/*
Nathan O'Neel
Chord Player v1.0
6/8/19
*/

var activeNotes = [];
var sustainedNotes = [];
var posActiveNotes = [];
var lowestNotePitch = -1;
var chordBasePitch = -1;
var HIGH_RANGE;
var LOW_RANGE;
var CHORD_VELOCITY = 110;
var SEND_ALL_NOTES_ON = true;

var isSustained = false;
var lastNoteVelocity = -1;

// ex:           C2  C3  G3
var chordNotes = [0, 12, 19];
var chordNoteTranslated = [];
var tempPitch = -1;

function chordOn() {
  chordOff();
	chordBasePitch = lowestNotePitch;
		for(var i = 0; i < chordNotes.length; i++) {
			var noteOn = new NoteOn();

		  	chordNoteTranslated[i] = chordBasePitch + chordNotes[i];
      			if(chordNoteTranslated[i] > HIGH_RANGE) {
        			tempPitch = chordNoteTranslated[i] - 12;
				while(tempPitch > HIGH_RANGE && !chordNoteTranslated.includes(tempPitch)) {
				  tempPitch -= 12;
				}
        			chordNoteTranslated[i] = tempPitch;
      			}
		  	if(chordNoteTranslated[i] < LOW_RANGE) {
			  	tempPitch = chordNoteTranslated[i] + 12;
				while(tempPitch < LOW_RANGE && !chordNoteTranslated.includes(tempPitch)) {
					tempPitch += 12;
				}
				chordNoteTranslated[i] = tempPitch;
			}

			noteOn.pitch = chordNoteTranslated[i];
			if(CHORD_VELOCITY == 0) {
				noteOn.velocity = lastNoteVelocity
			} else {
				noteOn.velocity = CHORD_VELOCITY;
			}
			noteOn.send();
		}
}
function chordOff() {
	for(var i = 0; i < chordNotes.length; i++) {
	  var noteOff = new NoteOff();
		noteOff.pitch = chordNoteTranslated[i]
		//noteOff.velocity = CHORD_VELOCITY;
		noteOff.send();
	}
}


function getLowestNoteFromActive() {
	lowestNotePitch = 127; // The max possible
	var susLength = sustainedNotes.length;
	var actLength = activeNotes.length;

	if(actLength == 0 && susLength == 0) {
		lowestNotePitch = -1;
		chordOff();
	  	return;
	}
	var amount = Math.max(actLength, susLength);
	for(var i = 0; i < amount; i++) {
		if(i < actLength) {
			if(activeNotes[i] < lowestNotePitch) {
			  lowestNotePitch = activeNotes[i];
			}
		}
		if(i < susLength) {
			if(sustainedNotes[i] < lowestNotePitch) {
				lowestNotePitch = sustainedNotes[i];
			}
		}
	}

	// if I know that there is a note on, and if its not the same note as before
	if(lowestNotePitch != -1 && lowestNotePitch != chordBasePitch) {
		chordOn();
	}
}

function HandleMIDI (event) {
		if (event instanceof NoteOn) {
		lastNoteVelocity = event.velocity;
 		if(isSustained) {
 			if(sustainedNotes.indexOf(event.pitch) == -1) {
 				sustainedNotes.push(event.pitch);
 			}
 		} else {
 			if(activeNotes.indexOf(event.pitch) == -1) {
 				activeNotes.push(event.pitch);
 			}
 		}
 		if(posActiveNotes.indexOf(event.pitch) == -1 ) posActiveNotes.push(event.pitch);
 		if(event.pitch < lowestNotePitch || lowestNotePitch == -1) {
 			lowestNotePitch = event.pitch;
 			chordOn();
 		}
 		if(SEND_ALL_NOTES_ON) {
 			event.send();
 		}

		} else if (event instanceof NoteOff) {
		  var indexOfNote = activeNotes.indexOf(event.pitch);
		  if(indexOfNote != -1) {
			  activeNotes.splice(indexOfNote, 1);
		  }
			var indexOfPossible = posActiveNotes.indexOf(event.pitch);
			if(indexOfPossible != -1) {
					posActiveNotes.splice(indexOfPossible, 1);
			}
		  if(event.pitch == lowestNotePitch) {
			  getLowestNoteFromActive();
		  }
			event.send();
		} else if(event.number == 64) {
		  if(event.value == 127) {
			  isSustained = true;
			  sustainedNotes = sustainedNotes.concat(activeNotes);
			  activeNotes = posActiveNotes;
		  } else if(event.value == 0) {
			  isSustained = false;
			  sustainedNotes = [];
			  activeNotes = posActiveNotes;
			  getLowestNoteFromActive();
		  }
		event.send();
	} else {
			event.send();
	}
}

function ParameterChanged (param, value) {
		switch (param) {
				case 0:
					HIGH_RANGE = value;
					if (value < LOW_RANGE) {
							SetParameter(1, value);
					}
					break;
				case 1:
					LOW_RANGE = value;
					if (value > HIGH_RANGE) {
							SetParameter(0, value);
					}
					break;
				case 2:
					CHORD_VELOCITY = value;
					break;
				case 3:
					SEND_ALL_NOTES_ON = (value === 0);
				break;
					default:
						//nothing
		}

}

var PluginParameters = [{
		name:"High Range",
		type:"linear",
		minValue:0,
		maxValue:127,
		numberOfSteps:127,
		defaultValue:72
}, {
		name:"Low Range",
		type:"linear",
		minValue:0,
		maxValue:127,
		numberOfSteps:127,
		defaultValue:48
}, {
	type:"text",
	name:"When zero, velocity = last note's velocity."
}, {
		name:"Chord Velocity",
		type:"linear",
		minValue:0,
		maxValue:127,
		numberOfSteps:127,
		defaultValue:0
}, {
	name:"Send All Notes On",
		type:"menu",
		valueStrings:["On", "Off"],
		defaultValue:1,
		numberOfSteps:2
}];