# dom.js

    /*
    Copyright (c) 2006, Yahoo! Inc. All rights reserved.
    Code licensed under the BSD License:
    http://developer.yahoo.net/yui/license.txt
    version: 0.12.0
    */
    // holder
    /**
     * The dom module provides helper methods for manipulating Dom elements.
     * @module dom
     *
     */

    (function() {
        var Y = YAHOO.util,     // internal shorthand
            getStyle,           // for load time browser branching
            setStyle,           // ditto
            id_counter = 0,     // for use with generateId
            propertyCache = {}; // for faster hyphen converts

        // brower detection
        var ua = navigator.userAgent.toLowerCase(),
            isOpera = (ua.indexOf('opera') > -1),
            isSafari = (ua.indexOf('safari') > -1),
            isGecko = (!isOpera && !isSafari && ua.indexOf('gecko') > -1),
            isIE = (!isOpera && ua.indexOf('msie') > -1);

        // regex cache
        var patterns = {
            HYPHEN: /(-[a-z])/i
        };

        var toCamel = function(property) {
            if ( !patterns.HYPHEN.test(property) ) {
                return property; // no hyphens
            }

            if (propertyCache[property]) { // already converted
                return propertyCache[property];
            }

            while( patterns.HYPHEN.exec(property) ) {
                property = property.replace(RegExp.$1,
                        RegExp.$1.substr(1).toUpperCase());
            }

            propertyCache[property] = property;
            return property;
            //return property.replace(/-([a-z])/gi, function(m0, m1) {return m1.toUpperCase()}) // cant use function as 2nd arg yet due to safari bug
        };

        // branching at load instead of runtime
        if (document.defaultView && document.defaultView.getComputedStyle) { // W3C DOM method
            getStyle = function(el, property) {
                var value = null;

                var computed = document.defaultView.getComputedStyle(el, '');
                if (computed) { // test computed before touching for safari
                    value = computed[toCamel(property)];
                }

                return el.style[property] || value;
            };
        } else if (document.documentElement.currentStyle && isIE) { // IE method
            getStyle = function(el, property) {
                switch( toCamel(property) ) {
                    case 'opacity' :// IE opacity uses filter
                        var val = 100;
                        try { // will error if no DXImageTransform
                            val = el.filters['DXImageTransform.Microsoft.Alpha'].opacity;

                        } catch(e) {
                            try { // make sure its in the document
                                val = el.filters('alpha').opacity;
                            } catch(e) {
                            }
                        }
                        return val / 100;
                        break;
                    default:
                        // test currentStyle before touching
                        var value = el.currentStyle ? el.currentStyle[property] : null;
                        return ( el.style[property] || value );
                }
            };
        } else { // default to inline only
            getStyle = function(el, property) { return el.style[property]; };
        }

        if (isIE) {
            setStyle = function(el, property, val) {
                switch (property) {
                    case 'opacity':
                        if ( typeof el.style.filter == 'string' ) { // in case not appended
                            el.style.filter = 'alpha(opacity=' + val * 100 + ')';

                            if (!el.currentStyle || !el.currentStyle.hasLayout) {
                                el.style.zoom = 1; // when no layout or cant tell
                            }
                        }
                        break;
                    default:
                    el.style[property] = val;
                }
            };
        } else {
            setStyle = function(el, property, val) {
                el.style[property] = val;
            };
        }

        /**
         * Provides helper methods for DOM elements.
         * @namespace YAHOO.util
         * @class Dom
         */
        YAHOO.util.Dom = {
            /**
             * Returns an HTMLElement reference.
             * @method get
             * @param {String | HTMLElement |Array} el Accepts a string to use as an ID for getting a DOM reference, an actual DOM reference, or an Array of IDs and/or HTMLElements.
             * @return {HTMLElement | Array} A DOM reference to an HTML element or an array of HTMLElements.
             */
            get: function(el) {
                if (!el) { return null; } // nothing to work with

                if (typeof el != 'string' && !(el instanceof Array) ) { // assuming HTMLElement or HTMLCollection, so pass back as is
                    return el;
                }

