/*
 * Dual licensed under the MIT (http://www.opensource.org/licenses/mit-license.php)
 * and GPL (http://www.opensource.org/licenses/gpl-license.php) licenses.
 *
 * $LastChangedDate$
 * $Rev$
 */

jQuery.fn._height = jQuery.fn.height;
jQuery.fn._width  = jQuery.fn.width;

/**
 * If used on document, returns the document's height (innerHeight)
 * If used on window, returns the viewport's (window) height
 * See core docs on height() to see what happens when used on an element.
 *
 * @example $("#testdiv").height()
 * @result 200
 *
 * @example $(document).height()
 * @result 800
 *
 * @example $(window).height()
 * @result 400
 *
 * @name height
 * @type Object
 * @cat Plugins/Dimensions
 */
jQuery.fn.height = function() {
	if ( this[0] == window )
		return self.innerHeight ||
			jQuery.boxModel && document.documentElement.clientHeight ||
			document.body.clientHeight;

	if ( this[0] == document )
		return Math.max( document.body.scrollHeight, document.body.offsetHeight );

	return this._height(arguments[0]);
};

/**
 * If used on document, returns the document's width (innerWidth)
 * If used on window, returns the viewport's (window) width
 * See core docs on height() to see what happens when used on an element.
 *
 * @example $("#testdiv").width()
 * @result 200
 *
 * @example $(document).width()
 * @result 800
 *
 * @example $(window).width()
 * @result 400
 *
 * @name width
 * @type Object
 * @cat Plugins/Dimensions
 */
jQuery.fn.width = function() {
	if ( this[0] == window )
		return self.innerWidth ||
			jQuery.boxModel && document.documentElement.clientWidth ||
			document.body.clientWidth;

	if ( this[0] == document )
		return Math.max( document.body.scrollWidth, document.body.offsetWidth );

	return this._width(arguments[0]);
};

/**
 * Returns the inner height value (without border) for the first matched element.
 * If used on document, returns the document's height (innerHeight)
 * If used on window, returns the viewport's (window) height
 *
 * @example $("#testdiv").innerHeight()
 * @result 800
 *
 * @name innerHeight
 * @type Number
 * @cat Plugins/Dimensions
 */
jQuery.fn.innerHeight = function() {
	return this[0] == window || this[0] == document ?
		this.height() :
		this.css('display') != 'none' ?
		 	this[0].offsetHeight - (parseInt(this.css("borderTopWidth")) || 0) - (parseInt(this.css("borderBottomWidth")) || 0) :
			this.height() + (parseInt(this.css("paddingTop")) || 0) + (parseInt(this.css("paddingBottom")) || 0);
};

/**
 * Returns the inner width value (without border) for the first matched element.
 * If used on document, returns the document's Width (innerWidth)
 * If used on window, returns the viewport's (window) width
 *
 * @example $("#testdiv").innerWidth()
 * @result 1000
 *
 * @name innerWidth
 * @type Number
 * @cat Plugins/Dimensions
 */
jQuery.fn.innerWidth = function() {
	return this[0] == window || this[0] == document ?
		this.width() :
		this.css('display') != 'none' ?
			this[0].offsetWidth - (parseInt(this.css("borderLeftWidth")) || 0) - (parseInt(this.css("borderRightWidth")) || 0) :
			this.height() + (parseInt(this.css("paddingLeft")) || 0) + (parseInt(this.css("paddingRight")) || 0);
};

/**
 * Returns the outer height value (including border) for the first matched element.
 * Cannot be used on document or window.
 *
 * @example $("#testdiv").outerHeight()
 * @result 1000
 *
 * @name outerHeight
 * @type Number
 * @cat Plugins/Dimensions
 */
jQuery.fn.outerHeight = function() {
	return this[0] == window || this[0] == document ?
		this.height() :
		this.css('display') != 'none' ?
			this[0].offsetHeight :
			this.height() + (parseInt(this.css("borderTopWidth")) || 0) + (parseInt(this.css("borderBottomWidth")) || 0)
				+ (parseInt(this.css("paddingTop")) || 0) + (parseInt(this.css("paddingBottom")) || 0);
};

