# Source: jquery.position.js

    /**
     * @fileOverview jQuery setPosition Plugin to place elements on the page
     * @author Pavel Yaschenko, 05.2010
     * @version 0.5
     */

    // draft examples of usage
    // jQuery('#tooltip').setPosition('#aaa',{from:'bottom-left', to:'auto-auto'});
    // jQuery('#bbb').bind("click",function(e){jQuery('#tooltip').setPosition(e);});
    // TODO: clear code
    // TODO: optimization

    // jQuery(target).setPosition(source,[params])
    // source:
    //			jQuery selector
    //			object {id:}
    //			object {left:,top:,width:,height} // all properties are optimal
    //			jQuery object
    //			dom element
    //			event
    //
    //	params:
    //			type: string // position type
    //			collision: string // not implemented
    //			offset: array [x,y] // implemented only for noPositionType
    //			from: string // place target relative of source
    //			to: string // direction for target

    	/**
    	  * @name jQuery
    	  * @namespace jQuery
    	  * */

    (function($) {
    	/**
         * Place DOM element relative to another element or using position parameters. Elements with style.display='none' also supported.
         *
         * @example jQuery('#tooltip').setPosition('#myDiv',{from:'LB', to:'AA'});
         * @example jQuery('#myClickDiv').bind("click",function(e){jQuery('#tooltip').setPosition(e);});
         *
         * @function
         * @name jQuery#setPosition
         *
         * @param {object} source - object that provides information about new position. <p>
         * accepts:
         * <ul>
         * 		<li>jQuery selector or object</li>
         * 		<li>object with id: <code>{id:'myDiv'}</code></li>
         * 		<li>object with region settings: <code>{left:0, top:0, width:100, height:100}</code></li>
         * 		<li>DOM Element</li>
         * 		<li>Event object</li>
         * </ul>
         * </p>
         * @param {object} params - position parameters:
         * <dl><dt>
         * @param {string} [params.type] - position type that defines positioning and auto positioning rules ["TOOLTIP","DROPDOWN"]</dt><dt>
         * @param {string} [params.collision] - not implemented yet</dt><dt>
         * @param {array} [params.offset] - provides array(2) with x and y for manually position definition<br/>
         * affects only if "type", "from" and "to" not defined</dt><dt>
         * @param {string} [params.from] - place target relative of source // draft definition</dt><dt>
         * @param {string} [params.to] - direction for target // draft definition</dt>
         * </blockquote>
         *
         * @return {jQuery} jQuery wrapped DOM elements
         * */
    	$.fn.setPosition = function(source, params) {
    		var stype = typeof source;
    		if (stype == "object" || stype == "string") {
    			var rect = {};
    			if (stype == "string" || source.nodeType || source instanceof jQuery || typeof source.length!="undefined") {
    					rect = getElementRect(source);
    			} else if (source.type) {
    				rect = getPointerRect(source);
    			} else if (source.id) {
    				rect = getElementRect(document.getElementById(source.id));
    			} else {
    				rect = source;
    			}

    			var params = params || {};
    			var def = params.type || params.from || params.to ? $.PositionTypes[params.type || defaultType] : {noPositionType:true};

    			var options =  $.extend({}, defaults, def, params);
    			if (!options.noPositionType) {
    				if (options.from.length>2) {
    					options.from = positionDefinition[options.from.toLowerCase()];
    				}
    				if (options.to.length>2) {
    					options.to = positionDefinition[options.to.toLowerCase()];
    				}
    			}
    			return this.each(function() {
    					element = $(this);
    					//alert(rect.left+" "+rect.top+" "+rect.width+" "+rect.height);
    					position(rect, element, options);
    				});
    		}
    		return this;
    	};

    	var defaultType = "TOOLTIP";
    	var defaults = {
    		collision: "",
    		offset: [0,0]
    	};
    	var re = /^(left|right)-(top|buttom|auto)$/i;

