/**

*	@auth Logan Cai

*	@email cailongqun#yahoo.com.cn  (replace # with @)

*	@ this plugin is based on the nice javascript provided by http://www.jtricks.com/javascript/navigation/floating.html

*   @version 1.0

*	

*/

function floatingBox(box, options, index)

{

    this.targetX = -250;

    this.targetY =  10;

    this.interval = 0;

    this.menu = box;

    this.index = index;

    this.options = options;

    this.hasInner = typeof(window.innerWidth) == 'number';

    this.hasElement =  document.documentElement

        && document.documentElement.clientWidth;    

	this.move = function ()

	{//move function start

		jQuery(this.menu).css('left', this.nextX + 'px').css('top', this.nextY + 'px');

	};  

	this.computeShifts = function ()

	{

	    var de = document.documentElement;	

	    this.shiftX =

	        this.hasInner

	        ? pageXOffset

	        : this.hasElement

	          ? de.scrollLeft

	          : document.body.scrollLeft;

	    if (this.targetX < 0)

	    {

	        if (this.hasElement && this.hasInner)

	        {

	            // Handle Opera 8 problems

	            this.shiftX +=

	                de.clientWidth > window.innerWidth

	                ? window.innerWidth

	                : de.clientWidth

	        }

	        else

	        {

	            this.shiftX +=

	                this.hasElement

	                ? de.clientWidth

	                : this.hasInner

	                  ? window.innerWidth

	                  : document.body.clientWidth;

	        }

	    }

	

	    this.shiftY = 

	        this.hasInner

	        ? pageYOffset

	        : this.hasElement

	          ? de.scrollTop

	          : document.body.scrollTop;

	    if (this.targetY < 0)

	    {

	        if (this.hasElement && this.hasInner)

	        {

	            // Handle Opera 8 problems

	            this.shiftY +=

	                de.clientHeight > window.innerHeight

	                ? window.innerHeight

	                : de.clientHeight

	        }

	        else

	        {

	            this.shiftY +=

	                this.hasElement

	                ? document.documentElement.clientHeight

	                : this.hasInner

	                  ? window.innerHeight

	                  : document.body.clientHeight;

	        }

	    }

	};

	this.doFloat = function()

	{

	    var stepX, stepY;

	

	    this.computeShifts();

	

	    stepX = (this.shiftX + 

	        this.targetX - this.nextX) * .07;

	    if (Math.abs(stepX) < .5)

	    {

	        stepX = this.shiftX +

	            this.targetX - this.nextX;

	    }

	

	    stepY = (this.shiftY + 

	        this.targetY - this.nextY) * .07;

	    if (Math.abs(stepY) < .5)

	    {

	        stepY = this.shiftY + 

	            this.targetY - this.nextY;

	    }

	

	    if (Math.abs(stepX) > 0 ||

	        Math.abs(stepY) > 0)

	    {

	        this.nextX += stepX;

	        this.nextY += stepY;

	        this.move();

	    }

		

	    setTimeout('funcFloating[' + this.index + '].func()', this.interval);

	};	

	this.initSecondary = function()

	{

	    this.computeShifts();

	    this.nextX = this.shiftX +

	        this.targetX;

	    this.nextY = this.shiftY +

	        this.targetY;

	    this.move();

	};	

	this.position = function(targetX, targetY)

	{

		if(typeof(targetX) == 'number')

		{

			this.targetX = targetX;

		}else if(typeof(targetX) == 'string')

		{

			switch(targetX)

			{

				case 'left':

					this.targetX = 5;

					break;

				case 'right':

					this.targetX = -((jQuery(this.menu).outerWidth()) + 5);

					break;									

			}

			

		}	

		if(typeof(targetY) == 'number')

		{

			this.targetY = targetY;

		}else if(typeof(targetY) == 'string')

		{

			switch(targetY)

			{

				case 'top':

					this.targetY= 5;

					break;

				case 'bottom':



					this.targetY = -((jQuery(this.menu).outerHeight() + 5));

					

					break;								

			}

			

		}				

		

	};

	this.init = function()

	{

		jQuery(this.menu).css('position', 'absolute');

		if(typeof(this.options)  == 'object')

		{

			for(var i in this.options)

			{

				switch(i)

				{

					

					case 'targetX':

					case 'targetY':

						if(typeof(this.options[i]) == 'number')

						{

							this[i] = this.options[i];

						}else if(typeof(this.options[i]) == 'string')

						{

							switch(this.options[i])

							{

								case 'top':

									this.targetY= 5;

									break;

								case 'bottom':

									this.targetY = -((jQuery(this.menu).outerHeight() + 5));	

									break;

								case 'middle':

									this.targetY = -(0-(jQuery(this.menu).outerHeight()))/2;

									break;

								case 'left':

									this.targetX = 5;

									break;

								case 'right':

									this.targetX = -((jQuery(this.menu).outerWidth()) + 5);

									break;									

							}

							

						}

						break;	

					default:

						this[i] = this.options[i];				

				}

			}

		}		

		

	    this.initSecondary();

	    this.doFloat();

	}

		      

};



// Some browsers init scrollbars only after

// full document load.

var funcFloating = {};

jQuery.fn.floating = function(options)

{

	return jQuery(this).each(

	

		function(i)

		{		

			var nextIndex = 0;

			for(var index in funcFloating)

			{

				nextIndex = parseInt(index);

			}	

			funcFloating[nextIndex + 1] = {};	

			funcFloating[nextIndex + 1].box = this;	

			funcFloating[nextIndex + 1].obj = new floatingBox(this, options, (nextIndex + 1));

			funcFloating[nextIndex + 1].func = function(){ funcFloating[nextIndex + 1].obj.doFloat(); };

			if (document.layers)

			{

				funcFloating[nextIndex + 1].obj.init();

			}else

			{

				

				funcFloating[nextIndex + 1].obj.init();

				funcFloating[nextIndex + 1].obj.initSecondary();

			}

			

		}

	);

};

jQuery.fn.floatingPosition = function(targetX, targetY)

{

	return jQuery(this).each(

	

		function(i)

		{	

			for(var j in funcFloating)

			{

				if(funcFloating[j].box == this)

				{

					funcFloating[j].obj.position(targetX, targetY);

				}

			}

			

		}

	);	

};