// ==UserScript==
// @name           VirtualBlinders
// @namespace      Utopiah
// @description    Stay focus, damnit!
// @include        *youtube.com*
// ==/UserScript==

/* TODO
# handle background tab
## stop timer when focus lost window.onunload or window.onblur
## restart timer when focus is back window.load or window.onfocus
## XXX what is happening when 2 background tabs are increasing the timer?!
# improve the list of websites to include
## consider include * then refine window.location pattern per task
# make timers (default to 0 sec, value defined via the script or a GM_Value) to be more flexible
## reset timer either manually or per day (i.e.) reset if last set date <5AM
## set 2 thresholds, the first as a warning, the second as an action

Note that it does work even when Flash has focus.

*/

var t;
var MODE="video";
var time_spent = GM_getValue(MODE,0);

GM_xmlhttpRequest({
  method: "GET",
  url: "http://fabien.benetou.fr/pub/currenttask",
  onload: function(response) {
    task = response.responseText;
    responseCheck(task);
    }
});

function responseCheck(task) {
	task = 'Reading\n';
	timeThreshold = 600;
	aboveThreshold = ( timeThreshold < time_spent );
	aboveThreshold = false;
	if (task == 'Reading\n' || task == 'Programming\n'){
		if ( !aboveThreshold ) {
			//under threshold, just display a warning and the content
			document.body.innerHTML="You should be focusing on <a href=\"http://fabien.benetou.fr/CognitiveEnvironments/"
				+ task + "\">"
				+ task + "</a> instead,\nare you sure you need that information from that website?"
				+ "<br/>Note that you have already spent <span id='timespent'>"
				+ time_spent + "</span> seconds on that website so far!"
				+ "(which still is under the threshold of "+timeThreshold+" seconds)<hr/>"
				+document.body.innerHTML;
			t=window.setInterval(mytimer,1000);
			//regarding the specific syntax
			//see http://commons.oreilly.com/wiki/index.php/Greasemonkey_Hacks/Getting_Started#Pitfall_.231:_Auto-eval_Strings
			GM_log("register listeners");
			window.addEventListener("blur", stopTimer, true);
			window.addEventListener("focus", restartTimer, true);
			window.addEventListener("unload", setTotalTimeSpent, true);
		} else {
			//above threshold, only display the warning without the content
			document.body.innerHTML="You should be focusing on <a href=\"http://fabien.benetou.fr/CognitiveEnvironments/"
				+ task + "\">"
				+ task + "</a> instead,\nare you sure you need that information from that website?"
				+ "<br/>Note that you have already spent <span id='timespent'>"
				+ time_spent + "</span> seconds on that website so far!<br/>"
				+ "(which is above the allowed threshold of "+timeThreshold+" seconds)<hr/>";
		}
	}
}

function mytimer() {
	//GM_log("timer tick");
	time_spent=time_spent+1;
	//fail document.getElementById('timespent').innerText=time_spent;
}

function stopTimer() {
	GM_log("stop timer");
	window.clearInterval(t);
}

function restartTimer() {
	GM_log("restart timer");
	t=window.setInterval(mytimer,1000);
}

function setTotalTimeSpent() {
	GM_log("set total time spent");
	GM_setValue(MODE,time_spent);
	// probably better to re-read the value then add the time ellapsed since
}