JamAudio

var JamSynth;
var JamKit;
var JamKitBox;
var JamScorePlayer;

(function()
{
    function constructStandardKitList(folder)
    {
        var toReturn = [];
        toReturn.push("/static/js/JamAudio/samples/" + folder + "/hihat.wav");
        toReturn.push("/static/js/JamAudio/samples/" + folder + "/kick.wav");
        toReturn.push("/static/js/JamAudio/samples/" + folder + "/snare.wav");
        toReturn.push("/static/js/JamAudio/samples/" + folder + "/tom1.wav");
        toReturn.push("/static/js/JamAudio/samples/" + folder + "/tom2.wav");
        toReturn.push("/static/js/JamAudio/samples/" + folder + "/tom3.wav");
        return toReturn;
    }

    var kitLoops =  {
        "acoustic": constructStandardKitList("acoustic"),
        "techno": constructStandardKitList("Techno"),
        "R8": constructStandardKitList("R8"),
        "bongos": constructStandardKitList("Bongos")
    };

    console.log(kitLoops);

    var Synth = Class.$extend(
    {
        __init__: function(context, sampleRate, numChannels)
        {
            sampleRate || (sampleRate = 44100);
            numChannels || (numChannels = 2);
            this.sample_rate(sampleRate);
            this.num_channels(numChannels);
            this._dsp = new signalProcessor();
            context ? this._context = context : this._context = new webkitAudioContext();
            this._masterGainNode = this._context.createGainNode();
            this._masterGainNode.gain.value = 0.7;
            this._masterGainNode.connect(this._context.destination);
            this._compressor = this._context.createDynamicsCompressor();
            this._compressor.connect(this._masterGainNode);
            this._convolver = this._context.createConvolver();
            this._convolver.connect(this._masterGainNode);
        },

        playNote: function(noteName, numSecs, gain, convolutions)
        {
            return this.playHertz(this._getHertz(noteName), numSecs, gain, convolutions);
        },

        playHertz: function(hertz, numSecs, gain, convolutions)
        {
            numSecs || (numSecs = 1);
      gain || (gain = 1);
            (g = ((hertz < 200) ? 3 :
            (hertz < 600) ? 1.5 :
            (hertz < 800) ? 1 : 0.7));
      gain = g * gain;
      console.log(gain);

            var source = this._context.createBufferSource();
      multiple = 0;
      while(multiple < 42000) multiple += hertz;
      framelen = numSecs > 0 ? numSecs * multiple: multiple;
            sample = multiple;

      source.buffer = this._context.createBuffer(this.num_channels(), framelen, sample );
            var osc = new this._dsp.Oscillator(this._dsp.SINE, hertz, gain, framelen, sample );
            osc.generate();

            for(var i = 0; i < this.num_channels(); ++i)
            {
                source.buffer.getChannelData(i).set(osc.signal);
            }

            var filter = this._context.createBiquadFilter();
            filter.frequency.value = 22050;
            filter.Q.value = 5;
            source.connect(filter);

            var dryGainNode = this._context.createGainNode();
            dryGainNode.gain.value = gain;
            filter.connect(dryGainNode);
            dryGainNode.connect(this._compressor);

            var wetGainNode = this._context.createGainNode();
            wetGainNode.gain.value = gain;
            filter.connect(wetGainNode);
            wetGainNode.connect(this._convolver);

            if(numSecs < 0) source.looping = true;
            source.noteOn(0);
            var obj = {};
            obj._source = source;
            obj.stop = function() { this._source.noteOff(0); };
            return obj;
        },