    	// TODO: make it private
    	var positionDefinition = {
    		'top-left':'LT',
    		'top-right':'RT',
    		'bottom-left':'LB',
    		'bottom-right':'RB',
    		'top-auto':'AT',
    		'bottom-auto':'AB',
    		'auto-left':'LA',
    		'auto-right':'RA',
    		'auto-auto':'AA'
    	};
    	$.PositionTypes = {
    		// horisontal constants: L-left, R-right, C-center, A-auto
    		// vertical constants:   T-top, B-bottom, M-middle, A-auto
    		// for auto: list of joinPoint-Direction pairs
    		TOOLTIP: {from:"AA", to:"AA", auto:["RTRT", "RBRT", "LTRT", "RTLT", "LTLT", "LBLT", "RTRB", "RBRB", "LBRB", "RBLB"]},
    		DROPDOWN:{from:"AA", to:"AA", auto:["LBRB", "LTRT", "RBLB", "RTLT"]},
            DDMENUGROUP:{from:"AA", to:"AA", auto:["RTRB", "RBRT", "LTLB", "LBLT"]}
    	};

    	/**
    	  * Add or replace position type rules for auto positioning.
    	  * Does not fully determinated with parameters yet, only draft version.
    	  *
    	  * @function
    	  * @name jQuery.addPositionType
    	  * @param {string} type - name of position rules
    	  * @param {object} option - options of position rules
    	  * */
    	$.addPositionType = function (type, options) {
    		// TODO: change [options] to [from, to, auto]
    		/*var obj = {};
    		if (match=from.match(re))!=null ) {
    			obj.from = [ match[1]=='right' ? 'R' : 'L', match[2]=='bottom' ? 'B' : 'T'];
    		}
    		if (match=to.match(re))!=null ) {
    			obj.to = [ match[1]=='right' ? 'R' : match[1]=='left' ? 'L' : 'A', match[2]=='bottom' ? 'B' : match[2]=='top' ? 'T' : 'A'];
    		}*/
    		$.PositionTypes[type] = options;
    	}

        function getPointerRect (event) {
    		var e = $.event.fix(event);
    		return {width: 0, height: 0, left: e.pageX, top: e.pageY};
    	};

    	function getElementRect (element) {
    		var jqe = $(element);
    		var offset = jqe.offset();
    		var rect = {width: jqe.outerWidth(), height: jqe.outerHeight(), left: Math.floor(offset.left), top: Math.floor(offset.top)};
    		if (jqe.length>1) {
    			var width, height, offset;
    			var e;
    			for (var i=1;i<jqe.length;i++) {
    				e = jqe.eq(i);
    				if (e.css('display')=="none") continue;
    				width = e.outerWidth();
    				height = e.outerHeight();
    				offset = e.offset();
    				var d = rect.left - offset.left;
    				if (d<0) {
    					if (width-d > rect.width) rect.width = width - d;
    				} else {
    					rect.width += d;
    				}
    				var d = rect.top - offset.top;
    				if (d<0) {
    					if (height-d > rect.height) rect.height = height -d;
    				} else {
    					rect.height += d;
    				}
    				if (offset.left < rect.left) rect.left = offset.left;
    				if (offset.top < rect.top) rect.top = offset.top;
    			}
    		}

    		return rect;
    	};

    	function checkCollision (elementRect, windowRect) {
    		// return 0 if elementRect in windowRect without collision
    		if (elementRect.left >= windowRect.left &&
    			elementRect.top >= windowRect.top &&
    			elementRect.right <= windowRect.right &&
    			elementRect.bottom <= windowRect.bottom)
    			return 0;
    		// return collision squire
    		var rect = {left:   (elementRect.left>windowRect.left ? elementRect.left : windowRect.left),
    					top:    (elementRect.top>windowRect.top ? elementRect.top : windowRect.top)};
    		rect.right = elementRect.right<windowRect.right ? (elementRect.right==elementRect.left ? rect.left : elementRect.right) : windowRect.right;
    		rect.bottom = elementRect.bottom<windowRect.bottom ? (elementRect.bottom==elementRect.top ? rect.top : elementRect.bottom) : windowRect.bottom;

    		return (rect.right-rect.left) * (rect.bottom-rect.top);
    	};

