package pier.util
{
	public class Template
	{		
		//RegExp to find #{variable_name}
		private var _pattern:RegExp = new RegExp("(^|.|\r|\n)(#\{(.*?)\})", "im");
		private var _template:String;
		private var _template_original:String;
		//_obj is the Object hash containing the data to insert into the report string
		private var _obj:Object;
		
		public function Template(template:String):void
		{
			_template_original = template;
		}
		
		public function evaluate(obj:Object):String {
			//do this so you don't overwrite the original template :: subsequent calls would fail otherwise
			_template = new String(_template_original);
			//start the actual evaluation loop
			var result:String = doEvaluate(obj);
			return result;
		}
		
		private function doEvaluate(obj:Object):String {
			_obj = obj;
			//replace the match found in the report with the hash property
			_template = _template.replace(_pattern, insertTxt);
			//if another match was found continue the loop
			if(_template.match(_pattern)){
				_template = this.doEvaluate(_obj);
			}
			_obj = null;
			return _template;
		}
		
		private function insertTxt():String
		{
			//third argument  is the variable located in the hash
			if(_obj[arguments[3]]) {
				return _obj[arguments[3]];
			}
			else {
				return "";
			}
		}
		
	}
}