#define BAUDRATE      115200
#define BAUDRATE_MIDI  31250

void midiout_write(uint8_t value) {
	return;
}

// 音を鳴らす
void noteOn(uint8_t channel, uint8_t note, uint8_t velocity)
{
	Serial1.write(channel);
	Serial1.write(note);
	Serial1.write(velocity);
//Serial1.printf("%02x %02x %02x\n",channel,note,velocity);
}

// 音を止める
void noteOff(uint8_t channel, uint8_t note, uint8_t velocity)
{
	Serial1.write(channel);
	Serial1.write(note);
	Serial1.write(velocity);
//Serial1.printf("%02x %02x %02x\n",channel,note,velocity);
}

// 演奏に使用する音色(楽器)を指定する
void setInstrument(uint8_t control, uint8_t instrument)
{
	Serial1.write(control);
	Serial1.write(instrument);
//Serial1.printf("%02x %02x\n",control,instrument);
}

void receiveEvent()
{
	static unsigned char bufMidi[4];
	static unsigned char uch;
	static int pos = 0;
	static int cmdlen;

	if (Serial.available()) {
		bufMidi[pos] = Serial.read();
		if (pos==0) {
			uch = bufMidi[pos] & 0xF0;
			switch(uch) {
				case 0x90: // Note-on
				case 0x80: // Note-off
				case 0xB0: // Continuous controller
				case 0xE0: // Pitch bend
					cmdlen = 3;
					break;
				case 0xA0: // After-touch
				case 0xC0: // Program change
					cmdlen = 2;
					break;
				case 0xD0: // Channel Pressure
					cmdlen = 0;
					break;
				case 0xF0: // System Realtime message (non-musical commands)
					midiout_write(bufMidi[0]);
					cmdlen = 0;
					break;
				case 0xFF:
					cmdlen = 0;
					break;
				default:
					cmdlen = 0;
					break;
			}
			if (cmdlen>0) pos++;
		} else {
			pos++;
			if (pos==cmdlen) {
				switch(uch) {
					case 0x90:
						noteOn(bufMidi[0], bufMidi[1], bufMidi[2]);
						break;
					case 0x80:
						noteOff(bufMidi[0], bufMidi[1], bufMidi[2]);
						break;
					case 0xB0: // Continuous controller
					case 0xE0: // Pitch bend
						midiout_write(bufMidi[0]);
						midiout_write(bufMidi[1]);
						midiout_write(bufMidi[2]);
						break;
					case 0xA0: // After-touch
					case 0xC0: // Program change
						setInstrument(bufMidi[0], bufMidi[1]);
						break;
				}
				pos = 0;
			} else {
				if (pos==4) pos=0;
			}
		}
	}
}

void setup()
{
	Serial.begin(BAUDRATE);
	Serial1.begin(BAUDRATE_MIDI);
}

void loop()
{
	receiveEvent();
}