ejs.js

(function(){
    

var rsplit = function(string, regex) {
	var result = regex.exec(string),retArr = new Array(), first_idx, last_idx, first_bit;
	while (result != null)
	{
		first_idx = result.index; last_idx = regex.lastIndex;
		if ((first_idx) != 0)
		{
			first_bit = string.substring(0,first_idx);
			retArr.push(string.substring(0,first_idx));
			string = string.slice(first_idx);
		}		
		retArr.push(result[0]);
		string = string.slice(result[0].length);
		result = regex.exec(string);	
	}
	if (! string == '')
	{
		retArr.push(string);
	}
	return retArr;
},
chop =  function(string){
    return string.substr(0, string.length - 1);
},
extend = function(d, s){
    for(var n in s){
        if(s.hasOwnProperty(n))  d[n] = s[n]
    }
}


EJS = function( options ){
	options = typeof options == "string" ? {view: options} : options
    this.set_options(options);
	if(options.precompiled){
		this.template = {};
		this.template.process = options.precompiled;
		EJS.update(this.name, this);
		return;
	}
    if(options.element)
	{
		if(typeof options.element == 'string'){
			var name = options.element
			options.element = document.getElementById(  options.element )
			if(options.element == null) throw name+'does not exist!'
		}
		if(options.element.value){
			this.text = options.element.value
		}else{
			this.text = options.element.innerHTML
		}
		this.name = options.element.id
		this.type = '['
	}else if(options.url){
        options.url = EJS.endExt(options.url, this.extMatch);
		this.name = this.name ? this.name : options.url;
        var url = options.url
        //options.view = options.absolute_url || options.view || options.;
		var template = EJS.get(this.name /*url*/, this.cache);
		if (template) return template;
	    if (template == EJS.INVALID_PATH) return null;
        try{
            this.text = EJS.request( url+(this.cache ? '' : '?'+Math.random() ));
        }catch(e){}

		if(this.text == null){
            throw( {type: 'EJS', message: 'There is no template at '+url}  );
		}
		//this.name = url;
	}
	var template = new EJS.Compiler(this.text, this.type);

	template.compile(options, this.name);

	
	EJS.update(this.name, this);
	this.template = template;
};
/* @Prototype*/
EJS.prototype = {
	/**
	 * Renders an object with extra view helpers attached to the view.
	 * @param {Object} object data to be rendered
	 * @param {Object} extra_helpers an object with additonal view helpers
	 * @return {String} returns the result of the string
	 */
    render : function(object, extra_helpers){
        object = object || {};
        this._extra_helpers = extra_helpers;
		var v = new EJS.Helpers(object, extra_helpers || {});
		return this.template.process.call(object, object,v);
	},
    update : function(element, options){
        if(typeof element == 'string'){
			element = document.getElementById(element)
		}
		if(options == null){
			_template = this;
			return function(object){
				EJS.prototype.update.call(_template, element, object)
			}
		}
		if(typeof options == 'string'){
			params = {}
			params.url = options
			_template = this;
			params.onComplete = function(request){
				var object = eval( request.responseText )
				EJS.prototype.update.call(_template, element, object)
			}
			EJS.ajax_request(params)
		}else
		{
			element.innerHTML = this.render(options)
		}
    },
	out : function(){
		return this.template.out;
	},
    /**
     * Sets options on this view to be rendered with.
     * @param {Object} options
     */
	set_options : function(options){
        this.type = options.type || EJS.type;
		this.cache = options.cache != null ? options.cache : EJS.cache;
		this.text = options.text || null;
		this.name =  options.name || null;
		this.ext = options.ext || EJS.ext;
		this.extMatch = new RegExp(this.ext.replace(/\./, '\.'));
	}
};
EJS.endExt = function(path, match){
	if(!path) return null;
	match.lastIndex = 0
	return path+ (match.test(path) ? '' : this.ext )
}




/* @Static*/
EJS.Scanner = function(source, left, right) {
	
    extend(this,
        {left_delimiter: 	left +'%',
         right_delimiter: 	'%'+right,
         double_left: 		left+'%%',
         double_right:  	'%%'+right,
         left_equal: 		left+'%=',
         left_comment: 	left+'%#'})

	this.SplitRegexp = left=='[' ? /(\[%%)|(%%\])|(\[%=)|(\[%#)|(\[%)|(%\]\n)|(%\])|(\n)/ : new RegExp('('+this.double_left+')|(%%'+this.double_right+')|('+this.left_equal+')|('+this.left_comment+')|('+this.left_delimiter+')|('+this.right_delimiter+'\n)|('+this.right_delimiter+')|(\n)') ;
	
	this.source = source;
	this.stag = null;
	this.lines = 0;
};

