// timing parameters: [length to show feedback, intertrial gap, optional length to display target]
// if optional length to display target is missing, then target is displayed until subject responds.

//TODO 
// option to keep stim on screen during feedback
// way to provide corrective feedback

function cf_create(params)
{
	cf_stims = params["stimuli"];
	trials = new Array(cf_stims.length);
	for(var i = 0; i < trials.length; i++)
	{
		trials[i] = {};
		trials[i]["type"] = "cf";
		trials[i]["a_path"] = cf_stims[i];
		trials[i]["timing"] = params["timing"];
		trials[i]["key_answer"] = params["key_answer"][i];
		trials[i]["text_answer"] = params["text_answer"][i];
		trials[i]["choices"] = params["choices"];
		trials[i]["correct_text"] = params["correct_text"];
		trials[i]["incorrect_text"] = params["incorrect_text"];
		trials[i]["show_stim_feedback"] = params["show_stim_feedback"];
		if(params["prompt"] != undefined){
			trials[i]["prompt"] = params["prompt"];
		}
		if(params["data"]!=undefined){
			trials[i]["data"] = params["data"][i];
		}
	}
	return trials;
}

function cf_trial($this, block, trial, part)
{
	//console.log(block.trial_idx);
	switch(part){
		case 1:
			p1_time = (new Date()).getTime();
			$.fn.jsPsych.showImage($this, trial.a_path, 'cf');
			if(trial.timing[2]!=undefined){
				setTimeout(cf_trial, trial.timing[2], $this, block, trial, part + 1);
			} else {
				//show prompt here
				$this.append(trial.prompt);
				cf_trial($this, block, trial, part + 1);
			}
			break;
		case 2:
			p2_time = (new Date()).getTime();
			if(trial.timing[2]!=undefined){
				$('.cf').remove();
				$this.html(trial.prompt);
			}
			startTime = (new Date()).getTime();
			var resp_func = function(e) {
				var flag = false;
				var correct = false;
				if(e.which==trial.key_answer) // correct category
				{
					flag = true;
					correct = true;
				} 
				else
				{
					// check if the key is any of the options, or if it is an accidental keystroke
					for(var i=0;i<trial.choices.length;i++)
					{
						if(e.which==trial.choices[i])
						{ 
							flag = true;
							correct = false;
						}
					}
				}
				if(flag)
				{
					endTime = (new Date()).getTime();
					rt = (endTime-startTime);
					stim1_time = (p2_time-p1_time);
					var trial_data = {"rt": rt, "correct": correct, "a_path": trial.a_path, "key_press": e.which, "stim1_time": stim1_time}
					block.data[block.trial_idx] = $.extend({},trial_data,trial.data);
					$(document).unbind('keyup',resp_func);
					$('.cf').remove();
					$this.html('');
					cf_trial($this, block, trial, part + 1);
				}
			}
			$(document).keyup(resp_func);
			break;
		case 3:
			if(trial.show_stim_feedback)
			{
				$.fn.jsPsych.showImage($this, trial.a_path, 'cf');
			}
			// give feedback
			var atext = "";
			if(block.data[block.trial_idx]["correct"])
			{
				atext = trial.correct_text.replace("&ANS&", trial.text_answer);
			} else {
				atext = trial.incorrect_text.replace("&ANS&", trial.text_answer);
			}
			$this.append(atext);
			setTimeout(cf_trial, trial.timing[0], $this, block, trial, part + 1);
			break;
		case 4:
			$this.html("");
			setTimeout(function(b){b.next();}, trial.timing[1], block);
			break;
	}
}