/**
 * @class Ext.Template
 * Represents an HTML fragment template. Templates can be precompiled for greater performance.
 * For a list of available format functions, see {@link Ext.util.Format}.

 * Usage:

var t = new Ext.Template(
    '<div name="{id}">',
        '<span class="{cls}">{name:trim} {value:ellipsis(10)}</span>',
    '</div>'
);
t.append('some-element', {id: 'myid', cls: 'myclass', name: 'foo', value: 'bar'});

 * @constructor
 * @param {String/Array} html The HTML fragment or an array of fragments to join("") or multiple arguments to join("")
 */
Ext.Template = function(html){
    var me = this,
    	a = arguments,
    	buf = [];

    if (Ext.isArray(html)) {
        html = html.join("");
    } else if (a.length > 1) {
	    Ext.each(a, function(v) {
            if (Ext.isObject(v)) {
                Ext.apply(me, v);
            } else {
                buf.push(v);
            }
        });
        html = buf.join('');
    }

    /**@private*/
    me.html = html;
    if (me.compiled) {
        me.compile();
    }
};
Ext.Template.prototype = {
    
/**
     * Returns an HTML fragment of this template with the specified values applied.
     * @param {Object/Array} values The template values. Can be an array if your params are numeric (i.e. {0}) or an object (i.e. {foo: 'bar'})
     * @return {String} The HTML fragment
     */
    applyTemplate : function(values){
		var me = this;

        return me.compiled ?
        		me.compiled(values) :
				me.html.replace(me.re, function(m, name){
		        	return values[name] !== undefined ? values[name] : "";
		        });
	},

    
/**
     * Sets the HTML used as the template and optionally compiles it.
     * @param {String} html
     * @param {Boolean} compile (optional) True to compile the template (defaults to undefined)
     * @return {Ext.Template} this
     */
    set : function(html, compile){
	    var me = this;
        me.html = html;
        me.compiled = null;
        return compile ? me.compile() : me;
    },

    
/**
    * The regular expression used to match template variables
    * @type RegExp
    * @property
    */
    re : /\{([\w-]+)\}/g,

    
/**
     * Compiles the template into an internal function, eliminating the RegEx overhead.
     * @return {Ext.Template} this
     */
    compile : function(){
        var me = this,
        	sep = Ext.isGecko ? "+" : ",";

        function fn(m, name){                        
	        name = "values['" + name + "']";
	        return "'"+ sep + '(' + name + " == undefined ? '' : " + name + ')' + sep + "'";
        }
                
        eval("this.compiled = function(values){ return " + (Ext.isGecko ? "'" : "['") +
             me.html.replace(/\\/g, '\\\\').replace(/(\r\n|\n)/g, '\\n').replace(/'/g, "\\'").replace(this.re, fn) +
             (Ext.isGecko ?  "';};" : "'].join('');};"));
        return me;
    },

    
/**
     * Applies the supplied values to the template and inserts the new node(s) as the first child of el.
     * @param {Mixed} el The context element
     * @param {Object/Array} values The template values. Can be an array if your params are numeric (i.e. {0}) or an object (i.e. {foo: 'bar'})
     * @param {Boolean} returnElement (optional) true to return a Ext.Element (defaults to undefined)
     * @return {HTMLElement/Ext.Element} The new node or Element
     */
    insertFirst: function(el, values, returnElement){
        return this.doInsert('afterBegin', el, values, returnElement);
    },

    
/**
     * Applies the supplied values to the template and inserts the new node(s) before el.
     * @param {Mixed} el The context element
     * @param {Object/Array} values The template values. Can be an array if your params are numeric (i.e. {0}) or an object (i.e. {foo: 'bar'})
     * @param {Boolean} returnElement (optional) true to return a Ext.Element (defaults to undefined)
     * @return {HTMLElement/Ext.Element} The new node or Element
     */
    insertBefore: function(el, values, returnElement){
        return this.doInsert('beforeBegin', el, values, returnElement);
    },

    
/**
     * Applies the supplied values to the template and inserts the new node(s) after el.
     * @param {Mixed} el The context element
     * @param {Object/Array} values The template values. Can be an array if your params are numeric (i.e. {0}) or an object (i.e. {foo: 'bar'})
     * @param {Boolean} returnElement (optional) true to return a Ext.Element (defaults to undefined)
     * @return {HTMLElement/Ext.Element} The new node or Element
     */
    insertAfter : function(el, values, returnElement){
        return this.doInsert('afterEnd', el, values, returnElement);
    },

    
/**
     * Applies the supplied values to the template and appends the new node(s) to el.
     * @param {Mixed} el The context element
     * @param {Object/Array} values The template values. Can be an array if your params are numeric (i.e. {0}) or an object (i.e. {foo: 'bar'})
     * @param {Boolean} returnElement (optional) true to return a Ext.Element (defaults to undefined)
     * @return {HTMLElement/Ext.Element} The new node or Element
     */
    append : function(el, values, returnElement){
        return this.doInsert('beforeEnd', el, values, returnElement);
    },

    doInsert : function(where, el, values, returnEl){
        el = Ext.getDom(el);
        var newNode = Ext.DomHelper.insertHtml(where, el, this.applyTemplate(values));
        return returnEl ? Ext.get(newNode, true) : newNode;
    },

    
/**
     * Applies the supplied values to the template and overwrites the content of el with the new node(s).
     * @param {Mixed} el The context element
     * @param {Object/Array} values The template values. Can be an array if your params are numeric (i.e. {0}) or an object (i.e. {foo: 'bar'})
     * @param {Boolean} returnElement (optional) true to return a Ext.Element (defaults to undefined)
     * @return {HTMLElement/Ext.Element} The new node or Element
     */
    overwrite : function(el, values, returnElement){
        el = Ext.getDom(el);
        el.innerHTML = this.applyTemplate(values);
        return returnElement ? Ext.get(el.firstChild, true) : el.firstChild;
    }
};
/**
 * Alias for {@link #applyTemplate}
 * Returns an HTML fragment of this template with the specified values applied.
 * @param {Object/Array} values The template values. Can be an array if your params are numeric (i.e. {0}) or an object (i.e. {foo: 'bar'})
 * @return {String} The HTML fragment
 * @member Ext.Template
 * @method apply
 */
Ext.Template.prototype.apply = Ext.Template.prototype.applyTemplate;

/**
 * Creates a template from the passed element's value (display:none textarea, preferred) or innerHTML.
 * @param {String/HTMLElement} el A DOM element or its id
 * @param {Object} config A configuration object
 * @return {Ext.Template} The created template
 * @static
 */
Ext.Template.from = function(el, config){
    el = Ext.getDom(el);
    return new Ext.Template(el.value || el.innerHTML, config || '');
};