From 00a342341c494cf8178756bd338fa42a19e15575 Mon Sep 17 00:00:00 2001
From: Frederic Massart <fred@moodle.com>
Date: Wed, 7 Nov 2012 15:13:07 +0800
Subject: [PATCH] MDL-36417 course: Toggling section visibility update module
 visibility

---
 course/lib.php | 54 ++++++++++++++++++++++++++++++++------------------
 1 file changed, 35 insertions(+), 19 deletions(-)

diff --git a/course/lib.php b/course/lib.php
index a772578334c..fc53eafba86 100644
--- a/course/lib.php
+++ b/course/lib.php
@@ -1272,7 +1272,16 @@ function set_section_visible($courseid, $sectionnumber, $visibility) {
         if (!empty($section->sequence)) {
             $modules = explode(",", $section->sequence);
             foreach ($modules as $moduleid) {
-                set_coursemodule_visible($moduleid, $visibility, true);
+                if ($cm = $DB->get_record('course_modules', array('id' => $moduleid), 'visible, visibleold')) {
+                    if ($visibility) {
+                        // As we unhide the section, we use the previously saved visibility stored in visibleold.
+                        set_coursemodule_visible($moduleid, $cm->visibleold);
+                    } else {
+                        // We hide the section, so we hide the module but we store the original state in visibleold.
+                        set_coursemodule_visible($moduleid, 0);
+                        $DB->set_field('course_modules', 'visibleold', $cm->visible, array('id' => $moduleid));
+                    }
+                }
             }
         }
         rebuild_course_cache($courseid, true);
@@ -2806,16 +2815,26 @@ function set_coursemodule_idnumber($id, $idnumber) {
 }
 
 /**
-* $prevstateoverrides = true will set the visibility of the course module
-* to what is defined in visibleold. This enables us to remember the current
-* visibility when making a whole section hidden, so that when we toggle
-* that section back to visible, we are able to return the visibility of
-* the course module back to what it was originally.
-*/
-function set_coursemodule_visible($id, $visible, $prevstateoverrides=false) {
+ * Set the visibility of a module and inherent properties.
+ *
+ * From 2.4 the parameter $prevstateoverrides has been removed, the logic it triggered
+ * has been moved to {@link set_section_visible()} which was the only place from which
+ * the parameter was used.
+ *
+ * @param int $id of the module
+ * @param int $visible state of the module
+ * @return bool false when the module was not found, true otherwise
+ */
+function set_coursemodule_visible($id, $visible) {
     global $DB, $CFG;
     require_once($CFG->libdir.'/gradelib.php');
 
+    // Trigger developer's attention when using the previously removed argument.
+    if (func_num_args() > 2) {
+        debugging('Wrong number of arguments passed to set_coursemodule_visible(), $prevstateoverrides
+            has been removed.', DEBUG_DEVELOPER);
+    }
+
     if (!$cm = $DB->get_record('course_modules', array('id'=>$id))) {
         return false;
     }
@@ -2840,17 +2859,14 @@ function set_coursemodule_visible($id, $visible, $prevstateoverrides=false) {
         }
     }
 
-    if ($prevstateoverrides) {
-        if ($visible == '0') {
-            // Remember the current visible state so we can toggle this back.
-            $DB->set_field('course_modules', 'visibleold', $cm->visible, array('id'=>$id));
-        } else {
-            // Get the previous saved visible states.
-            $DB->set_field('course_modules', 'visible', $cm->visibleold, array('id'=>$id));
-        }
-    } else {
-        $DB->set_field("course_modules", "visible", $visible, array("id"=>$id));
-    }
+    // Updating visible and visibleold to keep them in sync. Only changing a section visibility will
+    // affect visibleold to allow for an original visibility restore. See set_section_visible().
+    $cminfo = new stdClass();
+    $cminfo->id = $id;
+    $cminfo->visible = $visible;
+    $cminfo->visibleold = $visible;
+    $DB->update_record('course_modules', $cminfo);
+
     rebuild_course_cache($cm->course, true);
     return true;
 }