EJS.Scanner.to_text = function(input){
	if(input == null || input === undefined)
        return '';
    if(input instanceof Date)
		return input.toDateString();
	if(input.toString) 
        return input.toString();
	return '';
};

EJS.Scanner.prototype = {
  scan: function(block) {
     scanline = this.scanline;
	 regex = this.SplitRegexp;
	 if (! this.source == '')
	 {
	 	 var source_split = rsplit(this.source, /\n/);
	 	 for(var i=0; i<source_split.length; i++) {
		 	 var item = source_split[i];
			 this.scanline(item, regex, block);
		 }
	 }
  },
  scanline: function(line, regex, block) {
	 this.lines++;
	 var line_split = rsplit(line, regex);
 	 for(var i=0; i<line_split.length; i++) {
	   var token = line_split[i];
       if (token != null) {
		   	try{
	         	block(token, this);
		 	}catch(e){
				throw {type: 'EJS.Scanner', line: this.lines};
			}
       }
	 }
  }
};


EJS.Buffer = function(pre_cmd, post_cmd) {
	this.line = new Array();
	this.script = "";
	this.pre_cmd = pre_cmd;
	this.post_cmd = post_cmd;
	for (var i=0; i<this.pre_cmd.length; i++)
	{
		this.push(pre_cmd[i]);
	}
};
EJS.Buffer.prototype = {
	
  push: function(cmd) {
	this.line.push(cmd);
  },

  cr: function() {
	this.script = this.script + this.line.join('; ');
	this.line = new Array();
	this.script = this.script + "\n";
  },

  close: function() {
	if (this.line.length > 0)
	{
		for (var i=0; i<this.post_cmd.length; i++){
			this.push(pre_cmd[i]);
		}
		this.script = this.script + this.line.join('; ');
		line = null;
	}
  }
 	
};


EJS.Compiler = function(source, left) {
    this.pre_cmd = ['var ___ViewO = [];'];
	this.post_cmd = new Array();
	this.source = ' ';	
	if (source != null)
	{
		if (typeof source == 'string')
		{
		    source = source.replace(/\r\n/g, "\n");
            source = source.replace(/\r/g,   "\n");
			this.source = source;
		}else if (source.innerHTML){
			this.source = source.innerHTML;
		} 
		if (typeof this.source != 'string'){
			this.source = "";
		}
	}
	left = left || '<';
	var right = '>';
	switch(left) {
		case '[':
			right = ']';
			break;
		case '<':
			break;
		default:
			throw left+' is not a supported deliminator';
			break;
	}
	this.scanner = new EJS.Scanner(this.source, left, right);
	this.out = '';
};
EJS.Compiler.prototype = {
  compile: function(options, name) {
  	options = options || {};
	this.out = '';
	var put_cmd = "___ViewO.push(";
	var insert_cmd = put_cmd;
	var buff = new EJS.Buffer(this.pre_cmd, this.post_cmd);		
	var content = '';
	var clean = function(content)
	{
	    content = content.replace(/\\/g, '\\\\');
        content = content.replace(/\n/g, '\\n');
        content = content.replace(/"/g,  '\\"');
        return content;
	};
	this.scanner.scan(function(token, scanner) {
		if (scanner.stag == null)
		{
			switch(token) {
				case '\n':
					content = content + "\n";
					buff.push(put_cmd + '"' + clean(content) + '");');
					buff.cr();
					content = '';
					break;
				case scanner.left_delimiter:
				case scanner.left_equal:
				case scanner.left_comment:
					scanner.stag = token;
					if (content.length > 0)
					{
						buff.push(put_cmd + '"' + clean(content) + '")');
					}
					content = '';
					break;
				case scanner.double_left:
					content = content + scanner.left_delimiter;
					break;
				default:
					content = content + token;
					break;
			}
		}
		else {
			switch(token) {
				case scanner.right_delimiter:
					switch(scanner.stag) {
						case scanner.left_delimiter:
							if (content[content.length - 1] == '\n')
							{
								content = chop(content);
								buff.push(content);
								buff.cr();
							}
							else {
								buff.push(content);
							}
							break;
						case scanner.left_equal:
							buff.push(insert_cmd + "(EJS.Scanner.to_text(" + content + ")))");
							break;
					}
					scanner.stag = null;
					content = '';
					break;
				case scanner.double_right:
					content = content + scanner.right_delimiter;
					break;
				default:
					content = content + token;
					break;
			}
		}
	});
	if (content.length > 0)
	{
		// Chould be content.dump in Ruby
		buff.push(put_cmd + '"' + clean(content) + '")');
	}
	buff.close();
	this.out = buff.script + ";";
	var to_be_evaled = '/*'+name+'*/this.process = function(_CONTEXT,_VIEW) { try { with(_VIEW) { with (_CONTEXT) {'+this.out+" return ___ViewO.join('');}}}catch(e){e.lineNumber=null;throw e;}};";
	
