/**
 * @class Ext.Element
 */
Ext.Element.addMethods({
    
/**
     * Looks at this node and then at parent nodes for a match of the passed simple selector (e.g. div.some-class or span:first-child)
     * @param {String} selector The simple selector to test
     * @param {Number/Mixed} maxDepth (optional) The max depth to search as a number or element (defaults to 50 || document.body)
     * @param {Boolean} returnEl (optional) True to return a Ext.Element object instead of DOM node
     * @return {HTMLElement} The matching DOM node (or null if no match was found)
     */
    findParent : function(simpleSelector, maxDepth, returnEl) {
        var p = this.dom,
            b = document.body,
            depth = 0,
            stopEl;

        maxDepth = maxDepth || 50;
        if (isNaN(maxDepth)) {
            stopEl = Ext.getDom(maxDepth);
            maxDepth = Number.MAX_VALUE;
        }
        while (p && p.nodeType == 1 && depth < maxDepth && p != b && p != stopEl) {
            if (Ext.DomQuery.is(p, simpleSelector)) {
                return returnEl ? Ext.get(p) : p;
            }
            depth++;
            p = p.parentNode;
        }
        return null;
    },
    
    
/**
     * Looks at parent nodes for a match of the passed simple selector (e.g. div.some-class or span:first-child)
     * @param {String} selector The simple selector to test
     * @param {Number/Mixed} maxDepth (optional) The max depth to
            search as a number or element (defaults to 10 || document.body)
     * @param {Boolean} returnEl (optional) True to return a Ext.Element object instead of DOM node
     * @return {HTMLElement} The matching DOM node (or null if no match was found)
     */
    findParentNode : function(simpleSelector, maxDepth, returnEl) {
        var p = Ext.fly(this.dom.parentNode, '_internal');
        return p ? p.findParent(simpleSelector, maxDepth, returnEl) : null;
    },

    
/**
     * Walks up the dom looking for a parent node that matches the passed simple selector (e.g. div.some-class or span:first-child).
     * This is a shortcut for findParentNode() that always returns an Ext.Element.
     * @param {String} selector The simple selector to test
     * @param {Number/Mixed} maxDepth (optional) The max depth to
            search as a number or element (defaults to 10 || document.body)
     * @return {Ext.Element} The matching DOM node (or null if no match was found)
     */
    up : function(simpleSelector, maxDepth) {
        return this.findParentNode(simpleSelector, maxDepth, true);
    },

    
/**
     * Creates a {@link Ext.CompositeElement} for child nodes based on the passed CSS selector (the selector should not contain an id).
     * @param {String} selector The CSS selector
     * @return {CompositeElement/CompositeElement} The composite element
     */
    select : function(selector, composite) {
        return Ext.Element.select(selector, this.dom, composite);
    },

    
/**
     * Selects child nodes based on the passed CSS selector (the selector should not contain an id).
     * @param {String} selector The CSS selector
     * @return {Array} An array of the matched nodes
     */
    query : function(selector) {
        return Ext.DomQuery.select(selector, this.dom);
    },

    
/**
     * Selects a single child at any depth below this element based on the passed CSS selector (the selector should not contain an id).
     * @param {String} selector The CSS selector
     * @param {Boolean} returnDom (optional) True to return the DOM node instead of Ext.Element (defaults to false)
     * @return {HTMLElement/Ext.Element} The child Ext.Element (or DOM node if returnDom = true)
     */
    down : function(selector, returnDom) {
        var n = Ext.DomQuery.selectNode(selector, this.dom);
        return returnDom ? n : Ext.get(n);
    },

    
/**
     * Selects a single *direct* child based on the passed CSS selector (the selector should not contain an id).
     * @param {String} selector The CSS selector
     * @param {Boolean} returnDom (optional) True to return the DOM node instead of Ext.Element (defaults to false)
     * @return {HTMLElement/Ext.Element} The child Ext.Element (or DOM node if returnDom = true)
     */
    child : function(selector, returnDom) {
        var node,
            me = this,
            id;
        id = Ext.get(me).id;
        // Escape . or :
        id = id.replace(/[\.:]/g, "\\$0");
        node = Ext.DomQuery.selectNode('#' + id + " > " + selector, me.dom);
        return returnDom ? node : Ext.get(node);
    },

     
/**
     * Gets the parent node for this element, optionally chaining up trying to match a selector
     * @param {String} selector (optional) Find a parent node that matches the passed simple selector
     * @param {Boolean} returnDom (optional) True to return a raw dom node instead of an Ext.Element
     * @return {Ext.Element/HTMLElement} The parent node or null
     */
    parent : function(selector, returnDom) {
        return this.matchNode('parentNode', 'parentNode', selector, returnDom);
    },

     
/**
     * Gets the next sibling, skipping text nodes
     * @param {String} selector (optional) Find the next sibling that matches the passed simple selector
     * @param {Boolean} returnDom (optional) True to return a raw dom node instead of an Ext.Element
     * @return {Ext.Element/HTMLElement} The next sibling or null
     */
    next : function(selector, returnDom) {
        return this.matchNode('nextSibling', 'nextSibling', selector, returnDom);
    },

    
/**
     * Gets the previous sibling, skipping text nodes
     * @param {String} selector (optional) Find the previous sibling that matches the passed simple selector
     * @param {Boolean} returnDom (optional) True to return a raw dom node instead of an Ext.Element
     * @return {Ext.Element/HTMLElement} The previous sibling or null
     */
    prev : function(selector, returnDom) {
        return this.matchNode('previousSibling', 'previousSibling', selector, returnDom);
    },


    
/**
     * Gets the first child, skipping text nodes
     * @param {String} selector (optional) Find the next sibling that matches the passed simple selector
     * @param {Boolean} returnDom (optional) True to return a raw dom node instead of an Ext.Element
     * @return {Ext.Element/HTMLElement} The first child or null
     */
    first : function(selector, returnDom) {
        return this.matchNode('nextSibling', 'firstChild', selector, returnDom);
    },

    
/**
     * Gets the last child, skipping text nodes
     * @param {String} selector (optional) Find the previous sibling that matches the passed simple selector
     * @param {Boolean} returnDom (optional) True to return a raw dom node instead of an Ext.Element
     * @return {Ext.Element/HTMLElement} The last child or null
     */
    last : function(selector, returnDom) {
        return this.matchNode('previousSibling', 'lastChild', selector, returnDom);
    },

    matchNode : function(dir, start, selector, returnDom) {
        if (!this.dom)
            return null;
        
        var n = this.dom[start];
        while (n) {
            if (n.nodeType == 1 && (!selector || Ext.DomQuery.is(n, selector))) {
                return !returnDom ? Ext.get(n) : n;
            }
            n = n[dir];
        }
        return null;
    }
});