// Jazz 081417 -- An experiment in JavaScript jazz improvisation.
// I cleaned up a few things from an eailer version.
// John Clavin -- August 14, 2017

var noteArray = [52,53,54,55,56,57,58,59,60,61,62,63,64,
                65,66,67,68,69,70,71,72,73,74,75,76,77];
                    
var dorianTemplate = [2,0,1,2,0,1,0,2,0,1,2,0,
                      2,0,1,2,0,1,0,2,0,1,2,0,
                      2,0,1,2,0,1,0,2,0,1,2,0,2,0];
                      
var tempKeyArray = [2,0,1,2,0,1,0,2,0,1,2,0,
                  2,0,1,2,0,1,0,2,0,1,2,0,2,0];
                  
var parserDirFlag;
var parserIndex;
var voiceArray = [];
var music;
var goMusic = true;
var xPos = 0;

function setup() {
  createCanvas(960, 400);
  frameRate(60);
  rectMode(CENTER);
  noStroke();
  background(238);
  masterVolume(0.30);
  parserDirFlag = true;
  parserIndex = 4;
  for (var v = 0; v < 4; v++) {
    voice = new jcOsc();  
    voiceArray.push(voice);
  }
  music = new MusicManagement();
  music.composeSpaces();
}

function draw() {
  if (goMusic) {
    music.manage();
  }
}

function MusicManagement() {
  this.timeSpaces = [];
  this.tsCounter = 0;
  
  this.composeSpaces = function() {
    for (var i = 0; i < 248; i++) {
      var s = new TimeSpace();
      this.timeSpaces.push(s);
    }
    for (var j = 0; j < this.timeSpaces.length; j++) {
      this.timeSpaces[j].compose();
    }
  } 
  
  this.manage = function() {
    this.timeSpaces[this.tsCounter].musicGraphics();
    if ((this.tsCounter + 1) < this.timeSpaces.length) {
      if (this.timeSpaces[this.tsCounter].timeFinishedFlag === false) {
        this.timeSpaces[this.tsCounter].play();  
      } else {
        this.timeSpaces[this.tsCounter].timeFinishedFlag = false;
        this.tsCounter++;
        this.timeSpaces[this.tsCounter].play();
      }
    } else {
      goMusic = false;
    }
  }
}

function TimeSpace() {
  this.restFlag = false;
  this.noteStartedFlag = false;
  this.timeFinishedFlag = false;
  this.noteFoundFlag = false;
  this.hiNotesFlag = false;
  this.musicKey = 0;
  this.notes2Play = [];
  this.musicTime = 0;
  this.numberOfNotes = 0;
  
  this.compose = function() {
    if (random(100) < 7) {
      this.musicKey = int(random(12));
      for ( var i = 0; i < noteArray.length; i++) {
        tempKeyArray[i] = dorianTemplate[i + this.musicKey]; 
      }
    }
    if (random(100) < 80) {
      this.numberOfNotes = 1; 
    } else {
      this.numberOfNotes = int(random(2, 5));
    }
    if (this.numberOfNotes == 1) {
      this.musicTime = 9;
      noteFoundFlag = false;
      while(noteFoundFlag === false) {
        if(tempKeyArray[parserIndex] > 0) {
          var note = noteArray[parserIndex];
          this.notes2Play[0] = note;
          noteFoundFlag = true;
        }
        this.parserMove();
      }
      if (random(100) < 40) {
        if (this.hiNotesFlag === true) {
          parserIndex = int(random(4, 11));  
        } else { 
          parserIndex = int(random(13, 20));
        }
        parserDirFlag = !parserDirFlag;
        noteFoundFlag = false;
        while(noteFoundFlag === false) {
          if(tempKeyArray[parserIndex] == 2) {
            note = noteArray[parserIndex];
            this.notes2Play[0] = note;
            noteFoundFlag = true;
          }
          this.parserMove();
        }
      }
    } else {
      this.musicTime = 36;
      for (var j = 0; j < 4; j++) {
        noteFoundFlag = false;  
        while(noteFoundFlag === false) {
          if(tempKeyArray[parserIndex] == 2) {
            note = noteArray[parserIndex];
            this.notes2Play[j] = note;
            noteFoundFlag = true;
          }
          this.parserMove();
        }
      }
    }
  }
	
  this.parserMove = function() {
    if (parserIndex >= 24) {
      parserDirFlag = false;
    }
    if (parserIndex <= 1) {
      parserDirFlag = true;
    }
    if (parserDirFlag === true) {
      parserIndex++;
    } else {
      parserIndex--;
    }
    if (parserIndex > 12) {
      this.hiNotesFlag = true;
    } else {
      this.hiNotesFlag = false;
    }
  }
  
  this.play = function() {
    if (this.restFlag === true) {
      if (this.musicTime > 0) {
        this.musicTime--;
      } else {
        this.timeFinishedFlag = true;  
      }
    } else {
      if (this.noteStartedFlag === false) {
        for (var n = 0; n < this.numberOfNotes; n++) {
          voiceArray[n].jamOn(this.notes2Play[n]);
        }
        this.noteStartedFlag = true;
      }
      if (this.musicTime > 0) {
        this.musicTime--;
      } else {
        this.timeFinishedFlag = true;
        this.noteStartedFlag = false;
      }
    }
  }
  
  this.musicGraphics = function() {
    xPos = xPos + 0.25;
    for (var n = 0; n < this.numberOfNotes; n++) {
      var yPos = map(this.notes2Play[n], 77, 52, 0, height);
      noStroke();
      if (this.numberOfNotes > 1) {
        fill(0);
      } else {
        fill(200, 0, 0);
      }
      rect(xPos, yPos, 6, 12);
    }
  }
}

function jcOsc() {
  this.osc1 = new p5.SawOsc();
  this.osc2 = new p5.SawOsc();
  this.osc1Env = new p5.Env();
  this.osc2Env = new p5.Env();
  this.osc1Env.setADSR(0.004, 0.25, 0.2, 0.8);
  this.osc2Env.setADSR(0.004, 0.15, 0.2, 0.8);
  this.osc1Env.setRange(0.60, 0);
  this.osc2Env.setRange(0.60, 0);
  this.osc1.amp(this.osc1Env);
  this.osc2.amp(this.osc2Env);
  this.osc1.start();
  this.osc2.start();

  this.jamOn = function(xnote) {
    this.note = xnote;
    this.osc1Freq = midiToFreq(this.note);
    this.osc2Freq = midiToFreq(this.note);
    this.osc1.freq(this.osc1Freq);
    this.osc2.freq(this.osc2Freq * 1.004);
    this.osc1Env.play();
    this.osc2Env.play();	
  }
}