<?php 

# generate exercises based on wiki content and its structure
# 
# still to implement (cf http://fabien.benetou.fr/Cookbook/Cognition#DailyExercisesFeed )
#	is word X from page A, B, C or D?
#	does page A contains word X, Y or Z?
#	is page A linked to page B?
#	what is the correct order for pages A, B and C on descending criteria i A>B>C? A>C>B? B>C>A? B>A>C? C>B>A? C>A>B?
#		e.g. size, frequency update, last edition, ... 
#	which of those page corresponds the updates visualization V, A, B or C? 
#	keyword or URL in pages
#	page linked to other page
# to display, especially the current and past score in
#	http://fabien.benetou.fr/Content/MentalExercises
# display global or related to the current page, or group (based on parameters)
# cf also early August discussion on ##pim
#
# update http://fabien.benetou.fr/MemoryRecalls/ImprovingPIM when it is working
#	also push to the code repository


$RecipeInfo['Exercises']['Version'] = '2011-12-08';

$HandleActions['Exercises'] = 'Exercises';
$HandleAuth['Exercises'] = 'read';

function Exercises($pagename, $auth){

	$exercisetype="pagelink";
	list($group,$page) = explode(".",$pagename);
	// the pattern should be improve, e.g. remove PmWiki. , RecentChanges, GroupFooter, GroupHeader, Template, ...
	if ($group == "AllPages"){
		// equivalent to getting ALL pages
	        $pages = ListPages();
	} else {
	        $pages = ListPages("/$group\./e");

	}

	//randomly pick a page in the possible pages
	$sourcepage = $pages[rand(0,count($pages))];
	// -1?

	$content = ReadPage($sourcepage,READPAGE_CURRENT);
	//$text = $content["text"];
	// to use later on for expression exercises
	$links = $content["targets"];
	$links_array = explode(",",$links);

	//$answers = array();
	//consider pilling up potential in $answers[]

	//randomly pick a page amongst the linked pages
	$pageA = $links_array[rand(0,count($links_array)-1)];

        unset($pages[array_search($pageA,$links_array)]);
        unset($pages[array_search($pageA,$pages)]);
	//randomly pick 2 others pages which are not amongst the list of linked page
	$pageB = $pages[rand(0,count($pages)-1)];
        unset($pages[array_search($pageB,$pages)]);
	$pageC = $pages[rand(0,count($pages)-1)];
        unset($pages[array_search($pageC,$pages)]);

	//display
	$result .="Is page [[$sourcepage]] linked to ";
	$counter = (int) $_GET["counter"];

	$counterparam = "";
	if ( $counter > 0) {
		$counterparam = "counter=$counter&";
	}

	$answers = array ($pageA,$pageB,$pageC);
	shuffle($answers);
	for ($i=0;$i<count($answers);$i++) {
		if ( $i == count($answers) -1 )
			$result .= " or ";
		$result .="[[$pagename?action=ExercisesCheck&".$counterparam."type=$exercisetype&source=$sourcepage&answer=".$answers[$i]."|".$answers[$i]."]],";
	}
	$result .="? ";

	$renderedresult = MarkupToHTML($pagename, $result);
	print $renderedresult;
	
	//$text = RetrieveAuthSection($pagename,$auth);
	//$content = MarkupToHTML($pagename, $text);
	//print $content;
}

$HandleActions['ExercisesCheck'] = 'ExercisesCheck';
$HandleAuth['ExercisesCheck'] = 'read';

function ExercisesCheck($pagename, $auth){
	$type = $_GET["type"];
	// assuming pagelink
	$sourcepage = $_GET["source"];
	$answer = $_GET["answer"];
	$counter = (int) $_GET["counter"];

	list($group,$page) = explode(".",$pagename);
	if ($group == "AllPages"){
		// equivalent to getting ALL pages
	        $pages = ListPages();
	} else {
	        $pages = ListPages("/$group\./e");
	}
	$content = ReadPage($sourcepage,READPAGE_CURRENT);
	$links = $content["targets"];
	$links_array = explode(",",$links);

	if ( in_array($answer,$links_array) ) {
		$result .="Excellent! [[$sourcepage]] is indeed linked to [[$answer]]. ";
		$result .="Note that $links also are. ";
		if ( $counter > 0) {
			$counter++;
			$result .="See if you can [[$pagename?action=Exercises&counter=$counter|solve yet another one]]. ";
		} else {
			$result .="See if you can [[$pagename?action=Exercises&counter=1|solve yet another one]]. ";
		}
	} else {
		$result .="No, [[$sourcepage]] is not linked to [[$answer]] ";
		$result .="but $links are. ";
		$result .="Try to redeem yourself by [[$pagename?action=Exercises|trying another time]]. ";
	}
	$renderedresult = MarkupToHTML($pagename, $result);
	print $renderedresult;

	//$text = RetrieveAuthSection($pagename,$auth);
	//$content = MarkupToHTML($pagename, $text);
	//print $content;
}

?>