var environment = (function(){

  var environment = {}
  
  var image_index = -1
  var snap, dot_grid, polysynth
  var strided_wires = [], wires = []
  var scale = [], root, tet, interval, duration
  var dot_color = "#333"
  var drawing = true

  var palette = [
    "#ff0000",
    "#00ffff",
    "#0000ff",
    "#ff8800",
    "#ffff00",
  ]
  
  environment.init = function(){
    if (is_mobile) {
      environment.request_audio_context()
    }
    else {
      environment.ready()
    }
  }
  environment.ready = function(){
    environment.build()
    environment.bind()
  }
  environment.request_audio_context = function(){
		var element = $("<div>", {"id" : "MobileStart"}).appendTo("body")
		var button = $("<div>").attr("id", "Button").html("Enter<br>(please unmute your phone)").appendTo(element)
		StartAudioContext.setContext(Tone.context)
		StartAudioContext.on(button)
		StartAudioContext.onStarted(function(){
			element.remove()
      environment.ready()
		})
  }
  environment.build = function(){
    environment.scale()
    environment.duration()
    environment.set_intervals()
    snap = new Snap (window.innerWidth, window.innerHeight - $("#controls").height())

    dot_grid = new DotGrid ()
    dot_grid.load()
    
    polysynth = new Tone.PolySynth(8, Tone.synth)
    polysynth.set({
      oscillator: { type: $("#waveform").val() },
      envelope:{
        attack: 0.01,
        decay: 2.5,
        sustain: 0.0,
        release: 0.1,
      }
    })
//     polysynth = new Tone.PolySynth(8, Tone.FMSynth)
//     polysynth.set({
//       harmonicity:2,
//       modulationIndex:3,
//       detune:0,
//       oscillator:{
//         type:"sine",
//       },
//       envelope:{
//         attack:0.01,
//         decay:0.01,
//         sustain:1,
//         release:0.2,
//       },
//       moduation:{
//         type:"sawtooth",
//       },
//       modulationEnvelope:{
//         attack:0.1,
//         decay:0,
//         sustain:1,
//         release:0.2,
//       }
//     })
//     polysynth.set({
//       oscillator: { type: $("#waveform").val() },
//       envelope:{
//         attack: 0.01,
//         decay: 2.5,
//         sustain: 0.0,
//         release: 0.1,
//       }
//     })