        _getHertz: function(noteName)
        {
            var noteTable = { "G9": 0x7F, "Gb9": 0x7E, "F9": 0x7D, "E9": 0x7C, "Eb9": 0x7B,
            "D9": 0x7A, "Db9": 0x79, "C9": 0x78, "B8": 0x77, "Bb8": 0x76, "A8": 0x75, "Ab8": 0x74,
            "G8": 0x73, "Gb8": 0x72, "F8": 0x71, "E8": 0x70, "Eb8": 0x6F, "D8": 0x6E, "Db8": 0x6D,
            "C8": 0x6C, "B7": 0x6B, "Bb7": 0x6A, "A7": 0x69, "Ab7": 0x68, "G7": 0x67, "Gb7": 0x66,
            "F7": 0x65, "E7": 0x64, "Eb7": 0x63, "D7": 0x62, "Db7": 0x61, "C7": 0x60, "B6": 0x5F,
            "Bb6": 0x5E, "A6": 0x5D, "Ab6": 0x5C, "G6": 0x5B, "Gb6": 0x5A, "F6": 0x59, "E6": 0x58,
            "Eb6": 0x57, "D6": 0x56, "Db6": 0x55, "C6": 0x54, "B5": 0x53, "Bb5": 0x52, "A5": 0x51,
            "Ab5": 0x50, "G5": 0x4F, "Gb5": 0x4E, "F5": 0x4D, "E5": 0x4C, "Eb5": 0x4B, "D5": 0x4A,
            "Db5": 0x49, "C5": 0x48, "B4": 0x47, "Bb4": 0x46, "A4": 0x45, "Ab4": 0x44, "G4": 0x43,
            "Gb4": 0x42, "F4": 0x41, "E4": 0x40, "Eb4": 0x3F, "D4": 0x3E, "Db4": 0x3D, "C4": 0x3C,
            "B3": 0x3B, "Bb3": 0x3A, "A3": 0x39, "Ab3": 0x38, "G3": 0x37, "Gb3": 0x36, "F3": 0x35,
            "E3": 0x34, "Eb3": 0x33, "D3": 0x32, "Db3": 0x31, "C3": 0x30, "B2": 0x2F, "Bb2": 0x2E,
            "A2": 0x2D, "Ab2": 0x2C, "G2": 0x2B, "Gb2": 0x2A, "F2": 0x29, "E2": 0x28, "Eb2": 0x27,
            "D2": 0x26, "Db2": 0x25, "C2": 0x24, "B1": 0x23, "Bb1": 0x22, "A1": 0x21, "Ab1": 0x20,
            "G1": 0x1F, "Gb1": 0x1E, "F1": 0x1D, "E1": 0x1C, "Eb1": 0x1B, "D1": 0x1A, "Db1": 0x19,
            "C1": 0x18, "B0": 0x17, "Bb0": 0x16, "A0": 0x15, "Ab0": 0x14, "G0": 0x13, "Gb0": 0x12,
            "F0": 0x11, "E0": 0x10, "Eb0": 0x0F, "D0": 0x0E, "Db0": 0x0D, "C0": 0x0C };
            var a4 = noteTable["A4"];
            var note = noteTable[noteName];
            if(!note) throw new Error("You entered a note that does not exist! " + noteName);
            return 440 * Math.pow(2, (note - a4)/12);
        },

        __instancevars__: ["sample_rate", "num_channels"]
    });

    var Kit = Class.$extend(
    {
        __init__: function(kitPaths, loadCallback, context, sampleRate, numChannels)
        {
            sampleRate || (sampleRate = 44100);
            numChannels || (numChannels = 2);
            this.sample_rate(sampleRate);
            this.num_channels(numChannels);
            if(!loadCallback) throw new Error("You have to hand me a callback function!");
            this._loadCallback = loadCallback;
            if(!kitPaths || !kitPaths.length || kitPaths.length < 1) throw new Error("You didn't enter anything for my kit!");
            this.kit_paths(kitPaths);
            context ? this._context = context : this._context = new webkitAudioContext();
            this._masterGainNode = this._context.createGainNode();
            this._masterGainNode.gain.value = 0.7;
            this._masterGainNode.connect(this._context.destination);
            this._compressor = this._context.createDynamicsCompressor();
            this._compressor.connect(this._masterGainNode);
            this._convolver = this._context.createConvolver();
            this._convolver.connect(this._masterGainNode);

            var buffers = [];
            for(var i = 0 ; i < this.kit_paths().length; ++i) buffers.push(0);
            this.buffers(buffers);

            this._loadCount = 0;
            for(var j = 0; j < this.kit_paths().length; ++j)
            {
                this.loadSample(j);
            }