                if (typeof el == 'string') { // ID
                    return document.getElementById(el);
                }
                else { // array of ID's and/or elements
                    var collection = [];
                    for (var i = 0, len = el.length; i < len; ++i) {
                        collection[collection.length] = Y.Dom.get(el[i]);
                    }

                    return collection;
                }

                return null; // safety, should never happen
            },

            /**
             * Normalizes currentStyle and ComputedStyle.
             * @method getStyle
             * @param {String | HTMLElement |Array} el Accepts a string to use as an ID, an actual DOM reference, or an Array of IDs and/or HTMLElements.
             * @param {String} property The style property whose value is returned.
             * @return {String | Array} The current value of the style property for the element(s).
             */
            getStyle: function(el, property) {
                property = toCamel(property);

                var f = function(element) {
                    return getStyle(element, property);
                };

                return Y.Dom.batch(el, f, Y.Dom, true);
            },

            /**
             * Wrapper for setting style properties of HTMLElements.  Normalizes "opacity" across modern browsers.
             * @method setStyle
             * @param {String | HTMLElement | Array} el Accepts a string to use as an ID, an actual DOM reference, or an Array of IDs and/or HTMLElements.
             * @param {String} property The style property to be set.
             * @param {String} val The value to apply to the given property.
             */
            setStyle: function(el, property, val) {
                property = toCamel(property);

                var f = function(element) {
                    setStyle(element, property, val);

                };

                Y.Dom.batch(el, f, Y.Dom, true);
            },

            /**
             * Gets the current position of an element based on page coordinates.  Element must be part of the DOM tree to have page coordinates (display:none or elements not appended return false).
             * @method getXY
             * @param {String | HTMLElement | Array} el Accepts a string to use as an ID, an actual DOM reference, or an Array of IDs and/or HTMLElements
             * @return {Array} The XY position of the element(s)
             */
            getXY: function(el) {
                var f = function(el) {

                // has to be part of document to have pageXY
                    if (el.parentNode === null || el.offsetParent === null ||
                            this.getStyle(el, 'display') == 'none') {
                        return false;
                    }

                    var parentNode = null;
                    var pos = [];
                    var box;

                    if (el.getBoundingClientRect) { // IE
                        box = el.getBoundingClientRect();
                        var doc = document;
                        if ( !this.inDocument(el) && parent.document != document) {// might be in a frame, need to get its scroll
                            doc = parent.document;

                            if ( !this.isAncestor(doc.documentElement, el) ) {
                                return false;
                            }

                        }

                        var scrollTop = Math.max(doc.documentElement.scrollTop, doc.body.scrollTop);
                        var scrollLeft = Math.max(doc.documentElement.scrollLeft, doc.body.scrollLeft);

                        return [box.left + scrollLeft, box.top + scrollTop];
                    }
                    else { // safari, opera, & gecko
                        pos = [el.offsetLeft, el.offsetTop];
                        parentNode = el.offsetParent;
                        if (parentNode != el) {
                            while (parentNode) {
                                pos[0] += parentNode.offsetLeft;
                                pos[1] += parentNode.offsetTop;
                                parentNode = parentNode.offsetParent;
                            }
                        }
                        if (isSafari && this.getStyle(el, 'position') == 'absolute' ) { // safari doubles in some cases
                            pos[0] -= document.body.offsetLeft;
                            pos[1] -= document.body.offsetTop;
                        }
                    }

                    if (el.parentNode) { parentNode = el.parentNode; }
                    else { parentNode = null; }

                    while (parentNode && parentNode.tagName.toUpperCase() != 'BODY' && parentNode.tagName.toUpperCase() != 'HTML')
                    { // account for any scrolled ancestors
                        if (Y.Dom.getStyle(parentNode, 'display') != 'inline') { // work around opera inline scrollLeft/Top bug
                            pos[0] -= parentNode.scrollLeft;
                            pos[1] -= parentNode.scrollTop;
                        }