    var comp = new Tone.Compressor(-30, 3).toMaster()
//     var reverb = new Tone.Freeverb ()
//     reverb.wet.value = 0.01
//     polysynth.connect(reverb)
//     reverb.connect(comp)
    polysynth.connect(comp)
    // environment.stride()
    // environment.randomize()
  }
  environment.bind = function(){
    $(window).focus(environment.focus)
    $(window).blur(environment.blur)
    window.addEventListener("keydown", environment.keydown, true)
    $("#waveform").on("input", environment.setWaveform)
    $("#x").on("keydown", environment.stride)
    $("#y").on("keydown", environment.stride)
    $("#rand").on("input", environment.randomize)
    $("#tet").on("input", environment.scale)
    $("#root").on("input", environment.scale)
    $("#interval").on("input", environment.scale)
    $("#intervals").on("input", environment.set_intervals)
    $("#duration").on("input", environment.duration)
    $("#use_scale").on("change", environment.use_scale)
    if (is_mobile) {
      snap.node.addEventListener("touchstart", getFirstTouch( dot_grid.mousedown.bind(dot_grid) ))
      document.addEventListener("touchmove", getFirstTouch( environment.mousemove))
      document.addEventListener("touchend", dot_grid.mouseup.bind(dot_grid) )
      $("#draw").on("touchstart", environment.check_drawing)
      $("#reset").on("touchstart", environment.reset)
    }
    else {
      $(snap.node).on("mousedown", dot_grid.mousedown.bind(dot_grid))
      $(window).mousemove(environment.mousemove)
      $(window).on("mouseup", dot_grid.mouseup.bind(dot_grid))
    }
  }
  environment.blur = function(){
    last_p = null
  }
  environment.focus = function(){
  }
  environment.use_scale = function(){
    use_scale = $("#use_scale").get(0).checked
  }
  environment.set_intervals = function(){
    scale = $("#intervals").val().split(" ").map(parseInterval).filter(function(v){
      return !! v
    }).map(function(v){
      return v * root
    })
  }
  environment.check_drawing = function(){
    drawing = ! drawing
    $("#draw").html( drawing ? "drawing" : "playing" )
  }
  environment.reset = function(){
    environment.reset_wires()
  }
  environment.duration = function(){
    duration = parseInt( $("#duration").val() ) || 1000
    duration /= 1000
  }
  environment.keydown = function(e){
    if (e.altKey || e.ctrlKey || e.metaKey) {
      e.stopPropagation()
      return
    }
    if (e.keyCode == 69) { // charcode: e
      e.preventDefault()
    }
    if (document.activeElement instanceof HTMLInputElement &&
        (e.keyCode in key_numbers)) {
      e.stopPropagation()
      return
    }
    if (! (e.keyCode in keys)) return
    var i = keys[e.keyCode]
    if (e.shiftKey) i += letters.length
    var wire = wires[ i % wires.length ]
    wire && wire.play()
  }
  environment.setWaveform = function(){
    var w = $("#waveform").val()
    polysynth.set({ oscillator: { type: w } })
  }
  environment.last_p = { x: 0, y: 0 }
  environment.positionFromEvent = function(e){
    var offset = $(snap.node).offset()
    var p = {
      x: e.pageX - offset.left,
      y: e.pageY - offset.top,
    }
    return p
  }
  environment.mousemove = function(e){
    var p = environment.positionFromEvent(e)
    if (dot_grid.active) {
      dot_grid.active.update({
        point: p,
        muted: false,
        moving: true,
        duration: 0.2,
      })
    }
    else {
      wires.forEach(function(wire){
        wire.intersect(p, environment.last_p)
      })
    }
    environment.last_p = p
  }
  environment.stride = function(e){
    var dx = parseFloat( $("#x").val() )
    var dy = parseFloat( $("#y").val() )
    environment.reset_strided_wires()
    if (! dx && ! dy) return
    if (dx < 1.1 && ! dy) return
    var x0 = 0, x1 = dx, y0 = 0, y1 = dy
    var wire
    do {
      wire = new Wire ({
        head: { x: x0, y: y0 },
        tail: { x: x1, y: y1 },
        color: { h: Math.round(y0 / dot_grid.dots[0].length * 180 + 180), s: 100, l: 50 },
        integer: true,
      })
      strided_wires.push(wire)
      if (dx || ! dy) x0 += 1
      y0 += 1
      x1 += dy
      y1 += dx
    }
    while ( y0 < dot_grid.dots.length)
  }
  environment.reset_strided_wires = function(){
    strided_wires.forEach(function(wire){
      wire.remove()
    })
    strided_wires = []
  }
  environment.reset_wires = function(){
    wires.forEach(function(wire){
      wire.remove(true)
    })
    wires.length = 0
  }
  environment.randomize = function(){
    var n = parseInt( $("#rand").val() )
    environment.reset_strided_wires()
    var x0, y0, x1, y1
    while (n--) {
      x0 = randint( dot_grid.dots.length )
      x1 = randint( dot_grid.dots.length )
      y0 = randint( dot_grid.dots[0].length )
      y1 = randint( dot_grid.dots[0].length )
      wire = new Wire ({
        head: { x: x0, y: y0 },
        tail: { x: x1, y: y1 },
        color: { h: Math.round(y0 / dot_grid.dots[0].length * 180 + 180), s: 100, l: 50 },
        integer: true,
      })
      strided_wires.push(wire)
    }
  }
  environment.scale = function(e){
    if (e && e.keyCode && ! key_numbers(e.keyCode)) {
      e.preventDefault()
      return
    }
    var ratio, n
    tet = parseFloat( $("#tet").val() )
    root = parseFloat( $("#root").val() )
    interval = parseInterval( $("#interval").val() )
    ratio = Math.pow( interval, 1/tet )
    n = root
    scale = [n]
    for (var i = 0; i < tet; i++) {
      n *= ratio
      scale.push(n)
    }
    wires.forEach(function(wire){
      wire.updateColor(true)
    })
  }
  // quantize a frequency to the scale
  environment.quantize_frequency = function(f, get_index){
    if (f == 0) return 0
    var scale_f = f
    var pow = 0
    while (scale_f < root) {
      scale_f *= interval
      pow -= 1
    }
    while (scale_f > root*interval) {
      scale_f /= interval
      pow += 1
    }
    for (var i = 0; i < scale.length; i++) {
      if (scale_f > scale[i]) continue
      scale_f = scale[i]
      break
    }
    if (get_index) { return i }
    scale_f *= Math.pow(2, pow)
    // console.log(scale_f)
    return scale_f
  }
  environment.quantize_index = function(index){
    return mod(index, scale.length-1)|0
  }
  environment.index_to_frequency = function(index){
    var f = scale[ mod(index, scale.length-1)|0 ]
    var pow = Math.floor(norm(index, 0, scale.length-1)) - 2
    f *= Math.pow(interval, pow)
    // console.log(index, scale.length, pow, f)
    return f
  }


