var nopaint = (function(){
  
  var is_paint = false
  
  controls.nopaint = {}
  
  controls.no = new Checkbox (nopaint_no_el)
  controls.no.use = function(state){
    this.update(! nopaint.timeout)
    controls.paint.update(false)
    undo.undo()
    nopaint.play()
  }

  controls.paint = new Checkbox (nopaint_paint_el)
  controls.paint.use = function(state){
    controls.no.update(false)
    nopaint.play()
    this.update(!! nopaint.timeout)
  }
  
  // use own stepwise clock to drive tweens
  oktween.raf = function(){}  
  
  var nopaint = {}
  nopaint.delay = 100
  nopaint.tool = null
  nopaint.tools = {}
  nopaint.step = 0
  nopaint.time = 0
  nopaint.timeout = false
  nopaint.undo = function(){
    undo.undo()
  }
  nopaint.pause = function(){
    clearTimeout(nopaint.timeout)
    nopaint.timeout = 0
    nopaint.step = 0
  }
  nopaint.play = function(){
    nopaint.pause()
    nopaint.switch_tool()
    nopaint.go()
  }
  nopaint.go = function(){
    nopaint.timeout = setTimeout(nopaint.go, nopaint.delay)
    oktween.update(nopaint.time)
    nopaint.tool.paint( nopaint.step )
    nopaint.time += 1
    nopaint.step += 1
  }
  nopaint.switch_tool = function(){
    undo.new()
    last_tool = nopaint.tool
    last_tool && last_tool.finish()
    nopaint.tool = nopaint.tools[ choice(Object.keys(nopaint.tools)) ]
    nopaint.tool.start( last_tool )
    // console.log(nopaint.tool.type)
  }
  nopaint.add_tool = function(fn){
    nopaint.tools[fn.type] = fn
  }

  var NopaintTool = Model({
    type: "none",
    init: function(){},
    start: function(){},
    paint: function(t){},
    finish: function(){},
  })
  
  var NopaintBrush = NopaintTool.extend({
    type: "brush",
    is_brush: true,
    init: function(){
      this.p = {x: 0, y: 0}
      this.fg = 0
      this.bg = 1
      this.char = " "
      this.tweens = []
    },
    
    start: function(last_brush){
      this.reset( last_brush )
      this.iterate( last_brush )
      brush.load( this )
      brush.generate()
      draw.down({}, null, [this.p.x, this.p.y])
    },
    
    paint: function(t){
      this.update( t )
      draw.move_toroidal({}, null, [this.p.x, this.p.y])
    },
    
    finish: function(){
      this.tweens.forEach(function(t){ t.cancel() })
      this.tweens = []
    },
    
    reorient: function(last_brush){
      var a = {}, b
      
      if (last_brush) {
        this.p.x = a.x = randint(canvas.w)
        this.p.y = a.y = randint(canvas.h)
      }
      else {
        a.x = this.p.x
        a.y = this.p.y
      }

      b = this.get_next_point()

      var tween = oktween.add({
        obj: this.p,
        from: a,
        to: b,
        duration: b.duration,
        easing: b.easing,
        update: function(o,dt){
          // console.log(o,dt)
        },
        finished: function(){
          this.reorient()
        }.bind(this)
      })
      this.tweens.push(tween)
    },
    
    
  })
  
  var easings = "linear circ_out circ_in circ_in_out quad_in quad_out quad_in_out".split(" ")

  var SolidBrush = NopaintBrush.extend({
    type: "solid",
    
    get_next_point: function(){
      var b = {}
      b.duration = randrange(1,7)
      b.easing = choice(easings)
      b.x = this.p.x + randrange(-10, 10)
      b.y = this.p.y + randrange(-10, 10)
      return b
    },
    
    recolor: function(){
      this.fg = this.bg = randint(16)
      this.char = " "
    },
    reset: function(){
      brush.resize(1,1)
    },
    iterate: function( last_brush ){
      this.reorient( last_brush )
      this.recolor( last_brush )
    },
    update: function(t){
    }
  })
  
  nopaint.add_tool( new SolidBrush )

})()