var SOGoDragHandlesInterface = {
  leftMargin: 180,
  topMargin: 120,
  dhType: null,
  origX: -1,
  origLeft: -1,
  origRight: -1,
  origY: -1, 
  origUpper: -1,
  origLower: -1,
  delta: -1,
  leftBlock: null,
  rightBlock: null,
  upperBlock: null,
  lowerBlock: null,
  startHandleDraggingBound: null,
  stopHandleDraggingBound: null,
  moveBound: null,
  bind: function () {
    this.startHandleDraggingBound = this.startHandleDragging.bindAsEventListener(this);
    Event.observe(this, "mousedown", this.startHandleDraggingBound, false);
  },
  _determineType: function () {
    if (this.leftBlock && this.rightBlock)
      this.dhType = 'horizontal';
    else if (this.upperBlock && this.lowerBlock)
      this.dhType = 'vertical';
  },
  startHandleDragging: function (event) {
    if (!this.dhType)
      this._determineType();
    var targ = getTarget(event);
    if (targ.nodeType == 1) {
      if (this.dhType == 'horizontal') {
        this.origX = this.offsetLeft;
        this.origLeft = this.leftBlock.offsetWidth;
	delta = 0;
        this.origRight = this.rightBlock.offsetLeft - 5;
        document.body.setStyle({ cursor: "e-resize" });
      } else if (this.dhType == 'vertical') {
        this.origY = this.offsetTop;
        this.origUpper = this.upperBlock.offsetHeight;
	var pointY = Event.pointerY(event);
	if (pointY <= this.topMargin) delta = this.topMargin;
        else delta = pointY - this.offsetTop - 5;
        this.origLower = this.lowerBlock.offsetTop - 5;
        document.body.setStyle({ cursor: "n-resize" });
      }
      this.stopHandleDraggingBound = this.stopHandleDragging.bindAsEventListener(this);
      Event.observe(document.body, "mouseup", this.stopHandleDraggingBound, true);
      this.moveBound = this.move.bindAsEventListener(this);
      Event.observe(document.body, "mousemove", this.moveBound, true);
      this.move(event);
      event.cancelBubble = true;
    }

    return false;
  },
  stopHandleDragging: function (event) {
    if (!this.dhType)
      this._determineType();
    if (this.dhType == 'horizontal') {
      var pointerX = Event.pointerX(event);
      if (pointerX <= this.leftMargin) {
	this.rightBlock.setStyle({ left: (this.leftMargin) + 'px' });
	this.leftBlock.setStyle({ width: (this.leftMargin) + 'px' });
      }
      else {
	var deltaX = Math.floor(pointerX - this.origX - (this.offsetWidth / 2));
	this.rightBlock.setStyle({ left: (this.origRight + deltaX) + 'px' });
	this.leftBlock.setStyle({ width: (this.origLeft + deltaX) + 'px' });
      }
    } else if (this.dhType == 'vertical') {
      var pointerY = Event.pointerY(event);
      if (pointerY <= this.topMargin) {
	this.lowerBlock.setStyle({ top: (this.topMargin - delta) + 'px' });
	this.upperBlock.setStyle({ height: (this.topMargin - delta) + 'px' });
      }
      else {
        var deltaY = Math.floor(pointerY - this.origY - (this.offsetHeight / 2));
	this.lowerBlock.setStyle({ top: (this.origLower + deltaY - delta) + 'px' });
	this.upperBlock.setStyle({ height: (this.origUpper + deltaY - delta) + 'px' });
      }
    }
    Event.stopObserving(document.body, "mouseup", this.stopHandleDraggingBound, true);
    Event.stopObserving(document.body, "mousemove", this.moveBound, true);
    
    document.body.setAttribute('style', '');
    
    Event.stop(event);
  },
  move: function (event) {
    if (!this.dhType)
      this._determineType();
    if (this.dhType == 'horizontal') {
      var hX =  Event.pointerX(event);
      var width = this.offsetWidth;
      if (hX < this.leftMargin)
	hX = this.leftMargin + Math.floor(width / 2);
      var newLeft = Math.floor(hX - (width / 2));
      this.setStyle({ left: newLeft + 'px' });
    } else if (this.dhType == 'vertical') {
      var height = this.offsetHeight;
      var hY = Event.pointerY(event);
      if (hY < this.topMargin)
	hY = this.topMargin + Math.floor(height / 2);
      var newTop = Math.floor(hY - (height / 2))  - delta;
      this.setStyle({ top: newTop + 'px' });
    }
    Event.stop(event);
  },
  doubleClick: function (event) {
    if (!this.dhType)
      this._determineType();
    if (this.dhType == 'horizontal') {
      var lLeft = this.leftBlock.offsetLeft;
    
      if (this.offsetLeft > lLeft) {
        var leftdelta = this.rightBlock.offsetLeft - this.offsetLeft;

        this.setStyle({ left: lLeft + 'px' });
        this.leftBlock.setStyle({ width: '0px' });
        this.rightBlock.setStyle({ left: (lLeft + leftdelta) + 'px' });
      }
    } else if (this.dhType == 'vertical') {
      var uTop = this.upperBlock.offsetTop;

      if (this.offsetTop > uTop) {
        var topdelta = this.lowerBlock.offsetTop - this.offsetTop;
      
        this.setStyle({ top: uTop + 'px' });
        this.upperBlock.setStyle({ width: '0px' });
        this.lowerBlock.setStyle({ top: (uTop + topdelta) + 'px' });
      }
    }
  }

};