From a617218f079fb0957658ac9db5fe278ba7d6300e Mon Sep 17 00:00:00 2001
From: Fabien Benetou <fabien@benetou.fr>
Date: Fri, 12 Aug 2011 22:57:23 +0200
Subject: [PATCH] support for multiple types of exercises

---
 pmwiki_recipes/exercises.php | 130 +++++++++++++++++++++--------------
 1 file changed, 77 insertions(+), 53 deletions(-)

diff --git a/pmwiki_recipes/exercises.php b/pmwiki_recipes/exercises.php
index 841c8c0..975bcab 100644
--- a/pmwiki_recipes/exercises.php
+++ b/pmwiki_recipes/exercises.php
@@ -22,72 +22,94 @@ SDV($HandleActions['Exercises'], 'Exercises');
 SDV($HandleAuth['Exercises'],'read');
 
 function Exercises($pagename, $auth){
+	$type = $_GET["type"];
 
-	$exercisetype="pagelink";
-	list($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");
+	$availableexercisetypes = array("pagelink", "expressioninpage");
 
-	}
+	switch ($type){
+		case "pagelink":
+			list($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);
+			//randomly pick a page in the possible pages
+			$sourcepage = $pages[rand(0,count($pages)-1)];
 
-	//$answers = array();
-	//consider pilling up potential in $answers[]
+			$content = ReadPage($sourcepage,READPAGE_CURRENT);
+			//$text = $content["text"];
+			// to use later on for expression exercises
+			$links = $content["targets"];
+			$links_array = explode(",",$links);
 
-	//randomly pick a page amongst the linked pages
-	$pageA = $links_array[rand(0,count($links_array)-1)];
+			//$answers = array();
+			//consider pilling up potential in $answers[]
 
-        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)]);
+			//randomly pick a page amongst the linked pages
+			$pageA = $links_array[rand(0,count($links_array)-1)];
 
-	//display
-	$result .="Is page [[$sourcepage]] linked to ";
-	$counter = (int) $_GET["counter"];
+			unset($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)]);
 
-	$counterparam = "";
-	if ( $counter > 0) {
-		$counterparam = "counter=$counter&";
-	}
+			//display
+			$result .="Is page [[$sourcepage]] linked to ";
+			$counter = (int) $_GET["counter"];
 
-	$answers = array ($pageA,$pageB,$pageC);
-	shuffle($answers);
-	for ($i=0;$i<count($answers);$i++) {
-		if ($answers[$i] != "") {
-			if ( $i == count($answers) -1 )
-				$result .= " or ";
-			//display the groupname everytime only if using AllPages
-			if ($group != "AllPages") {
-				list($currentgroup,$currentpage) = explode(".",$answers[$i]);
-				$result .="[[$pagename?action=ExercisesCheck&".$counterparam
-					."type=$exercisetype&source=$sourcepage&answer=".$answers[$i]."|".$currentpage."]], ";
-			} else {
-				$result .="[[$pagename?action=ExercisesCheck&".$counterparam
-					."type=$exercisetype&source=$sourcepage&answer=".$answers[$i]."|".$answers[$i]."]], ";
+			$counterparam = "";
+			if ( $counter > 0) {
+				$counterparam = "counter=$counter&";
 			}
-		}
+
+			$answers = array ($pageA,$pageB,$pageC);
+			shuffle($answers);
+			for ($i=0;$i<count($answers);$i++) {
+				if ($answers[$i] != "") {
+					if ( $i == count($answers) -1 )
+						$result .= " or ";
+					//display the groupname everytime only if using AllPages
+					if ($group != "AllPages") {
+						list($currentgroup,$currentpage) = explode(".",$answers[$i]);
+						$result .="[[$pagename?action=ExercisesCheck&".$counterparam
+							."type=$type&source=$sourcepage&answer=".$answers[$i]."|".$currentpage."]], ";
+					} else {
+						$result .="[[$pagename?action=ExercisesCheck&".$counterparam
+							."type=$type&source=$sourcepage&answer=".$answers[$i]."|".$answers[$i]."]], ";
+					}
+				}
+			}
+			$result .="? ";
+			$result .="\n\nClick on the answer.";
+			break;
+		case "expressioninpage":
+			// explode content by line "%0a" or word " "
+			$result .= "Does the expression 'EXPRESSION' come from PAGEA PAGEB or PAGEC?";
+			break;
+		default:
+			$result .= "Exercise type unknown.";
 	}
-	$result .="? ";
-	$result .="\n\nClick on the answer.";
 
-	$result .= "\n\nGenerated by [[http://fabien.benetou.fr/MemoryRecalls/ImprovingPIM#PIMBasedExercises|PIM Based Exercises]]";
+	$result .= "\n\nGenerated by [[http://fabien.benetou.fr/MemoryRecalls/ImprovingPIM#PIMBasedExercises|PIM Based Exercises]]. ";
+        unset($availableexercisetypes[array_search($type,$availableexercisetypes)]);
+	if (count($availableexercisetypes) > 0) {
+		$result .= " Try other types of exercises:";
+		foreach ($availableexercisetypes as $e) {
+			$result	.= " [[$pagename?action=Exercises&type=$e|$e]],";
+		}
+		$result .= ".";
+	}
+	if ( $counter > 0) {
+		$result .= " (note that it resets the counter)";
+	}
 	$renderedresult = MarkupToHTML($pagename, $result);
 	print $renderedresult;
 	
@@ -135,6 +157,8 @@ function ExercisesCheck($pagename, $auth){
 				$result .="\n\nTry to redeem yourself by [[$pagename?action=Exercises|trying another time]]. ";
 			}
 			break;
+		default:
+			$result .= "Exercise type unknown.";
 	}
 	$result .= "\n\nGenerated by [[http://fabien.benetou.fr/MemoryRecalls/ImprovingPIM#PIMBasedExercises|PIM Based Exercises]]";
 	$renderedresult = MarkupToHTML($pagename, $result);