggle bit as in RC5/RC6, therefore a higher delay is required to avoid repeated events at single button presses
  //          1 = other (slower?) remote
  //          2 = ...

  unsigned int _minRepeatInterval = 0;

  if (debug2) {
    Serial.print(F("    loopTime="));
    Serial.print((millis() - lastReceivedMillis));
    Serial.println("ms");
  }
  lastReceivedMillis = millis();

  unsigned int _handleButton_repeat_Timeout, _handleButton_maxRepeatedReceiveMs, _handleButton_avoidRepeatDelay;
  if (_rcType == 1) {
    _handleButton_repeat_Timeout = HANDLEBUTTON_REPEAT_TIMEOUT_1;
    _handleButton_maxRepeatedReceiveMs = HANDLEBUTTON_MAX_REPEATED_RECEIVE_MS_1;
    _handleButton_avoidRepeatDelay = HANDLEBUTTON_AVOID_REPEAT_DELAY_1;
  }
  else if (_rcType == 2) {
    _handleButton_repeat_Timeout = HANDLEBUTTON_REPEAT_TIMEOUT_2;
    _handleButton_maxRepeatedReceiveMs = HANDLEBUTTON_MAX_REPEATED_RECEIVE_MS_2;
    _handleButton_avoidRepeatDelay = HANDLEBUTTON_AVOID_REPEAT_DELAY_2;
  }
  else { // PIONEER o.A.
    _handleButton_repeat_Timeout = HANDLEBUTTON_REPEAT_TIMEOUT_0;
    _handleButton_maxRepeatedReceiveMs = HANDLEBUTTON_MAX_REPEATED_RECEIVE_MS_0;
    _handleButton_avoidRepeatDelay = HANDLEBUTTON_AVOID_REPEAT_DELAY_0;
  }

  if (_repeat) _minRepeatInterval = 1;

  // if this is the POWER button, always use repeat, regardless of function call variable
  if (_key == BTN_POWER) _minRepeatInterval = 1;

  if (_minRepeatInterval > 0) {
    if (handleButton_lastSentKey == _key && (millis() - handleButton_repeatMillis) < _handleButton_repeat_Timeout && (millis() - handleButton_repeatedReceivedMillis) < _handleButton_maxRepeatedReceiveMs) {
      if (debug) {
        Serial.print(F("    R="));
        Serial.print(handleButton_lastKey_countRepeats + 1);
        Serial.print(F(", handleButton_lastSentKey_begin="));
        Serial.print(millis() - handleButton_lastSentKey_begin);
        Serial.print(F("ms, handleButton_repeatMillis="));
        Serial.print(millis() - handleButton_repeatMillis);
        Serial.print(F("ms, handleButton_repeatedReceivedMillis="));
        Serial.print(millis() - handleButton_repeatedReceivedMillis);
        Serial.println(F("ms"));
      }

      if ( (millis() - handleButton_repeatMillis) >= HANDLEBUTTON_FIRST_REPEAT_INTERVAL) {
        // slow repeats
        sendKey(_key);
        if (debug2) {
          Serial.print(F("    SLOW REPEAT  "));
        }
        
        handleButton_repeatMillis = millis();
        handleButton_lastKey_countRepeats++;
      }
      else if ( handleButton_lastKey_countRepeats >= HANDLEBUTTON_SLOW_REPEATS && (millis() - handleButton_repeatMillis) >= _minRepeatInterval) {
        // fast repeats
        sendKey(_key);
        if (debug2) {
          Serial.print(F("    FAST REPEAT  "));
        }
        
        handleButton_repeatMillis = millis();
        handleButton_lastKey_countRepeats++;
      }
      else {
        // waiting to reach HANDLEBUTTON_FIRST_REPEAT_INTERVAL
        //handleButton_repeatMillis = millis();
        if (debug2) {
          Serial.println(F("    REPEAT WAITING  "));
        }
      }
    }
    else {
      // this is the initial button press
      handleButton_lastSentKey_begin = millis();
      handleButton_repeatMillis = millis();
      handleButton_lastSentKey = _key;
      handleButton_lastKey_countRepeats = 0;

      sendKey(_key);
      if (debug2) {
        Serial.print(F("    INITIAL  "));
      }
      if (debug) {
        Serial.print(F("    R="));
        Serial.println(handleButton_lastKey_countRepeats);
      }
    }

    if (handleButton_lastSentKey == _key) {
      handleButton_repeatedReceivedMillis = millis();
      if (debug2) {
        Serial.println(F("    REPRECV  "));
      }
    }
  }
  else if (!_repeat) {
    // only send once
    if ( handleButton_lastSentKey != _key || (handleButton_lastSentKey == _key && (millis() - handleButton_lastSentKey_begin) > _handleButton_avoidRepeatDelay)) {
      sendKey(_key);
      if (debug2) Serial.println(F("    ONCE"));
      //handleButton_lastSentKey_begin = millis();
      handleButton_lastSentKey = _key;
    }
    if (handleButton_lastSentKey == _key) {
      handleButton_lastSentKey_begin = millis();
    }
  }
}