                        if (parentNode.parentNode) {
                            parentNode = parentNode.parentNode;
                        } else { parentNode = null; }
                    }

                    return pos;
                };

                return Y.Dom.batch(el, f, Y.Dom, true);
            },

            /**
             * Gets the current X position of an element based on page coordinates.  The element must be part of the DOM tree to have page coordinates (display:none or elements not appended return false).
             * @method getX
             * @param {String | HTMLElement | Array} el Accepts a string to use as an ID, an actual DOM reference, or an Array of IDs and/or HTMLElements
             * @return {String | Array} The X position of the element(s)
             */
            getX: function(el) {
                var f = function(el) {
                    return Y.Dom.getXY(el)[0];
                };

                return Y.Dom.batch(el, f, Y.Dom, true);
            },

            /**
             * Gets the current Y position of an element based on page coordinates.  Element must be part of the DOM tree to have page coordinates (display:none or elements not appended return false).
             * @method getY
             * @param {String | HTMLElement | Array} el Accepts a string to use as an ID, an actual DOM reference, or an Array of IDs and/or HTMLElements
             * @return {String | Array} The Y position of the element(s)
             */
            getY: function(el) {
                var f = function(el) {
                    return Y.Dom.getXY(el)[1];
                };

                return Y.Dom.batch(el, f, Y.Dom, true);
            },

            /**
             * Set the position of an html element in page coordinates, regardless of how the element is positioned.
             * The element(s) must be part of the DOM tree to have page coordinates (display:none or elements not appended return false).
             * @method setXY
             * @param {String | HTMLElement | Array} el Accepts a string to use as an ID, an actual DOM reference, or an Array of IDs and/or HTMLElements
             * @param {Array} pos Contains X & Y values for new position (coordinates are page-based)
             * @param {Boolean} noRetry By default we try and set the position a second time if the first fails
             */
            setXY: function(el, pos, noRetry) {
                var f = function(el) {
                    var style_pos = this.getStyle(el, 'position');
                    if (style_pos == 'static') { // default to relative
                        this.setStyle(el, 'position', 'relative');
                        style_pos = 'relative';
                    }

                    var pageXY = this.getXY(el);
                    if (pageXY === false) { // has to be part of doc to have pageXY
                        return false;
                    }

                    var delta = [ // assuming pixels; if not we will have to retry
                        parseInt( this.getStyle(el, 'left'), 10 ),
                        parseInt( this.getStyle(el, 'top'), 10 )
                    ];

                    if ( isNaN(delta[0]) ) {// in case of 'auto'
                        delta[0] = (style_pos == 'relative') ? 0 : el.offsetLeft;
                    }
                    if ( isNaN(delta[1]) ) { // in case of 'auto'
                        delta[1] = (style_pos == 'relative') ? 0 : el.offsetTop;
                    }

                    if (pos[0] !== null) { el.style.left = pos[0] - pageXY[0] + delta[0] + 'px'; }
                    if (pos[1] !== null) { el.style.top = pos[1] - pageXY[1] + delta[1] + 'px'; }

                    var newXY = this.getXY(el);

                    // if retry is true, try one more time if we miss
                    if (!noRetry && (newXY[0] != pos[0] || newXY[1] != pos[1]) ) {
                        this.setXY(el, pos, true);
                    }

                };

                Y.Dom.batch(el, f, Y.Dom, true);
            },

            /**
             * Set the X position of an html element in page coordinates, regardless of how the element is positioned.
             * The element must be part of the DOM tree to have page coordinates (display:none or elements not appended return false).
             * @method setX
             * @param {String | HTMLElement | Array} el Accepts a string to use as an ID, an actual DOM reference, or an Array of IDs and/or HTMLElements.
             * @param {Int} x The value to use as the X coordinate for the element(s).
             */
            setX: function(el, x) {
                Y.Dom.setXY(el, [x, null]);
            },

