// Poly points array
SVG.PointArray = function(array, fallback) {
  this.constructor.call(this, array, fallback || [[0,0]])
}

// Inherit from SVG.Array
SVG.PointArray.prototype = new SVG.Array

SVG.extend(SVG.PointArray, {
  // Convert array to string
  toString: function() {
    // convert to a poly point string
    for (var i = 0, il = this.value.length, array = []; i < il; i++)
      array.push(this.value[i].join(','))

    return array.join(' ')
  }
  // Convert array to line object
, toLine: function() {
    return {
      x1: this.value[0][0]
    , y1: this.value[0][1]
    , x2: this.value[1][0]
    , y2: this.value[1][1]
    }
  }
  // Get morphed array at given position
, at: function(pos) {
    // make sure a destination is defined
    if (!this.destination) return this

    // generate morphed point string
    for (var i = 0, il = this.value.length, array = []; i < il; i++)
      array.push([
        this.value[i][0] + (this.destination[i][0] - this.value[i][0]) * pos
      , this.value[i][1] + (this.destination[i][1] - this.value[i][1]) * pos
      ])

    return new SVG.PointArray(array)
  }
  // Parse point string
, parse: function(array) {
    var points = []

    array = array.valueOf()

    // if already is an array, no need to parse it
    if (Array.isArray(array)) return array

    // parse points
    array = array.trim().split(/\s+|,/)

    // validate points - https://svgwg.org/svg2-draft/shapes.html#DataTypePoints
    // Odd number of coordinates is an error. In such cases, drop the last odd coordinate.
    if (array.length % 2 !== 0) array.pop()

    // wrap points in two-tuples and parse points as floats
    for(var i = 0, len = array.length; i < len; i = i + 2)
      points.push([ parseFloat(array[i]), parseFloat(array[i+1]) ])

    return points
  }
  // Move point string
, move: function(x, y) {
    var box = this.bbox()

    // get relative offset
    x -= box.x
    y -= box.y

    // move every point
    if (!isNaN(x) && !isNaN(y))
      for (var i = this.value.length - 1; i >= 0; i--)
        this.value[i] = [this.value[i][0] + x, this.value[i][1] + y]

    return this
  }
  // Resize poly string
, size: function(width, height) {
    var i, box = this.bbox()

    // recalculate position of all points according to new size
    for (i = this.value.length - 1; i >= 0; i--) {
      this.value[i][0] = ((this.value[i][0] - box.x) * width)  / box.width  + box.x
      this.value[i][1] = ((this.value[i][1] - box.y) * height) / box.height + box.y
    }

    return this
  }
  // Get bounding box of points
, bbox: function() {
    SVG.parser.poly.setAttribute('points', this.toString())

    return SVG.parser.poly.getBBox()
  }

})