// ### Used by nearly every other module

//
SVG.Element = function(node) {
  /* initialize attribute store with defaults */
  this.attrs = {
    'fill-opacity':   1
  , 'stroke-opacity': 1
  , 'stroke-width':   0
  , fill:     '#000'
  , stroke:   '#000'
  , opacity:  1
  , x:        0
  , y:        0
  , cx:       0
  , cy:       0
  , width:    0
  , height:   0
  , r:        0
  , rx:       0
  , ry:       0
  }
  
  /* initialize style store */
  this.styles = {}
  
  /* initialize transformation store with defaults */
  this.trans = {
    x:        0
  , y:        0
  , scaleX:   1
  , scaleY:   1
  , rotation: 0
  , skewX:    0
  , skewY:    0
  }
  
  /* keep reference to the element node */
  if (this.node = node) {
    this.type = node.nodeName
    this.attrs.id = node.getAttribute('id')
  }
}

//
SVG.extend(SVG.Element, {
  // Move element to given x and y values
  move: function(x, y) {
    return this.attr({
      x: x
    , y: y
    })
  }
  // Move element by its center
, center: function(x, y) {
    var box = this.bbox()
    
    return this.move(x - box.width / 2, y - box.height / 2)
  }
  // Set element size to given width and height
, size: function(width, height) { 
    return this.attr({
      width:  width
    , height: height
    })
  }
  // Clone element
, clone: function() {
    var clone
    
    /* if this is a wrapped shape */
    if (this instanceof SVG.Wrap) {
      /* build new wrapped shape */
      clone = this.parent[this.child.node.nodeName]()
      clone.attrs = this.attrs
      
      /* copy child attributes and transformations */
      clone.child.trans = this.child.trans
      clone.child.attr(this.child.attrs).transform({})
      
      /* re-plot shape */
      if (clone.plot)
        clone.plot(this.child.attrs[this.child instanceof SVG.Path ? 'd' : 'points'])
      
    } else {
      var name = this.node.nodeName
      
      /* invoke shape method with shape-specific arguments */
      clone = name == 'rect' ?
        this.parent[name](this.attrs.width, this.attrs.height) :
      name == 'ellipse' ?
        this.parent[name](this.attrs.rx * 2, this.attrs.ry * 2) :
      name == 'image' ?
        this.parent[name](this.src) :
      name == 'text' ?
        this.parent[name](this.content) :
      name == 'g' ?
        this.parent.group() :
        this.parent[name]()
      
      clone.attr(this.attrs)
    }
    
    /* copy transformations */
    clone.trans = this.trans
    
    /* apply attributes and translations */
    return clone.transform({})
  }
  // Remove element
, remove: function() {
    if (this.parent)
      this.parent.remove(this)
    
    return this
  }
  // Get parent document
, doc: function() {
    return this._parent(SVG.Doc)
  }
  // Get parent nested document
, nested: function() {
    return this._parent(SVG.Nested)
  }
  // Set svg element attribute
, attr: function(a, v, n) {
    if (arguments.length < 2) {
      /* apply every attribute individually if an object is passed */
      if (typeof a == 'object')
        for (v in a)
          this.attr(v, a[v])
      
      /* act as a getter for style attributes */
      else if (this._isStyle(a))
        return a == 'text' ?
                 this.content :
               a == 'leading' ?
                 this.leading() :
                 this.style(a)
      
      /* act as a getter if the first and only argument is not an object */
      else
        return this.attrs[a] || this.node.getAttribute(a)
    
    } else if (v === null) {
      /* remove value */
      this.node.removeAttribute(a)
      
    } else if (a == 'style') {
      /* redirect to the style method */
      return this.style(v)
      
    } else {
      /* store value */
      this.attrs[a] = v
      
      /* treat x differently on text elements */
      if (a == 'x' && this._isText()) {
        for (var i = this.lines.length - 1; i >= 0; i--)
          this.lines[i].attr(a, v)
      
      /* set the actual attribute */
      } else {
        /* BUG FIX: some browsers will render a stroke if a color is given even though stroke width is 0 */
        if (a == 'stroke-width')
          this.attr('stroke', parseFloat(v) > 0 ? this.attrs.stroke : null)
        
        /* ensure hex color */
        if (SVG.Color.test(v) || SVG.Color.isRgb(v) || SVG.Color.isHsb(v))
          v = new SVG.Color(v).toHex()
          