    	//function fromLeft() {
    	/*
    	 * params: {
    	 * 	left,top,width,height, //baseRect
    	 * 	ox,oy, //rectoffset
    	 * 	w,h // elementDim
    	 * }
    	 */
    	/*	return this.left;
    	}

    	function fromRight(params) {
    			return this.left + this.width - this.w;
    	}

    	function (params) {
    		var rect = {left:fromLeft.call(params), right:fromRight.call(params), top:}
    	}*/

    	function getPositionRect(baseRect, rectOffset, elementDim, pos) {
    		var rect = {};
    		// TODO: add support for center and middle // may be middle rename to center too

    		var v = pos.charAt(0);
    		if (v=='L') {
    			rect.left = baseRect.left;
    		} else if (v=='R') {
    			rect.left = baseRect.left + baseRect.width;
    		}

    		v = pos.charAt(1);
    		if (v=='T') {
    			rect.top = baseRect.top;
    		} else if (v=='B') {
    			rect.top = baseRect.top + baseRect.height;
    		}

    		v = pos.charAt(2);
    		if (v=='L') {
    			rect.left -= rectOffset[0];
    			rect.right = rect.left;
    			rect.left -= elementDim.width;
    		} else if (v=='R') {
    			rect.left += rectOffset[0];
    			rect.right = rect.left + elementDim.width;
    		}

    		v = pos.charAt(3);
    		if (v=='T') {
    			rect.top -= rectOffset[1];
    			rect.bottom = rect.top;
    			rect.top -= elementDim.height;
    		} else if (v=='B') {
    			rect.top += rectOffset[1];
    			rect.bottom = rect.top + elementDim.height;
    		}

    		return rect;
    	}

    	function __mergePos(s1,s2) {
    		var result = "";
    		var ch;
    		while (result.length < s1.length) {
    			ch = s1.charAt(result.length);
    			result += ch == 'A' ? s2.charAt(result.length) : ch;
    		}
    		return result;
    	}

    	function calculatePosition (baseRect, rectOffset, windowRect, elementDim, options) {

    		var theBest = {square:0};
    		var rect;
    		var s;
    		var ox, oy;
    		var p = options.from+options.to;

    		if (p.indexOf('A')<0) {
    			return getPositionRect(baseRect, rectOffset, elementDim, p);
    		} else {
    			var flag = p=="AAAA";
    			var pos;
    			for (var i = 0; i<options.auto.length; i++) {

    				// TODO: draft functional
    				pos = flag ? options.auto[i] : __mergePos(p, options.auto[i]);
    				rect = getPositionRect(baseRect, rectOffset, elementDim, pos);
    				ox = rect.left; oy = rect.top;
    				s = checkCollision(rect, windowRect);
    				if (s!=0) {
    					if (ox>=0 && oy>=0 && theBest.square<s) theBest = {x:ox, y:oy, square:s};
    				} else break;
    			}
    			if (s!=0 && (ox<0 || oy<0 || theBest.square>s)) {
    				ox=theBest.x; oy=theBest.y
    			}
    		}

    		return {left:ox, top:oy};
    	}

    	function position (rect, element, options) {
    		var width = element.width();
    		var height = element.height();

    		rect.width = rect.width || 0;
    		rect.height = rect.height || 0;

    		var left = parseInt(element.css('left'),10);
    		if (isNaN(left) || left==0) {
    			left = 0;
    			element.css('left', '0px');
    		}
    		if (isNaN(rect.left)) rect.left = left;

    		var top = parseInt(element.css('top'),10);
    		if (isNaN(top) || top==0) {
    			top = 0;
    			element.css('top', '0px');
    		}
    		if (isNaN(rect.top)) rect.top = top;

    		var pos = {};
    		if (options.noPositionType) {
    			pos.left = rect.left + rect.width + options.offset[0];
    			pos.top = rect.top + options.offset[1];
    		} else {
    			var jqw = $(window);
    			var winRect = {left:jqw.scrollLeft(), top:jqw.scrollTop()};
    			winRect.right = winRect.left + jqw.width();
    			winRect.bottom = winRect.top + jqw.height();

    			pos = calculatePosition(rect, options.offset, winRect, {width:width, height:height}, options);
    		}

    		// jQuery does not support to get offset for hidden elements
    		var hideElement=false;
    		var eVisibility;
    		var e;
    		if (element.css("display")=="none") {
    			hideElement=true;
    			e = element.get(0);
    			eVisibility = e.style.visibility;
    			e.style.visibility = 'hidden';
    			e.style.display = 'block';
    		}

    		var elementOffset = element.offset();

    		if (hideElement) {
    			e.style.visibility = eVisibility;
    			e.style.display = 'none';
    		}

    		pos.left += left - Math.floor(elementOffset.left);
    		pos.top += top - Math.floor(elementOffset.top);

    		if (left!=pos.left) {
    			element.css('left', (pos.left + 'px'));
    		}
    		if (top!=pos.top) {
    			element.css('top', (pos.top + 'px'));
    		}
    	};

    })(jQuery);