/**
 * Returns the outer width value (including border) for the first matched element.
 * Cannot be used on document or window.
 *
 * @example $("#testdiv").outerWidth()
 * @result 1000
 *
 * @name outerWidth
 * @type Number
 * @cat Plugins/Dimensions
 */
jQuery.fn.outerWidth = function() {
	return this[0] == window || this[0] == document ?
		this.width() :
		this.css('display') != 'none' ?
			this[0].offsetWidth :
			this.height() + (parseInt(this.css("borderLeftWidth")) || 0) + (parseInt(this.css("borderRightWidth")) || 0)
				+ (parseInt(this.css("paddingLeft")) || 0) + (parseInt(this.css("paddingRight")) || 0);
};

/**
 * Returns how many pixels the user has scrolled to the right (scrollLeft).
 * Works on containers with overflow: auto and window/document.
 *
 * @example $("#testdiv").scrollLeft()
 * @result 100
 *
 * @name scrollLeft
 * @type Number
 * @cat Plugins/Dimensions
 */
jQuery.fn.scrollLeft = function() {
	if ( this[0] == window || this[0] == document )
		return self.pageXOffset ||
			jQuery.boxModel && document.documentElement.scrollLeft ||
			document.body.scrollLeft;

	return this[0].scrollLeft;
};

/**
 * Returns how many pixels the user has scrolled to the bottom (scrollTop).
 * Works on containers with overflow: auto and window/document.
 *
 * @example $("#testdiv").scrollTop()
 * @result 100
 *
 * @name scrollTop
 * @type Number
 * @cat Plugins/Dimensions
 */
jQuery.fn.scrollTop = function() {
	if ( this[0] == window || this[0] == document )
		return self.pageYOffset ||
			jQuery.boxModel && document.documentElement.scrollTop ||
			document.body.scrollTop;

	return this[0].scrollTop;
};

/**
 * Returns the location of the element in pixels from the top left corner of the viewport.
 *
 * For accurate readings make sure to use pixel values for margins, borders and padding.
 *
 * @example $("#testdiv").offset()
 * @result { top: 100, left: 100, scrollTop: 10, scrollLeft: 10 }
 *
 * @example $("#testdiv").offset({ scroll: false })
 * @result { top: 90, left: 90 }
 *
 * @example var offset = {}
 * $("#testdiv").offset({ scroll: false }, offset)
 * @result offset = { top: 90, left: 90 }
 *
 * @name offset
 * @param Object options A hash of options describing what should be included in the final calculations of the offset.
 *                       The options include:
 *                           margin: Should the margin of the element be included in the calculations? True by default.
 *                                   If set to false the margin of the element is subtracted from the total offset.
 *                           border: Should the border of the element be included in the calculations? True by default.
 *                                   If set to false the border of the element is subtracted from the total offset.
 *                           padding: Should the padding of the element be included in the calculations? False by default.
 *                                    If set to true the padding of the element is added to the total offset.
 *                           scroll: Should the scroll offsets of the parent elements be included in the calculations?
 *                                   True by default. When true, it adds the total scroll offsets of all parents to the
 *                                   total offset and also adds two properties to the returned object, scrollTop and
 *                                   scrollLeft. If set to false the scroll offsets of parent elements are ignored.
 *                                   If scroll offsets are not needed, set to false to get a performance boost.
 * @param Object returnObject An object to store the return value in, so as not to break the chain. If passed in the
 *                            chain will not be broken and the result will be assigned to this object.
 * @type Object
 * @cat Plugins/Dimensions
 * @author Brandon Aaron (brandon.aaron@gmail.com || http://brandonaaron.net)
 */
jQuery.fn.offset = function(options, returnObject) {
	var x = 0, y = 0, elem = this[0], parent = this[0], absparent=false, relparent=false, op, sl = 0, st = 0, options = jQuery.extend({ margin: true, border: true, padding: false, scroll: true }, options || {});
	do {
    if(parent == null) 
      {
      // fix by Thomas Howard , stops some javascript errors with an unknown original cause, somehow parent sometimes ends up empty
      return null;
      }
		x += parent.offsetLeft || 0;
		y += parent.offsetTop  || 0;