  function DotGrid (opt){
    this.opt = defaults(opt, {
      dot_radius: 4,
      dot_spacing: 20,
      mouse_radius: 200,
      wave_width: 200,
      fill: "#ffffff",
      speed: 4,
      ease: 10,
    })
    this.active = null
    this.group = snap.g()
    this.wire_group = snap.g()
    this.wire_group.attr({ "style": "pointer-events: none" })
    this.dots = []
  }
  DotGrid.prototype.indexToPoint = function(p){
    var dx = this.opt.dot_spacing
    var q = {}
    q.x = (p.x + 1/2) * dx
    q.y = (p.y + 1/2) * dx
    return q
  }
  DotGrid.prototype.quantize = function(p){
    var dx = this.opt.dot_spacing
    var q = {}
    q.x = quantize(p.x - dx/2, dx) + dx/2
    q.y = quantize(p.y - dx/2, dx) + dx/2
    return q
  }
  DotGrid.prototype.load = function(){
    var dots = this.dots
    var dx = dy = this.opt.dot_spacing
    var dot_radius = this.opt.dot_radius
    var x, y, i, j, u, r, a
    
    var w = this.w = window.innerWidth
    var h = this.h = window.innerHeight - $("#controls").height() - dy
    
    for (x = dx/2; x < w; x += dx) {
      a = []
      dots.push(a)
      for (y = dy/2; y < h; y += dy) {
        dot = this.group.circle(x, y, dot_radius).attr({
          fill: dot_color,
        })
        a.push(dot)
      }
    }
  }
  DotGrid.prototype.mousedown = function(touch, e){
    if (! drawing) return
    var p = environment.positionFromEvent(touch)
    var q = this.quantize(p)
    if (! this.active) {
      this.active = new Wire ({
        head: q
      })
    }
    else if (this.active.head.x == q.x && this.active.head.y == q.y) {
      return
    }
    else if (this.active) {
      (e || touch).preventDefault()
      this.active.setTail(q)
      this.active = null
    }
  }
  DotGrid.prototype.mouseup = function(e){
    if (this.active && this.active.length > 0) {
      // var q = this.quantize(environment.last_p)
      this.active.setTail(environment.last_p)
      this.active = null
    }
  }

