/** July 2012. Josh de Leeuw

	This plugin gives the user the ability to execute an arbitrary function
	during an experiment.
	
	Params:
		"type" is "call_function"
		"func" is the function that will be called
		"args" is an array of arguments to pass to the function. (optional)
	
	Data:
		The return value of the function will be stored in the data.
**/

(function( $ ) {
	jsPsych.call_function = (function(){
	
		var plugin = {};
		
		plugin.create = function(params) {
			var trials = new Array(1);
			trials[0] = {
				"type": "call_function",
				"func": params["func"],
				"args": params["args"] || []
			}
			return trials;
		}
		
		plugin.trial = function(display_element, block, trial, part)
		{
			var return_val = trial.func.apply({}, [trial.args]);
			if(return_val){
				block.data[block.trial_idx] = return_val;
			}
			
			block.next();
		}
	
	
		return plugin;
	})();
})(jQuery);