	try{
		eval(to_be_evaled);
	}catch(e){
		if(typeof JSLINT != 'undefined'){
			JSLINT(this.out);
			for(var i = 0; i < JSLINT.errors.length; i++){
				var error = JSLINT.errors[i];
				if(error.reason != "Unnecessary semicolon."){
					error.line++;
					var e = new Error();
					e.lineNumber = error.line;
					e.message = error.reason;
					if(options.view)
						e.fileName = options.view;
					throw e;
				}
			}
		}else{
			throw e;
		}
	}
  }
};


//type, cache, folder
/**
 * Sets default options for all views
 * @param {Object} options Set view with the following options
 * <table class="options">
				<tbody><tr><th>Option</th><th>Default</th><th>Description</th></tr>
				<tr>
					<td>type</td>
					<td>'<'</td>
					<td>type of magic tags.  Options are '&lt;' or '['
					</td>
				</tr>
				<tr>
					<td>cache</td>
					<td>true in production mode, false in other modes</td>
					<td>true to cache template.
					</td>
				</tr>
	</tbody></table>
 * 
 */
EJS.config = function(options){
	EJS.cache = options.cache != null ? options.cache : EJS.cache;
	EJS.type = options.type != null ? options.type : EJS.type;
	EJS.ext = options.ext != null ? options.ext : EJS.ext;
	
	var templates_directory = EJS.templates_directory || {}; //nice and private container
	EJS.templates_directory = templates_directory;
	EJS.get = function(path, cache){
		if(cache == false) return null;
		if(templates_directory[path]) return templates_directory[path];
  		return null;
	};
	
	EJS.update = function(path, template) { 
		if(path == null) return;
		templates_directory[path] = template ;
	};
	
	EJS.INVALID_PATH =  -1;
};
EJS.config( {cache: true, type: '<', ext: '.ejs' } );



/**
 * @constructor
 * By adding functions to EJS.Helpers.prototype, those functions will be available in the 
 * views.
 * @init Creates a view helper.  This function is called internally.  You should never call it.
 * @param {Object} data The data passed to the view.  Helpers have access to it through this._data
 */
EJS.Helpers = function(data, extras){
	this._data = data;
    this._extras = extras;
    extend(this, extras );
};
/* @prototype*/
EJS.Helpers.prototype = {
    /**
     * Renders a new view.  If data is passed in, uses that to render the view.
     * @param {Object} options standard options passed to a new view.
     * @param {optional:Object} data
     * @return {String}
     */
	view: function(options, data, helpers){
        if(!helpers) helpers = this._extras
		if(!data) data = this._data;
		return new EJS(options).render(data, helpers);
	},
    /**
     * For a given value, tries to create a human representation.
     * @param {Object} input the value being converted.
     * @param {Object} null_text what text should be present if input == null or undefined, defaults to ''
     * @return {String} 
     */
	to_text: function(input, null_text) {
	    if(input == null || input === undefined) return null_text || '';
	    if(input instanceof Date) return input.toDateString();
		if(input.toString) return input.toString().replace(/\n/g, '<br />').replace(/''/g, "'");
		return '';
	}
};
    EJS.newRequest = function(){
	   var factories = [function() { return new ActiveXObject("Msxml2.XMLHTTP"); },function() { return new XMLHttpRequest(); },function() { return new ActiveXObject("Microsoft.XMLHTTP"); }];
	   for(var i = 0; i < factories.length; i++) {
	        try {
	            var request = factories[i]();
	            if (request != null)  return request;
	        }
	        catch(e) { continue;}
	   }
	}
	
	EJS.request = function(path){
	   var request = new EJS.newRequest()
	   request.open("GET", path, false);
	   
	   try{request.send(null);}
	   catch(e){return null;}
	   
	   if ( request.status == 404 || request.status == 2 ||(request.status == 0 && request.responseText == '') ) return null;
	   
	   return request.responseText
	}
	EJS.ajax_request = function(params){
		params.method = ( params.method ? params.method : 'GET')
		
		var request = new EJS.newRequest();
		request.onreadystatechange = function(){
			if(request.readyState == 4){
				if(request.status == 200){
					params.onComplete(request)
				}else
				{
					params.onComplete(request)
				}
			}
		}
		request.open(params.method, params.url)
		request.send(null)
	}


})();