/*
  usage:
  
    base.mouse = new mouse({
      el: document.querySelector("#map"),
      down: function(e, cursor){
        // do something with val
        // cursor.x.a
        // cursor.y.a
      },
      move: function(e, cursor){
        // var delta = cursor.delta()
        // delta.a (x)
        // delta.b (y)
      },
      up: function(e, cursor, new_cursor){
        // cursor.x.a
        // cursor.y.a
      },
    })

*/

function mouse (opt) {
  var base = this

  opt = defaults(opt, {
    el: null,
    down: null,
    move: null,
    drag: null,
    enter: null,
    up: null,
    rightclick: null,
    propagate: false,
    locked: false,
    use_offset: true,
    val: 0,
  })
  
  base.down = false

  base.creating = false
  base.dragging = false

  base.cursor = new Rect(0,0,0,0)

  base.tube = new Tube ()
  opt.down && base.tube.on("down", opt.down)
  opt.move && base.tube.on("move", opt.move)
  opt.drag && base.tube.on("drag", opt.drag)
  opt.enter && base.tube.on("enter", opt.enter)
  opt.leave && base.tube.on("leave", opt.leave)
  opt.up && base.tube.on("up", opt.up)
  opt.rightclick && base.tube.on("rightclick", opt.rightclick)
  
  var offset = (opt.use_offset && opt.el) ? opt.el.getBoundingClientRect() : null
  
  base.init = function (){
    base.bind()
  }

  base.on = function(){
    base.tube.on.apply(base.tube, arguments)
  }

  base.off = function(){
    base.tube.off.apply(base.tube, arguments)
  }

  base.bind = function(){
    if (opt.el) {
      opt.el.addEventListener("mousedown", base.mousedown)
      opt.el.addEventListener("contextmenu", base.contextmenu)
    }
    window.addEventListener("mousemove", base.mousemove)
    window.addEventListener("mouseup", base.mouseup)
  }

  base.bind_el = function(el){
    el.addEventListener("mousedown", base.mousedown)
    el.addEventListener("mousemove", base.mousemove)
  }
  base.unbind_el = function(el){
    el.removeEventListener("mousedown", base.mousedown)
    el.removeEventListener("mousemove", base.mousemove)
  }

  function positionFromMouse(e) {
    if (offset) {
      return new vec2(offset.left - e.pageX, e.pageY - offset.top)
    }
    else {
      return new vec2(e.pageX, e.pageY)
    }
  }
  
  base.mousedown = function(e){
    if (opt.use_offset) {
      offset = this.getBoundingClientRect()
    }
    
    var pos = positionFromMouse(e)
    
    var x = pos.a, y = pos.b
    base.cursor = new Rect (x,y, x,y)
    base.down = true
    e.clickAccepted = true
    
    base.tube("down", e, base.cursor)

    if (e.clickAccepted) {
      e.stopPropagation()
    }
    else {
      base.down = false
    }
  }
  base.mousemove = function(e){
    if (opt.use_offset && ! offset) return
    
    var pos = positionFromMouse(e)

    if (e.shiftKey) {
      pos.quantize(10)
    }

    var x = pos.a, y = pos.b
    
    if (base.down) {
      base.cursor.x.b = x
      base.cursor.y.b = y
      base.tube("drag", e, base.cursor)
      e.stopPropagation()
    }
    else {
      base.cursor.x.a = base.cursor.x.b = x
      base.cursor.y.a = base.cursor.y.b = y
      base.tube("move", e, base.cursor)
    }
  }
  base.mouseenter = function(e, target, index){
    if (! base.down) return
    if (opt.use_offset && ! offset) return
    base.tube("enter", e, target, base.cursor)
  }
  base.mouseleave = function(e, target){
    if (! base.down) return
    if (opt.use_offset && ! offset) return
    base.tube("leave", e, target, base.cursor)
  }
  base.mouseup = function(e){    
    var pos, new_cursor
    
    if (base.down) {
      e.stopPropagation()
      base.down = false
      pos = positionFromMouse(e)
      new_cursor = new Rect (pos.a, pos.b)
      base.tube("up", e, base.cursor, new_cursor)
      base.cursor = new_cursor
    }
  }
  base.contextmenu = function(e){
    e.preventDefault()
    base.tube("rightclick", e, base.cursor)
  }

  base.init()
}