            /**
             * Set the Y position of an html element in page coordinates, regardless of how the element is positioned.
             * The element must be part of the DOM tree to have page coordinates (display:none or elements not appended return false).
             * @method setY
             * @param {String | HTMLElement | Array} el Accepts a string to use as an ID, an actual DOM reference, or an Array of IDs and/or HTMLElements.
             * @param {Int} x To use as the Y coordinate for the element(s).
             */
            setY: function(el, y) {
                Y.Dom.setXY(el, [null, y]);
            },

            /**
             * Returns the region position of the given element.
             * The element must be part of the DOM tree to have a region (display:none or elements not appended return false).
             * @method getRegion
             * @param {String | HTMLElement | Array} el Accepts a string to use as an ID, an actual DOM reference, or an Array of IDs and/or HTMLElements.
             * @return {Region | Array} A Region or array of Region instances containing "top, left, bottom, right" member data.
             */
            getRegion: function(el) {
                var f = function(el) {
                    var region = new Y.Region.getRegion(el);
                    return region;
                };

                return Y.Dom.batch(el, f, Y.Dom, true);
            },

            /**
             * Returns the width of the client (viewport).
             * @method getClientWidth
             * @deprecated Now using getViewportWidth.  This interface left intact for back compat.
             * @return {Int} The width of the viewable area of the page.
             */
            getClientWidth: function() {
                return Y.Dom.getViewportWidth();
            },

            /**
             * Returns the height of the client (viewport).
             * @method getClientHeight
             * @deprecated Now using getViewportHeight.  This interface left intact for back compat.
             * @return {Int} The height of the viewable area of the page.
             */
            getClientHeight: function() {
                return Y.Dom.getViewportHeight();
            },

            /**
             * Returns a array of HTMLElements with the given class.
             * For optimized performance, include a tag and/or root node when possible.
             * @method getElementsByClassName
             * @param {String} className The class name to match against
             * @param {String} tag (optional) The tag name of the elements being collected
             * @param {String | HTMLElement} root (optional) The HTMLElement or an ID to use as the starting point
             * @return {Array} An array of elements that have the given class name
             */
            getElementsByClassName: function(className, tag, root) {
                var method = function(el) { return Y.Dom.hasClass(el, className); };
                return Y.Dom.getElementsBy(method, tag, root);
            },

            /**
             * Determines whether an HTMLElement has the given className.
             * @method hasClass
             * @param {String | HTMLElement | Array} el The element or collection to test
             * @param {String} className the class name to search for
             * @return {Boolean | Array} A boolean value or array of boolean values
             */
            hasClass: function(el, className) {
                var re = new RegExp('(?:^|\\s+)' + className + '(?:\\s+|$)');

                var f = function(el) {
                    return re.test(el['className']);
                };

                return Y.Dom.batch(el, f, Y.Dom, true);
            },

            /**
             * Adds a class name to a given element or collection of elements.
             * @method addClass
             * @param {String | HTMLElement | Array} el The element or collection to add the class to
             * @param {String} className the class name to add to the class attribute
             */
            addClass: function(el, className) {
                var f = function(el) {
                    if (this.hasClass(el, className)) { return; } // already present

                    el['className'] = [el['className'], className].join(' ');
                };

                Y.Dom.batch(el, f, Y.Dom, true);
            },

            /**
             * Removes a class name from a given element or collection of elements.
             * @method removeClass
             * @param {String | HTMLElement | Array} el The element or collection to remove the class from
             * @param {String} className the class name to remove from the class attribute
             */
            removeClass: function(el, className) {
                var re = new RegExp('(?:^|\\s+)' + className + '(?:\\s+|$)', 'g');

                var f = function(el) {
                    if (!this.hasClass(el, className)) { return; } // not present

                    var c = el['className'];
                    el['className'] = c.replace(re, ' ');
                    if ( this.hasClass(el, className) ) { // in case of multiple adjacent
                        this.removeClass(el, className);
                    }

                };

