// Play a file from the SD card in looping mode, from the SD card.
// Example program to demonstrate the use of the MIDFile library
//
// Hardware required:
//  SD card interface - change SD_SELECT for SPI comms

#include <SdFat.h>
#include <MD_MIDIFile.h>

#define DEBUG_ON  true  // set to 1 for MIDI output, 0 for debug output
#define GENERATE_TICKS  1

#define DEBUGS(s)     uart.print(s)
#define DEBUG(s, x)   { uart.print(F(s)); uart.print(x); }
#define DEBUGX(s, x)  { uart.print(F(s)); uart.print(x, HEX); }
#define uart_RATE 115200

#if defined(ARDUINO_ARCH_SAMD)
  #define  SD_SELECT  4
  int pin_out[6] = {13, 11, 10, 9, 6, 5};
#else
  #define  SD_SELECT  4
  int pin_out[6] = {13, 27, 33, 15, 32, 14};
#endif

#define ARRAY_SIZE(a) (sizeof(a)/sizeof(a[0]))

// The files in the tune list should be located on the SD card 
// or an error will occur opening the file and the next in the 
// list will be opened (skips errors).
const char *loopfile = "Music1.mid";  // simple and short file
#if GENERATE_TICKS
  //uint32_t lclBPM = 135;
  #define _lclBPM 90
  uint32_t lclBPM = _lclBPM;
#endif

SdFat	SD;
MD_MIDIFile SMF;
#if defined(ARDUINO_ARCH_SAMD)
  #define uart SerialUSB
#endif

byte state_ = 0;
byte channel_ = 0;
byte intensity_ = 0;

void midiCallback(midi_event *pev)
// Called by the MIDIFile library when a file event needs to be processed
// thru the midi communications interface.
// This callback is set up in the setup() function.
{
  #if DEBUG_ON
    DEBUG("M T", pev->track);
    DEBUG(":  Ch ", pev->channel+1);
    DEBUGS(" Data");
  #endif
  state_ = pev->data[0];
  channel_ = pev->data[1];
  intensity_ = pev->data[2];
  #if DEBUG_ON
    DEBUGX(" ", state_);
    DEBUGX(" ", channel_);
    DEBUGX(" ", intensity_);
    uart.print(" ");
    uart.print((channel_), HEX);
    uart.print(" ");
    uart.print(pin_out[channel_-0x24]);
  #endif
  if (intensity_>0)
    {
      digitalWrite(pin_out[channel_-0x24], HIGH);
      #if DEBUG_ON
        uart.println(" Solenoide ON");
      #endif
    }
  else 
    if (intensity_==0)
      {
        digitalWrite(pin_out[channel_-0x24], LOW);
        #if DEBUG_ON
          uart.println(" Solenoide OFF");
        #endif
      }
}

#if GENERATE_TICKS
uint16_t tickClock(void)
// Check if enough time has passed for a MIDI tick and work out how many!
{
  static uint32_t lastTickCheckTime, lastTickError;
  uint8_t   ticks = 0;

  uint32_t elapsedTime = lastTickError + micros() - lastTickCheckTime;
  uint32_t tickTime = (60 * 1000000L) / (lclBPM * SMF.getTicksPerQuarterNote());  // microseconds per tick
  tickTime = (tickTime * 4) / (SMF.getTimeSignature() & 0xf); // Adjusted for time signature

  if (elapsedTime >= tickTime)
  {
    ticks = elapsedTime/tickTime;
    lastTickError = elapsedTime - (tickTime * ticks);
    lastTickCheckTime = micros();   // save for next round of checks
  }

  return(ticks);
}
#endif

void setup(void)
{
  int  err;
  #if DEBUG_ON
    uart.begin(uart_RATE);
  #endif
  delay(4000);
  #if defined(ARDUINO_ARCH_SAMD)
    analogReadResolution(12);
  #endif
  
  for(int i=0; i<6; i++)
  {
    pinMode(pin_out[i], OUTPUT);
    digitalWrite(pin_out[i], LOW);
  }
  DEBUGS("\n[MidiFile Looper]");

  // Initialize SD
  if (!SD.begin(SD_SELECT, SPI_HALF_SPEED))
  {
    DEBUGS("\nSD init fail!");
    while (true) ;
  }

  // Initialize MIDIFile
  SMF.begin(&SD);
  SMF.setMidiHandler(midiCallback);
  SMF.looping(false);

  // use the next file name and play it
  DEBUG("\nFile: ", loopfile);
  SMF.setFilename(loopfile);
  err = SMF.load(loopfile);
  if (err != MD_MIDIFile::E_OK)
  {
    DEBUG("\nSMF load Error ", err);
    while (true);
  }
}

void loop(void)
{
  //uart.println(analogRead(A0));
  #if GENERATE_TICKS
    static bool fBeat = false;
    static uint16_t sumTicks = 0;
    uint32_t ticks = tickClock();
    lclBPM = map(analogRead(A0), 0, 4095, -(_lclBPM - 30), (_lclBPM - 30)) + _lclBPM;
    #if DEBUG_ON
      //uart.println(lclBPM);
    #endif
    if (ticks > 0)
    {
      SMF.processEvents(ticks);  
//      SMF.isEOF();  // side effect to cause restart at EOF if looping
//      sumTicks += ticks;
//      if (sumTicks >= SMF.getTicksPerQuarterNote())
//      {
//        sumTicks = 0;
//        fBeat = !fBeat;
//      }    
      if(!SMF.isEOF()){  // side effect to cause restart at EOF if looping
        sumTicks += ticks;
        if (sumTicks >= SMF.getTicksPerQuarterNote())
        {
          sumTicks = 0;
          fBeat = !fBeat;
        }}    
    }  
  #else
    // play the file
    if (!SMF.isEOF())
    {
      SMF.getNextEvent();
    }
  #endif*/
}