            this._hasEffect = false;
        },

        loadSample: function(sampleId)
        {
            var request = new XMLHttpRequest();
            request.open("GET", this.kit_paths()[sampleId], true);
            request.responseType = "arraybuffer";
            var self = this;
            request.onload = function()
            {
                var buffer = self._context.createBuffer(request.response, false);
                self.buffers()[sampleId] = buffer;
                self._loadCount++;
                if(self._loadCount == self.kit_paths().length) self._loadCallback();
            };

            request.send();
        },

        playIndex: function(index, sendGain, mainGain, cutoff, resonance)
        {
            var source = this._context.createBufferSource();
            source.buffer = this.buffers()[index];

            var filter = this._context.createBiquadFilter();
            filter.frequency.value = cutoff;
            filter.Q.value = resonance;

            source.connect(filter);

            var dryGainNode = this._context.createGainNode();
            dryGainNode.gain.value = mainGain;
            filter.connect(dryGainNode);
            dryGainNode.connect(this._compressor);

            if(this._hasEffect) {
                var wetGainNode = this._context.createGainNode();
                wetGainNode.gain.value = sendGain;
                filter.connect(wetGainNode);
                wetGainNode.connect(this._convolver);
            }

            source.noteOn(0);
        },

        playNote: function(noteName, sendGain, mainGain, cutoff, resonance)
        {
            var index = this._getNoteIndex(noteName);
            console.log(index);
            this.playIndex(index, sendGain, mainGain, cutoff, resonance);
        },

        _getNoteIndex: function(noteName)
        {
            var noteTable = { "G9": 0x7F, "Gb9": 0x7E, "F9": 0x7D, "E9": 0x7C, "Eb9": 0x7B,
            "D9": 0x7A, "Db9": 0x79, "C9": 0x78, "B8": 0x77, "Bb8": 0x76, "A8": 0x75, "Ab8": 0x74,
            "G8": 0x73, "Gb8": 0x72, "F8": 0x71, "E8": 0x70, "Eb8": 0x6F, "D8": 0x6E, "Db8": 0x6D,
            "C8": 0x6C, "B7": 0x6B, "Bb7": 0x6A, "A7": 0x69, "Ab7": 0x68, "G7": 0x67, "Gb7": 0x66,
            "F7": 0x65, "E7": 0x64, "Eb7": 0x63, "D7": 0x62, "Db7": 0x61, "C7": 0x60, "B6": 0x5F,
            "Bb6": 0x5E, "A6": 0x5D, "Ab6": 0x5C, "G6": 0x5B, "Gb6": 0x5A, "F6": 0x59, "E6": 0x58,
            "Eb6": 0x57, "D6": 0x56, "Db6": 0x55, "C6": 0x54, "B5": 0x53, "Bb5": 0x52, "A5": 0x51,
            "Ab5": 0x50, "G5": 0x4F, "Gb5": 0x4E, "F5": 0x4D, "E5": 0x4C, "Eb5": 0x4B, "D5": 0x4A,
            "Db5": 0x49, "C5": 0x48, "B4": 0x47, "Bb4": 0x46, "A4": 0x45, "Ab4": 0x44, "G4": 0x43,
            "Gb4": 0x42, "F4": 0x41, "E4": 0x40, "Eb4": 0x3F, "D4": 0x3E, "Db4": 0x3D, "C4": 0x3C,
            "B3": 0x3B, "Bb3": 0x3A, "A3": 0x39, "Ab3": 0x38, "G3": 0x37, "Gb3": 0x36, "F3": 0x35,
            "E3": 0x34, "Eb3": 0x33, "D3": 0x32, "Db3": 0x31, "C3": 0x30, "B2": 0x2F, "Bb2": 0x2E,
            "A2": 0x2D, "Ab2": 0x2C, "G2": 0x2B, "Gb2": 0x2A, "F2": 0x29, "E2": 0x28, "Eb2": 0x27,
            "D2": 0x26, "Db2": 0x25, "C2": 0x24, "B1": 0x23, "Bb1": 0x22, "A1": 0x21, "Ab1": 0x20,
            "G1": 0x1F, "Gb1": 0x1E, "F1": 0x1D, "E1": 0x1C, "Eb1": 0x1B, "D1": 0x1A, "Db1": 0x19,
            "C1": 0x18, "B0": 0x17, "Bb0": 0x16, "A0": 0x15, "Ab0": 0x14, "G0": 0x13, "Gb0": 0x12,
            "F0": 0x11, "E0": 0x10, "Eb0": 0x0F, "D0": 0x0E, "Db0": 0x0D, "C0": 0x0C };
            var c0 = noteTable["C0"];
            var note = noteTable[noteName];
            console.log(c0);
            console.log(note);
            return (note - c0) % this.kit_paths().length;
        },