                Y.Dom.batch(el, f, Y.Dom, true);
            },

            /**
             * Replace a class with another class for a given element or collection of elements.
             * If no oldClassName is present, the newClassName is simply added.
             * @method replaceClass
             * @param {String | HTMLElement | Array} el The element or collection to remove the class from
             * @param {String} oldClassName the class name to be replaced
             * @param {String} newClassName the class name that will be replacing the old class name
             */
            replaceClass: function(el, oldClassName, newClassName) {
                if (oldClassName === newClassName) { // avoid infinite loop
                    return false;
                }

                var re = new RegExp('(?:^|\\s+)' + oldClassName + '(?:\\s+|$)', 'g');

                var f = function(el) {

                    if ( !this.hasClass(el, oldClassName) ) {
                        this.addClass(el, newClassName); // just add it if nothing to replace
                        return; // note return
                    }

                    el['className'] = el['className'].replace(re, ' ' + newClassName + ' ');

                    if ( this.hasClass(el, oldClassName) ) { // in case of multiple adjacent
                        this.replaceClass(el, oldClassName, newClassName);
                    }
                };

                Y.Dom.batch(el, f, Y.Dom, true);
            },

            /**
             * Generates a unique ID
             * @method generateId
             * @param {String | HTMLElement | Array} el (optional) An optional element array of elements to add an ID to (no ID is added if one is already present).
             * @param {String} prefix (optional) an optional prefix to use (defaults to "yui-gen").
             * @return {String | Array} The generated ID, or array of generated IDs (or original ID if already present on an element)
             */
            generateId: function(el, prefix) {
                prefix = prefix || 'yui-gen';
                el = el || {};

                var f = function(el) {
                    if (el) {
                        el = Y.Dom.get(el);
                    } else {
                        el = {}; // just generating ID in this case
                    }

                    if (!el.id) {
                        el.id = prefix + id_counter++;
                    } // dont override existing

                    return el.id;
                };

                return Y.Dom.batch(el, f, Y.Dom, true);
            },

            /**
             * Determines whether an HTMLElement is an ancestor of another HTML element in the DOM hierarchy.
             * @method isAncestor
             * @param {String | HTMLElement} haystack The possible ancestor
             * @param {String | HTMLElement} needle The possible descendent
             * @return {Boolean} Whether or not the haystack is an ancestor of needle
             */
            isAncestor: function(haystack, needle) {
                haystack = Y.Dom.get(haystack);
                if (!haystack || !needle) { return false; }

                var f = function(needle) {
                    if (haystack.contains && !isSafari) { // safari "contains" is broken
                        return haystack.contains(needle);
                    }
                    else if ( haystack.compareDocumentPosition ) {
                        return !!(haystack.compareDocumentPosition(needle) & 16);
                    }
                    else { // loop up and test each parent
                        var parent = needle.parentNode;

                        while (parent) {
                            if (parent == haystack) {
                                return true;
                            }
                            else if (!parent.tagName || parent.tagName.toUpperCase() == 'HTML') {
                                return false;
                            }

                            parent = parent.parentNode;
                        }
                        return false;
                    }
                };

                return Y.Dom.batch(needle, f, Y.Dom, true);
            },

            /**
             * Determines whether an HTMLElement is present in the current document.
             * @method inDocument
             * @param {String | HTMLElement} el The element to search for
             * @return {Boolean} Whether or not the element is present in the current document
             */
            inDocument: function(el) {
                var f = function(el) {
                    return this.isAncestor(document.documentElement, el);
                };

                return Y.Dom.batch(el, f, Y.Dom, true);
            },

            /**
             * Returns a array of HTMLElements that pass the test applied by supplied boolean method.
             * For optimized performance, include a tag and/or root node when possible.
             * @method getElementsBy
             * @param {Function} method - A boolean method for testing elements which receives the element as its only argument.