        /* set give attribute on node */
        n != null ?
          this.node.setAttributeNS(n, a, v) :
          this.node.setAttribute(a, v)
      }
      
      /* if the passed argument belongs to the style as well, add it there */
      if (this._isStyle(a)) {
        a == 'text' ?
          this.text(v) :
        a == 'leading' ?
          this.leading(v) :
          this.style(a, v)
        
        /* rebuild if required */
        if (this.rebuild)
          this.rebuild()
      }
    }
    
    return this
  }
  // Manage transformations
, transform: function(o, v) {
    if (typeof o === 'string') {
      /* act as a getter if only one string argument is given */
      if (arguments.length < 2)
        return this.trans[o]
      
      /* apply transformations as object if key value arguments are given*/
      var transform = {}
      transform[o] = v
      
      return this.transform(transform)
    }
    
    /* ... otherwise continue as a setter */
    var transform = []
    
    /* merge values */
    for (v in o)
      if (o[v] != null)
        this.trans[v] = o[v]
    
    /* alias current transformations */
    o = this.trans
    
    /* add rotation */
    if (o.rotation != 0) {
      transform.push(
        'rotate(' + o.rotation + ','
      + (o.cx != null ? o.cx : this.bbox().cx) + ','
      + (o.cy != null ? o.cy : this.bbox().cy) + ')'
      )
    }
    
    /* add scale */
    transform.push('scale(' + o.scaleX + ',' + o.scaleY + ')')
    
    /* add skew on x axis */
    if (o.skewX != 0)
      transform.push('skewX(' + o.skewX + ')')
    
    /* add skew on y axis */
    if (o.skewY != 0)
      transform.push('skewY(' + o.skewY + ')')
    
    /* add translation */
    transform.push('translate(' + o.x + ',' + o.y + ')')
    
    /* add only te required transformations */
    return this.attr('transform', transform.join(' '))
  }
  // Dynamic style generator
, style: function(s, v) {
    if (arguments.length == 0) {
      /* get full style */
      return this.attr('style')
    
    } else if (arguments.length < 2) {
      /* apply every style individually if an object is passed */
      if (typeof s == 'object') {
        for (v in s) this.style(v, s[v])
      
      } else if (SVG.regex.isCss.test(s)) {
        /* parse css string */
        s = s.split(';')

        /* apply every definition individually */
        for (var i = 0; i < s.length; i++) {
          v = s[i].split(':')

          if (v.length == 2)
            this.style(v[0].replace(/\s+/g, ''), v[1].replace(/^\s+/,'').replace(/\s+$/,''))
        }
      } else {
        /* act as a getter if the first and only argument is not an object */
        return this.styles[s]
      }
    
    } else if (v === null) {
      /* remove value */
      delete this.styles[s]
      
    } else {
      /* store value */
      this.styles[s] = v
    }
    
    /* rebuild style string */
    s = ''
    for (v in this.styles)
      s += v + ':' + this.styles[v] + ';'
    
    /* apply style */
    this.node.setAttribute('style', s)
    
    return this
  }
  // Store data values on svg nodes
, data: function(a, v, r) {
    if (arguments.length < 2) {
      try {
        return JSON.parse(this.attr('data-' + a))
      } catch(e) {
        return this.attr('data-' + a)
      }
      
    } else {
      this.attr('data-' + a, v === null ? null : r === true ? v : JSON.stringify(v))
    }
    
    return this
  }
  // Get bounding box
, bbox: function() {
    return new SVG.BBox(this)
  }
  // Checks whether the given point inside the bounding box of the element
, inside: function(x, y) {
    var box = this.bbox()
    
    return x > box.x
        && y > box.y
        && x < box.x + box.width
        && y < box.y + box.height
  }
  // Show element
, show: function() {
    return this.style('display', '')
  }
  // Hide element
, hide: function() {
    return this.style('display', 'none')
  }
  // Is element visible?
, visible: function() {
    return this.style('display') != 'none'
  }
  // Private: find svg parent by instance
, _parent: function(parent) {
    var element = this
    
    while (element != null && !(element instanceof parent))
      element = element.parent

    return element
  }
  // Private: tester method for style detection
, _isStyle: function(attr) {
    return typeof attr == 'string' ? SVG.regex.isStyle.test(attr) : false
  }
  // Private: element type tester
, _isText: function() {
    return this instanceof SVG.Text
  }
  
})