        __instancevars__: ["sample_rate", "num_channels", "kit_paths", "buffers"]
    });

    /*
     *  Library for a bunch of kits to share an audiocontext.
     *  Also convenient for playing notes.
     */
    var KitBox = Class.$extend(
    {
        __init__: function()
        {
            this._kits = {};
            this._context = new webkitAudioContext();
            this._kits["synth"] = new Synth(this._context);
        },

        loadKit: function(kitName, kitList, callbackFn)
        {
            console.log(kitList);
            this._kits[kitName] = new Kit(kitList, callbackFn, this._context);
        },

        loadKitByName: function(kitName, callbackFn)
        {
            console.log(kitLoops);
            this.loadKit(kitName, kitLoops[kitName], callbackFn);
        },

        loadKitsByNames: function(kitNames, callbackFn)
        {
            var curCount = 0;
            var total = kitNames.length;
            var fn = function()
            {
                curCount++;
                if(curCount === total) callbackFn();
            };
            for(var i = 0; i < kitNames.length; ++i)
            {
                this.loadKitByName(kitNames[i], fn);
            }
        },

        playNote: function(kitName, noteName, numSecs)
        {
            if(numSecs && (this._kits[kitName] instanceof Synth)) this._kits[kitName].playNote(noteName, numSecs);
            this._kits[kitName].playNote(noteName);
        }
    });

    /*
     *  Library to play a score
     */
    var ScorePlayer = Class.$extend(
    {
        __init__: function(score, callbackFn)
        {
            this.score(score);
            this.kitBox(new KitBox());
            var self = this;
            this.kitBox().loadKitsByNames(["acoustic", "techno", "R8", "bongos"], function() { self._ready = true; callbackFn(); });
            this._ready = false;
            this._playing = false;
        },

        startPlaying: function(startPosition)
        {
            if(!this._ready) return;
            var startIndex;
            for(var i = 0; i < this.score().notes().length; ++i)
            {
                console.log(this.score().notes()[i].start());
                if(startPosition <= this.score().notes()[i].start()) {
                    startIndex = i;
                    break;
                }
            }
            if(startPosition >= this.score().notes().length) return;
            this._playing = true;
            var startTime = this.score().getTimeForBeat(startPosition);
            var firstNoteTime = this.score().getTimeForBeat(this.score().notes()[startIndex].start());
            var self = this;
            setTimeout( function() { self.asyncPlay(startIndex, self); }, 1000 * (firstNoteTime - startTime) );
        },

        asyncPlay: function(index, self)
        {
            if(!self._playing) return;
            if(index >= self.score().notes().length) {
                self._playing = false;
                return;
            }

            var note = self.score().notes()[index];
            self.kitBox().playNote(note.instrument(), note.value(), self.score().getLengthForNote(note.start(), note.length()));

            if(index + 1 >= self.score().notes().length) {
                self._playing = false;
                return;
            }
            var curNoteTime = this.score().getTimeForBeat(self.score().notes()[index].start());
            var nextNoteTime = this.score().getTimeForBeat(self.score().notes()[index + 1].start());
            setTimeout( function() { self.asyncPlay(index + 1, self); }, 1000 * (nextNoteTime - curNoteTime) );
        },

        stopPlaying: function()
        {
            this._playing = false;
        },

        __instancevars__: ["score", "kitBox"]
    });

    JamSynth = Synth;
    JamKit = Kit;
    JamKitBox = KitBox;
    JamScorePlayer = ScorePlayer;

})();