             * @param {String} tag (optional) The tag name of the elements being collected
             * @param {String | HTMLElement} root (optional) The HTMLElement or an ID to use as the starting point
             */
            getElementsBy: function(method, tag, root) {
                tag = tag || '*';
                root = Y.Dom.get(root) || document;

                var nodes = [];
                var elements = root.getElementsByTagName(tag);

                if ( !elements.length && (tag == '*' && root.all) ) {
                    elements = root.all; // IE < 6
                }

                for (var i = 0, len = elements.length; i < len; ++i) {
                    if ( method(elements[i]) ) { nodes[nodes.length] = elements[i]; }
                }

                return nodes;
            },

            /**
             * Returns an array of elements that have had the supplied method applied.
             * The method is called with the element(s) as the first arg, and the optional param as the second ( method(el, o) ).
             * @method batch
             * @param {String | HTMLElement | Array} el (optional) An element or array of elements to apply the method to
             * @param {Function} method The method to apply to the element(s)
             * @param {Any} o (optional) An optional arg that is passed to the supplied method
             * @param {Boolean} override (optional) Whether or not to override the scope of "method" with "o"
             * @return {HTMLElement | Array} The element(s) with the method applied
             */
            batch: function(el, method, o, override) {
                var id = el;
                el = Y.Dom.get(el);

                var scope = (override) ? o : window;

                if (!el || el.tagName || !el.length) { // is null or not a collection (tagName for SELECT and others that can be both an element and a collection)
                    if (!el) {
                        return false;
                    }
                    return method.call(scope, el, o);
                }

                var collection = [];

                for (var i = 0, len = el.length; i < len; ++i) {
                    if (!el[i]) {
                        id = el[i];
                    }
                    collection[collection.length] = method.call(scope, el[i], o);
                }

                return collection;
            },

            /**
             * Returns the height of the document.
             * @method getDocumentHeight
             * @return {Int} The height of the actual document (which includes the body and its margin).
             */
            getDocumentHeight: function() {
                var scrollHeight = (document.compatMode != 'CSS1Compat') ? document.body.scrollHeight : document.documentElement.scrollHeight;

                var h = Math.max(scrollHeight, Y.Dom.getViewportHeight());
                return h;
            },

            /**
             * Returns the width of the document.
             * @method getDocumentWidth
             * @return {Int} The width of the actual document (which includes the body and its margin).
             */
            getDocumentWidth: function() {
                var scrollWidth = (document.compatMode != 'CSS1Compat') ? document.body.scrollWidth : document.documentElement.scrollWidth;
                var w = Math.max(scrollWidth, Y.Dom.getViewportWidth());
                return w;
            },

            /**
             * Returns the current height of the viewport.
             * @method getViewportHeight
             * @return {Int} The height of the viewable area of the page (excludes scrollbars).
             */
            getViewportHeight: function() {
                var height = self.innerHeight; // Safari, Opera
                var mode = document.compatMode;

                if ( (mode || isIE) && !isOpera ) { // IE, Gecko
                    height = (mode == 'CSS1Compat') ?
                            document.documentElement.clientHeight : // Standards
                            document.body.clientHeight; // Quirks
                }

                return height;
            },

            /**
             * Returns the current width of the viewport.
             * @method getViewportWidth
             * @return {Int} The width of the viewable area of the page (excludes scrollbars).
             */

            getViewportWidth: function() {
                var width = self.innerWidth;  // Safari
                var mode = document.compatMode;

                if (mode || isIE) { // IE, Gecko, Opera
                    width = (mode == 'CSS1Compat') ?
                            document.documentElement.clientWidth : // Standards
                            document.body.clientWidth; // Quirks
                }
                return width;
            }
        };
    })();
    /**
     * A region is a representation of an object on a grid.  It is defined
     * by the top, right, bottom, left extents, so is rectangular by default.  If
     * other shapes are required, this class could be extended to support it.
     * @namespace YAHOO.util
     * @class Region
     * @param {Int} t the top extent
     * @param {Int} r the right extent
     * @param {Int} b the bottom extent
     * @param {Int} l the left extent
     * @constructor
     */
    YAHOO.util.Region = function(t, r, b, l) {

        /**
         * The region's top extent
         * @property top
         * @type Int
         */
        this.top = t;

        /**
         * The region's top extent as index, for symmetry with set/getXY
         * @property 1
         * @type Int
         */
        this[1] = t;

        /**
         * The region's right extent
         * @property right
         * @type int
         */
        this.right = r;

        /**
         * The region's bottom extent
         * @property bottom
         * @type Int
         */
        this.bottom = b;

