/*
* jQuery UI Position 1.8.4
*
* Copyright 2010, AUTHORS.txt (http://jqueryui.com/about)
* Dual licensed under the MIT or GPL Version 2 licenses.
* http://jquery.org/license
*
* http://docs.jquery.com/UI/Position
*/
(function($, undefined) {

    $.ui = $.ui || {};

    var horizontalPositions = /left|center|right/,
	horizontalDefault = "center",
	verticalPositions = /top|center|bottom/,
	verticalDefault = "center",
	_position = $.fn.position,
	_offset = $.fn.offset;

    $.fn.position = function(options) {
        if (!options || !options.of) {
            return _position.apply(this, arguments);
        }

        // make a copy, we don't want to modify arguments
        options = $.extend({}, options);

        var target = $(options.of),
		collision = (options.collision || "flip").split(" "),
		offset = options.offset ? options.offset.split(" ") : [0, 0],
		targetWidth,
		targetHeight,
		basePosition;

        if (options.of.nodeType === 9) {
            targetWidth = target.width();
            targetHeight = target.height();
            basePosition = { top: 0, left: 0 };
        } else if (options.of.scrollTo && options.of.document) {
            targetWidth = target.width();
            targetHeight = target.height();
            basePosition = { top: target.scrollTop(), left: target.scrollLeft() };
        } else if (options.of.preventDefault) {
            // force left top to allow flipping
            options.at = "left top";
            targetWidth = targetHeight = 0;
            basePosition = { top: options.of.pageY, left: options.of.pageX };
        } else {
            targetWidth = target.outerWidth();
            targetHeight = target.outerHeight();
            basePosition = target.offset();
        }

        // force my and at to have valid horizontal and veritcal positions
        // if a value is missing or invalid, it will be converted to center 
        $.each(["my", "at"], function() {
            var pos = (options[this] || "").split(" ");
            if (pos.length === 1) {
                pos = horizontalPositions.test(pos[0]) ?
				pos.concat([verticalDefault]) :
				verticalPositions.test(pos[0]) ?
					[horizontalDefault].concat(pos) :
					[horizontalDefault, verticalDefault];
            }
            pos[0] = horizontalPositions.test(pos[0]) ? pos[0] : horizontalDefault;
            pos[1] = verticalPositions.test(pos[1]) ? pos[1] : verticalDefault;
            options[this] = pos;
        });

        // normalize collision option
        if (collision.length === 1) {
            collision[1] = collision[0];
        }

        // normalize offset option
        offset[0] = parseInt(offset[0], 10) || 0;
        if (offset.length === 1) {
            offset[1] = offset[0];
        }
        offset[1] = parseInt(offset[1], 10) || 0;

        if (options.at[0] === "right") {
            basePosition.left += targetWidth;
        } else if (options.at[0] === horizontalDefault) {
            basePosition.left += targetWidth / 2;
        }

        if (options.at[1] === "bottom") {
            basePosition.top += targetHeight;
        } else if (options.at[1] === verticalDefault) {
            basePosition.top += targetHeight / 2;
        }

        basePosition.left += offset[0];
        basePosition.top += offset[1];

        return this.each(function() {
            var elem = $(this),
			elemWidth = elem.outerWidth(),
			elemHeight = elem.outerHeight(),
			position = $.extend({}, basePosition);

            if (options.my[0] === "right") {
                position.left -= elemWidth;
            } else if (options.my[0] === horizontalDefault) {
                position.left -= elemWidth / 2;
            }

            if (options.my[1] === "bottom") {
                position.top -= elemHeight;
            } else if (options.my[1] === verticalDefault) {
                position.top -= elemHeight / 2;
            }

            // prevent fractions (see #5280)
            position.left = parseInt(position.left);
            position.top = parseInt(position.top);

            $.each(["left", "top"], function(i, dir) {
                if ($.ui.position[collision[i]]) {
                    $.ui.position[collision[i]][dir](position, {
                        targetWidth: targetWidth,
                        targetHeight: targetHeight,
                        elemWidth: elemWidth,
                        elemHeight: elemHeight,
                        offset: offset,
                        my: options.my,
                        at: options.at
                    });
                }
            });

            if ($.fn.bgiframe) {
                elem.bgiframe();
            }
            elem.offset($.extend(position, { using: options.using }));
        });
    };

    $.ui.position = {
        fit: {
            left: function(position, data) {
                var win = $(window),
				over = position.left + data.elemWidth - win.width() - win.scrollLeft();
                position.left = over > 0 ? position.left - over : Math.max(0, position.left);
            },
            top: function(position, data) {
                var win = $(window),
				over = position.top + data.elemHeight - win.height() - win.scrollTop();
                position.top = over > 0 ? position.top - over : Math.max(0, position.top);
            }
        },

        flip: {
            left: function(position, data) {
                if (data.at[0] === "center") {
                    return;
                }
                var win = $(window),
				over = position.left + data.elemWidth - win.width() - win.scrollLeft(),
				myOffset = data.my[0] === "left" ?
					-data.elemWidth :
					data.my[0] === "right" ?
						data.elemWidth :
						0,
				offset = -2 * data.offset[0];
                position.left += position.left < 0 ?
				myOffset + data.targetWidth + offset :
				over > 0 ?
					myOffset - data.targetWidth + offset :
					0;
            },
            top: function(position, data) {
                if (data.at[1] === "center") {
                    return;
                }
                var win = $(window),
				over = position.top + data.elemHeight - win.height() - win.scrollTop(),
				myOffset = data.my[1] === "top" ?
					-data.elemHeight :
					data.my[1] === "bottom" ?
						data.elemHeight :
						0,
				atOffset = data.at[1] === "top" ?
					data.targetHeight :
					-data.targetHeight,
				offset = -2 * data.offset[1];
                position.top += position.top < 0 ?
				myOffset + data.targetHeight + offset :
				over > 0 ?
					myOffset + atOffset + offset :
					0;
            }
        }
    };

    // offset setter from jQuery 1.4
    if (!$.offset.setOffset) {
        $.offset.setOffset = function(elem, options) {
            // set position first, in-case top/left are set even on static elem
            if (/static/.test($.curCSS(elem, "position"))) {
                elem.style.position = "relative";
            }
            var curElem = $(elem),
			curOffset = curElem.offset(),
			curTop = parseInt($.curCSS(elem, "top", true), 10) || 0,
			curLeft = parseInt($.curCSS(elem, "left", true), 10) || 0,
			props = {
			    top: (options.top - curOffset.top) + curTop,
			    left: (options.left - curOffset.left) + curLeft
			};

            if ('using' in options) {
                options.using.call(elem, props);
            } else {
                curElem.css(props);
            }
        };

        $.fn.offset = function(options) {
            var elem = this[0];
            if (!elem || !elem.ownerDocument) { return null; }
            if (options) {
                return this.each(function() {
                    $.offset.setOffset(this, options);
                });
            }
            return _offset.call(this);
        };
    }

} (jQuery));