		// Mozilla and IE do not add the border
		if (jQuery.browser.mozilla || jQuery.browser.msie) {
			// get borders
			var bt = parseInt(jQuery.css(parent, 'borderTopWidth')) || 0;
			var bl = parseInt(jQuery.css(parent, 'borderLeftWidth')) || 0;

			// add borders to offset
			x += bl;
			y += bt;

			// Mozilla removes the border if the parent has overflow property other than visible
			if (jQuery.browser.mozilla && parent != elem && jQuery.css(parent, 'overflow') != 'visible') {
				x += bl;
				y += bt;
			}
			
			// Mozilla does not include the border on body if an element isn't positioned absolute and is without an absolute parent
			if (jQuery.css(parent, 'position') == 'absolute') absparent = true;
			// IE does not include the border on the body if an element is position static and without an absolute or relative parent
			if (jQuery.css(parent, 'position') == 'relative') relparent = true;
		}

		if (options.scroll) {
			// Need to get scroll offsets in-between offsetParents
			op = parent.offsetParent;
			do {
				sl += parent.scrollLeft || 0;
				st += parent.scrollTop  || 0;

				parent = parent.parentNode;

				// Mozilla removes the border if the parent has overflow property other than visible
				if (jQuery.browser.mozilla && parent != elem && parent != op && jQuery.css(parent, 'overflow') != 'visible') {
					x += parseInt(jQuery.css(parent, 'borderLeftWidth')) || 0;
					y += parseInt(jQuery.css(parent, 'borderTopWidth')) || 0;
				}
			} while (op && parent != op);
		} else
			parent = parent.offsetParent;

		if (parent && (parent.tagName.toLowerCase() == 'body' || parent.tagName.toLowerCase() == 'html')) {
			// Safari and IE Standards Mode doesn't add the body margin for elments positioned with static or relative
			if ((jQuery.browser.safari || (jQuery.browser.msie && jQuery.boxModel)) && jQuery.css(elem, 'position') != 'absolute') {
				x += parseInt(jQuery.css(parent, 'marginLeft')) || 0;
				y += parseInt(jQuery.css(parent, 'marginTop'))  || 0;
			}
			// Mozilla does not include the border on body if an element isn't positioned absolute and is without an absolute parent
			// IE does not include the border on the body if an element is positioned static and without an absolute or relative parent
			if ( (jQuery.browser.mozilla && !absparent) || 
			     (jQuery.browser.msie && jQuery.css(elem, 'position') == 'static' && (!relparent || !absparent)) ) {
				x += parseInt(jQuery.css(parent, 'borderLeftWidth')) || 0;
				y += parseInt(jQuery.css(parent, 'borderTopWidth'))  || 0;
			}
			break; // Exit the loop
		}
	} while (parent);

	if ( !options.margin) {
		x -= parseInt(jQuery.css(elem, 'marginLeft')) || 0;
		y -= parseInt(jQuery.css(elem, 'marginTop'))  || 0;
	}

	// Safari and Opera do not add the border for the element
	if ( options.border && (jQuery.browser.safari || jQuery.browser.opera) ) {
		x += parseInt(jQuery.css(elem, 'borderLeftWidth')) || 0;
		y += parseInt(jQuery.css(elem, 'borderTopWidth'))  || 0;
	} else if ( !options.border && !(jQuery.browser.safari || jQuery.browser.opera) ) {
		x -= parseInt(jQuery.css(elem, 'borderLeftWidth')) || 0;
		y -= parseInt(jQuery.css(elem, 'borderTopWidth'))  || 0;
	}

	if ( options.padding ) {
		x += parseInt(jQuery.css(elem, 'paddingLeft')) || 0;
		y += parseInt(jQuery.css(elem, 'paddingTop'))  || 0;
	}

	// Opera thinks offset is scroll offset for display: inline elements
	if (options.scroll && jQuery.browser.opera && jQuery.css(elem, 'display') == 'inline') {
		sl -= elem.scrollLeft || 0;
		st -= elem.scrollTop  || 0;
	}

	var returnValue = options.scroll ? { top: y - st, left: x - sl, scrollTop:  st, scrollLeft: sl }
	                                 : { top: y, left: x };

	if (returnObject) { jQuery.extend(returnObject, returnValue); return this; }
	else              { return returnValue; }
};