void _MidiInProc(IntPtr handle, int msg, int instance, int lparam, int wparam)
{
switch (msg)
{
case MIM_OPEN:
Opened?.Invoke(this, EventArgs.Empty);
break;
case MIM_CLOSE:
Closed?.Invoke(this, EventArgs.Empty);
break;
case MIM_DATA:
MidiMessage m;
if (0 != _tempoSynchEnabled && 0xF8 == (0xFF & lparam))
{
if (0 != _timingTimestamp)
{
var dif = (_PreciseUtcNowTicks - _timingTimestamp) * 24;
var tpm = TimeSpan.TicksPerMillisecond * 60000;
var newTempo = (tpm / (double)dif);
if (newTempo < _tempoSynchMininumTempo)
{
Interlocked.Exchange(ref _timingTimestamp, 0);
}
else
{
var timeNow = _PreciseUtcNowTicks;
if (0L == _tempoSyncTimestamp || 0L == _tempoSyncFrequency || (timeNow - _tempoSyncTimestamp > _tempoSyncFrequency))
{
var tmp = Tempo;
var ta = (tmp + newTempo) / 2;
Tempo = ta;
}
Interlocked.Exchange(ref _timingTimestamp, timeNow);
}
}
else
{
var timeNow = _PreciseUtcNowTicks;
Interlocked.Exchange(ref _timingTimestamp, timeNow);
}
}
else
{
m = MidiUtility.UnpackMessage(lparam);
_ProcessRecording(m);
Input?.Invoke(this, new MidiInputEventArgs(new TimeSpan(0, 0, 0, 0, wparam), m));
}
break;
case MIM_ERROR:
Error?.Invoke(this, new MidiInputEventArgs(new TimeSpan(0, 0, 0, 0, wparam), MidiUtility.UnpackMessage(lparam)));
break;
case MIM_LONGDATA:
case MIM_LONGERROR:
// TODO: Semi tested
var hdr = (MIDIHDR)Marshal.PtrToStructure(new IntPtr(lparam), typeof(MIDIHDR));
if (0 == hdr.dwBytesRecorded)
{
return; // no message
}
// this code assumes it's a sysex message but I should probably check it.
var status = Marshal.ReadByte(hdr.lpData, 0);
var payload = new byte[hdr.dwBytesRecorded - 1];
Marshal.Copy(new IntPtr((int)hdr.lpData + 1), payload, 0, payload.Length);
m = new MidiMessageSysex(payload);
var sz = Marshal.SizeOf(typeof(MIDIHDR));
_inHeader.dwBufferLength = _inHeader.dwBytesRecorded = 65536u;
_inHeader.lpData = _buffer;
_CheckInResult(midiInPrepareHeader(_handle, ref _inHeader, sz));
_CheckInResult(midiInAddBuffer(_handle, ref _inHeader, sz));
_ProcessRecording(m);
if (MIM_LONGDATA == msg)
{
Input?.Invoke(this, new MidiInputEventArgs(new TimeSpan(0, 0, 0, 0, wparam), m));
}
else
{
Error?.Invoke(this, new MidiInputEventArgs(new TimeSpan(0, 0, 0, 0, wparam), m));
}
break;
case MIM_MOREDATA:
break;
default:
break;
}
}
internal static MidiSequence ReadFrom(Stream stream)
{
MidiSequence result = new MidiSequence();
var rs = (byte)0;
var delta = _ReadVarlen(stream);
if (BitConverter.IsLittleEndian)
{
delta = _Swap(delta);
}
var i = stream.ReadByte();
while (-1 != i)
{
var hasStatus = false;
var b = (byte)i;
if (0x7F < b)
{
hasStatus = true;
rs = b;
i = stream.ReadByte();
if (-1 != i)
{
b = (byte)i;
}
else
{
b = 0;
}
}
var st = hasStatus ? rs : (byte)0;
var m = (MidiMessage)null;
switch (rs & 0xF0)
{
case 0x80:
if (i == -1)
{
throw new EndOfStreamException();
}
m = new MidiMessageNoteOff(b, (byte)stream.ReadByte(), unchecked ((byte)(st & 0x0F)));
break;
case 0x90:
if (i == -1)
{
throw new EndOfStreamException();
}
m = new MidiMessageNoteOn(b, (byte)stream.ReadByte(), unchecked ((byte)(st & 0x0F)));
break;
case 0xA0:
if (i == -1)
{
throw new EndOfStreamException();
}
m = new MidiMessageKeyPressure(b, (byte)stream.ReadByte(), unchecked ((byte)(st & 0x0F)));
break;
case 0xB0:
if (i == -1)
{
throw new EndOfStreamException();
}
m = new MidiMessageCC(b, (byte)stream.ReadByte(), unchecked ((byte)(st & 0x0F)));
break;
case 0xC0:
if (i == -1)
{
throw new EndOfStreamException();
}
m = new MidiMessagePatchChange(b, unchecked ((byte)(st & 0x0F)));
break;
case 0xD0:
if (i == -1)
{
throw new EndOfStreamException();
}
m = new MidiMessageChannelPressure(b, unchecked ((byte)(st & 0x0F)));
break;
case 0xE0:
if (i == -1)
{
throw new EndOfStreamException();
}
m = new MidiMessageChannelPitch(b, (byte)stream.ReadByte(), unchecked ((byte)(st & 0x0F)));
break;
case 0xF0:
switch (rs & 0xF)
{
case 0xF:
if (i == -1)
{
throw new EndOfStreamException();
}
var l = _ReadVarlen(stream);
//if (BitConverter.IsLittleEndian)
// l = _Swap(l);
var ba = new byte[l];
if (l != stream.Read(ba, 0, ba.Length))
{
throw new EndOfStreamException();
}
m = new MidiMessageMeta(st, b, ba);
break;
case 0x0:
case 0x7:
if (i == -1)
{
throw new EndOfStreamException();
}
l = _ReadVarlen(b, stream);
//if (BitConverter.IsLittleEndian)
// l = _Swap(l);
ba = new byte[l];
if (l != stream.Read(ba, 0, ba.Length))
{
throw new EndOfStreamException();
}
m = new MidiMessageSysex(st, ba);
break;
case 0x2:
if (i == -1)
{
throw new EndOfStreamException();
}
m = new MidiMessageWord(st, b, (byte)stream.ReadByte());
break;
case 0x3:
if (i == -1)
{
throw new EndOfStreamException();
}
m = new MidiMessageByte(st, b);
break;
case 0x6:
case 0x8:
case 0xA:
case 0xB:
case 0xC:
// status *was* specified if we got here
m = new MidiMessage(st);
break;
default:
throw new NotSupportedException("The MIDI message is not recognized.");
}
break;
}
result.Events.Add(new MidiEvent(delta, m));
i = _ReadVarlen(stream);
if (-1 == i)
{
break;
}
delta = i;
i = stream.ReadByte();
}
return(result);
}