        /**
         * The region's left extent
         * @property left
         * @type Int
         */
        this.left = l;

        /**
         * The region's left extent as index, for symmetry with set/getXY
         * @property 0
         * @type Int
         */
        this[0] = l;
    };

    /**
     * Returns true if this region contains the region passed in
     * @method contains
     * @param  {Region}  region The region to evaluate
     * @return {Boolean}        True if the region is contained with this region,
     *                          else false
     */
    YAHOO.util.Region.prototype.contains = function(region) {
        return ( region.left   >= this.left   &&
                 region.right  <= this.right  &&
                 region.top    >= this.top    &&
                 region.bottom <= this.bottom    );

    };

    /**
     * Returns the area of the region
     * @method getArea
     * @return {Int} the region's area
     */
    YAHOO.util.Region.prototype.getArea = function() {
        return ( (this.bottom - this.top) * (this.right - this.left) );
    };

    /**
     * Returns the region where the passed in region overlaps with this one
     * @method intersect
     * @param  {Region} region The region that intersects
     * @return {Region}        The overlap region, or null if there is no overlap
     */
    YAHOO.util.Region.prototype.intersect = function(region) {
        var t = Math.max( this.top,    region.top    );
        var r = Math.min( this.right,  region.right  );
        var b = Math.min( this.bottom, region.bottom );
        var l = Math.max( this.left,   region.left   );

        if (b >= t && r >= l) {
            return new YAHOO.util.Region(t, r, b, l);
        } else {
            return null;
        }
    };

    /**
     * Returns the region representing the smallest region that can contain both
     * the passed in region and this region.
     * @method union
     * @param  {Region} region The region that to create the union with
     * @return {Region}        The union region
     */
    YAHOO.util.Region.prototype.union = function(region) {
        var t = Math.min( this.top,    region.top    );
        var r = Math.max( this.right,  region.right  );
        var b = Math.max( this.bottom, region.bottom );
        var l = Math.min( this.left,   region.left   );

        return new YAHOO.util.Region(t, r, b, l);
    };

    /**
     * toString
     * @method toString
     * @return string the region properties
     */
    YAHOO.util.Region.prototype.toString = function() {
        return ( "Region {"    +
                 "top: "       + this.top    +
                 ", right: "   + this.right  +
                 ", bottom: "  + this.bottom +
                 ", left: "    + this.left   +
                 "}" );
    };

    /**
     * Returns a region that is occupied by the DOM element
     * @method getRegion
     * @param  {HTMLElement} el The element
     * @return {Region}         The region that the element occupies
     * @static
     */
    YAHOO.util.Region.getRegion = function(el) {
        var p = YAHOO.util.Dom.getXY(el);

        var t = p[1];
        var r = p[0] + el.offsetWidth;
        var b = p[1] + el.offsetHeight;
        var l = p[0];

        return new YAHOO.util.Region(t, r, b, l);
    };

    /////////////////////////////////////////////////////////////////////////////

    /**
     * A point is a region that is special in that it represents a single point on
     * the grid.
     * @namespace YAHOO.util
     * @class Point
     * @param {Int} x The X position of the point
     * @param {Int} y The Y position of the point
     * @constructor
     * @extends YAHOO.util.Region
     */
    YAHOO.util.Point = function(x, y) {
       if (x instanceof Array) { // accept output from Dom.getXY
          y = x[1];
          x = x[0];
       }

        /**
         * The X position of the point, which is also the right, left and index zero (for Dom.getXY symmetry)
         * @property x
         * @type Int
         */

        this.x = this.right = this.left = this[0] = x;

        /**
         * The Y position of the point, which is also the top, bottom and index one (for Dom.getXY symmetry)
         * @property y
         * @type Int
         */
        this.y = this.top = this.bottom = this[1] = y;
    };

    YAHOO.util.Point.prototype = new YAHOO.util.Region();

yui-ext - Copyright © 2006 Jack Slocum. | Yahoo! UI - Copyright © 2006 Yahoo! Inc.
All rights reserved.