Fixing more issues from the link delete function see #5229

main/exercice/exercice.php

@@ -532,10 +532,12 @@ if ($is_allowedToEdit) {
 					$sql = 'SELECT gl.id FROM ' . $tbl_grade_link . ' gl WHERE gl.type="1" AND gl.ref_id="' . $exerciseId . '";';
 					$result = Database::query($sql, __FILE__, __LINE__);
 					$row = Database :: fetch_array($result, 'ASSOC');
-
+					//see 
+					if (!empty($row['id'])) {
                  		$link = LinkFactory :: load($row['id']);
                      		if ($link[0] != null) {
                             	$link[0]->delete();
+                     		}
            			}
 					Display :: display_confirmation_message(get_lang('ExerciseDeleted'));
 					break;

main/gradebook/gradebook.php

@@ -269,6 +269,8 @@ if (isset ($_GET['visiblelink'])) {
 }
 if (isset ($_GET['deletelink'])) {
 	block_students();
+	//fixing #5229
+	if (!empty($_GET['deletelink'])) {	
 		$link= LinkFactory :: load(Security::remove_XSS($_GET['deletelink']));
 		if ($link[0] != null) {
 			$sql='UPDATE '.$tbl_forum_thread.' SET thread_qualify_max=0,thread_weight=0,thread_title_qualify="" WHERE thread_id=(SELECT ref_id FROM '.$tbl_grade_links.' where id='.Security::remove_XSS($_GET['deletelink']).');';
@@ -279,6 +281,7 @@ if (isset ($_GET['deletelink'])) {
 		$confirmation_message = get_lang('LinkDeleted');
 		$filter_confirm_msg = false;
 	}
+}
 $course_to_crsind = isset ($course_to_crsind) ? $course_to_crsind : '';
 if ($course_to_crsind && !isset($_GET['confirm'])) {
 	block_students();
@@ -328,13 +331,16 @@ if (isset ($_POST['action'])) {
 						$number_of_deleted_evaluations++;
 					}
 					if (api_substr($indexstr, 0, 4) == 'LINK') {
-						$link= LinkFactory :: load(api_substr($indexstr, 4));
+						$id = api_substr($indexstr, 4);
+						if (!empty($id)) {
+							$link= LinkFactory :: load();
 							if ($link[0] != null) {
 								$link[0]->delete();
 							}
 							$number_of_deleted_links++;
 						}
 					}
+				}
 				$confirmation_message = get_lang('DeletedCategories') . ' : <b>' . $number_of_deleted_categories . '</b><br />' . get_lang('DeletedEvaluations') . ' : <b>' . $number_of_deleted_evaluations . '</b><br />' . get_lang('DeletedLinks') . ' : <b>' . $number_of_deleted_links . '</b><br /><br />' . get_lang('TotalItems') . ' : <b>' . $number_of_selected_items . '</b>';
 				$filter_confirm_msg = false;
 				break;

main/gradebook/index.php

@@ -327,6 +327,8 @@ if (isset ($_GET['visiblelink'])) {
 if (isset ($_GET['deletelink'])) {
 	block_students();
 	$get_delete_link=Security::remove_XSS($_GET['deletelink']);
+	//fixing #5229
+	if (!empty($get_delete_link)) {
 		$link= LinkFactory :: load($get_delete_link);
 		if ($link[0] != null) {
 			$sql='UPDATE '.$tbl_forum_thread.' SET thread_qualify_max=0,thread_weight=0,thread_title_qualify="" WHERE thread_id=(SELECT ref_id FROM '.$tbl_grade_links.' where id='.$get_delete_link.');';
@@ -337,6 +339,7 @@ if (isset ($_GET['deletelink'])) {
 		$confirmation_message = get_lang('LinkDeleted');
 		$filter_confirm_msg = false;
 	}
+}
 
 if (!empty($course_to_crsind) && !isset($_GET['confirm'])) {
 	block_students();
@@ -387,14 +390,17 @@ if (isset ($_POST['action'])) {
 						$number_of_deleted_evaluations++;
 					}
 					if (substr($indexstr, 0, 4) == 'LINK') {
-						$link= LinkFactory :: load(substr($indexstr, 4));
+						//fixing #5229
+						$id = substr($indexstr, 4);
+						if (!empty($id)) {
+							$link= LinkFactory :: load($id);
 							if ($link[0] != null) {
 								$link[0]->delete();
 							}
-
 							$number_of_deleted_links++;
 						}
 					}
+				}
 				$confirmation_message = get_lang('DeletedCategories') . ' : <b>' . $number_of_deleted_categories . '</b><br />' . get_lang('DeletedEvaluations') . ' : <b>' . $number_of_deleted_evaluations . '</b><br />' . get_lang('DeletedLinks') . ' : <b>' . $number_of_deleted_links . '</b><br /><br />' . get_lang('TotalItems') . ' : <b>' . $number_of_selected_items . '</b>';
 				$filter_confirm_msg = false;
 				break;

main/newscorm/learnpath.class.php

@@ -883,10 +883,15 @@ class learnpath {
 		$sql = 'SELECT gl.id FROM ' . $tbl_grade_link . ' gl WHERE gl.type="4" AND gl.ref_id="' . $id . '";';
 		$result = Database::query($sql, __FILE__, __LINE__);
 		$row = Database :: fetch_array($result, 'ASSOC');
+		
+		//fixing gradebook link deleted see #5229
+		if (!empty($row['id'])) {
 	   		$link = LinkFactory :: load($row['id']);
 	    	if ($link[0] != null) {
 	       		$link[0]->delete();
 	    	}
+		}
+		
 		//TODO: also delete items and item-views
 		if (api_get_setting('search_enabled') == 'true') {
 			require_once (api_get_path(LIBRARY_PATH) . 'specific_fields_manager.lib.php');