  function Wire (opt){
    this.opt = opt
    if (opt.integer) {
      opt.head = dot_grid.indexToPoint(opt.head)
      if (opt.tail) {
        opt.tail = dot_grid.indexToPoint(opt.tail)
      }
    }
    if (opt.color && opt.color.h) {
      opt.color = Snap.hsl(opt.color.h, opt.color.s, opt.color.l)
    }
    else if (! opt.color) {
      opt.color = choice(palette)
    }
    this.length = 0
    this.head = opt.head
    var path_str = "M" + 0 + "," + 0
    this.path = dot_grid.wire_group.path(path_str).attr({
      stroke: opt.color,
      fill: "none",
      strokeWidth: 3,
    })
    if (opt.tail) {
      this.setTail(opt.tail, true)
    }
  }
  Wire.prototype.update = function(opt){
    var p = opt.point
    var length = this.length = dist(this.head.x, this.head.y, p.x, p.y)
    var theta = angle(this.head.x, this.head.y, p.x, p.y) * 180 / Math.PI
    var index = Math.floor( length / dot_grid.opt.dot_spacing )
    if (index < 0) return
    var length = this.length = (index * dot_grid.opt.dot_spacing)
    var q = {
      x: Math.sin(theta) * length + this.head.x,
      y: Math.cos(theta) * length + this.head.y,
    }
    // var q = dot_grid.quantize(p)
    var path_str = "M" + 0 + "," + 0
                 + "t" + length.toFixed(2) + "," + 0
    var tran_str = "translate(" + this.head.x + "," + this.head.y + ") "
                 + "rotate(" + theta + ")"
    var color = this.updateColor()
    this.path.attr({
      d: path_str,
      transform: tran_str,
      stroke: color,
    })
    if (! opt.muted && length > 0) {
      this.play(opt)
    }
    return length
  }
  Wire.prototype.updateColor = function(should_set){
    var index = this.index()
    var color = Snap.hsl(mod(index / tet * 240 + 180, 360), 100, 50)
    if (should_set) {
      this.path.attr({
        stroke: color,
      })
    }
    return color
  }
  Wire.prototype.setTail = function(p, muted){
    this.tail = p
    this.update({ point: p, muted: true })
    wires.push(this)
  }
  Wire.prototype.intersect = function (a,b) {
    if (a.x - b.x == 0 || a.y - b.y == 0) return
    if (doLineSegmentsIntersect(a, b, this.head, this.tail)) {
      this.play()
    }
  }
  Wire.prototype.index = function(){
    // var f = this.length / 340.29 * root
    // return environment.quantize( f, true )
    return environment.quantize_index( this.length / dot_grid.opt.dot_spacing )
  }
  Wire.prototype.frequency = function(){
    var f
    if (use_scale) {
      f = environment.index_to_frequency( this.length / dot_grid.opt.dot_spacing - 1 )
      // f = environment.quantize_frequency(f)
    }
    else {
      f = this.length / 340.29 * root
    }
    return f
  }
  Wire.prototype.play = function(opt){
    opt = opt || {}
    var d = opt.duration || duration
    // console.log(d, duration)
    // var f = this.length / 340.29 * root
    var f = this.frequency()
    if (opt.moving && last_f == f) {
      return
    }
    last_f = f
    // console.log(f, duration)
    polysynth.triggerAttackRelease(f, d || randrange(1.0, 2.5))
  }
  var last_f = 0
  Wire.prototype.remove = function(dont_splice){
    this.path.remove()
    if (! dont_splice) {
      wires.splice(wires.indexOf(this), 1)    
    }
  }

  environment.update = function(t){
  }
  
  var keys 
  var keys = {}
  var key_numbers = {}
  var letters = "qwertyuiop[]\\asdfghjkl;'zxcvbnm,./"
  var numbers = "1234567890";
  letters.toUpperCase().split("").map(function(k,i){
    keys[k.charCodeAt(0)] = i
  })
  numbers.split("").map(function(k,i){
    keys[k.charCodeAt(0)] = true
    key_numbers[k.charCodeAt(0)] = true
  })

  function parseInterval (s){
    if (typeof s == "number") return s
    if (! s.indexOf("/") == -1) return parseInt(s)
    var pp = s.split("/")
    var num = parseInt(pp[0])
    var den = parseInt(pp[1])
    if (isNaN(num)) return 2
    if (isNaN(den) || den == 0) return num
    if (num == den) return 2
    if (num < den) return den/num
    return num / den
  }

  return environment

})()