MDL-59411 course: display access restriction in access error message

course/renderer.php

@@ -945,6 +945,34 @@ class core_course_renderer extends plugin_renderer_base {
         return $output;
     }
 
+    /**
+     * Message displayed to the user when they try to access unavailable activity following URL
+     *
+     * This method is a very simplified version of {@link course_section_cm()} to be part of the error
+     * notification only. It also does not check if module is visible on course page or not.
+     *
+     * The message will be displayed inside notification!
+     *
+     * @param cm_info $cm
+     * @return string
+     */
+    public function course_section_cm_unavilable_error_message(cm_info $cm) {
+        if ($cm->uservisible) {
+            return null;
+        }
+        if (!$cm->availableinfo) {
+            return get_string('activityiscurrentlyhidden');
+        }
+
+        $altname = get_accesshide(' ' . $cm->modfullname);
+        $name = html_writer::empty_tag('img', array('src' => $cm->get_icon_url(),
+                'class' => 'iconlarge activityicon', 'alt' => ' ', 'role' => 'presentation')) .
+            html_writer::tag('span', ' '.$cm->get_formatted_name() . $altname, array('class' => 'instancename'));
+        $formattedinfo = \core_availability\info::format_info($cm->availableinfo, $cm->get_course());
+        return html_writer::div($name, 'activityinstance-error') .
+        html_writer::div($formattedinfo, 'availabilityinfo-error');
+    }
+
     /**
      * Renders HTML to display a list of course modules in a course section
      * Also displays "move here" controls in Javascript-disabled mode
@@ -2072,7 +2100,6 @@ class core_course_renderer extends plugin_renderer_base {
                 set_attributes(array('class' => 'frontpage-category-names'));
         return $this->coursecat_tree($chelper, coursecat::get(0));
     }
-
 }
 
 /**

lib/moodlelib.php

@@ -2898,13 +2898,11 @@ function require_login($courseorid = null, $autologinguest = true, $cm = null, $
         if ($preventredirect) {
             throw new require_login_exception('Activity is hidden');
         }
-        if ($course->id != SITEID) {
-            $url = new moodle_url('/course/view.php', array('id' => $course->id));
-        } else {
-            $url = new moodle_url('/');
-        }
-        redirect($url, get_string('activityiscurrentlyhidden'), null,
-                \core\output\notification::NOTIFY_ERROR);
+        // Get the error message that activity is not available and why (if explanation can be shown to the user).
+        $PAGE->set_course($course);
+        $renderer = $PAGE->get_renderer('course');
+        $message = $renderer->course_section_cm_unavilable_error_message($cm);
+        redirect(course_get_url($course), $message, null, \core\output\notification::NOTIFY_ERROR);
     }
 
     // Set the global $COURSE.