diff --git a/main/gradebook/lib/GradebookUtils.php b/main/gradebook/lib/GradebookUtils.php
index 1263071417..e936c61fdd 100644
--- a/main/gradebook/lib/GradebookUtils.php
+++ b/main/gradebook/lib/GradebookUtils.php
@@ -121,12 +121,18 @@ class GradebookUtils
      */
     public static function build_type_icon_tag($kind, $attributes = array())
     {
-        return Display::return_icon(self::get_icon_file_name($kind), ' ', $attributes, ICON_SIZE_SMALL);
+        return Display::return_icon(
+            self::get_icon_file_name($kind),
+            ' ',
+            $attributes,
+            ICON_SIZE_SMALL
+        );
     }
 
     /**
      * Returns the icon filename for a gradebook item
      * @param string $type value returned by a gradebookitem's get_icon_name()
+     * @return string
      */
     public static function get_icon_file_name($type)
     {
@@ -183,6 +189,7 @@ class GradebookUtils
      * Builds the course or platform admin icons to edit a category
      * @param Category $cat category
      * @param Category $selectcat id of selected category
+     * @return string
      */
     public static function build_edit_icons_cat($cat, $selectcat)
     {
@@ -289,6 +296,7 @@ class GradebookUtils
      * Builds the course or platform admin icons to edit an evaluation
      * @param  Evaluation $eval evaluation object
      * @param int $selectcat id of selected category
+     * @return string
      */
     public static function build_edit_icons_eval($eval, $selectcat)
     {
@@ -302,7 +310,12 @@ class GradebookUtils
             $visibility_icon = ($eval->is_visible() == 0) ? 'invisible' : 'visible';
             $visibility_command = ($eval->is_visible() == 0) ? 'set_visible' : 'set_invisible';
             if ($is_locked && !api_is_platform_admin()) {
-                $modify_icons = Display::return_icon('edit_na.png', get_lang('Modify'), '', ICON_SIZE_SMALL);
+                $modify_icons = Display::return_icon(
+                    'edit_na.png',
+                    get_lang('Modify'),
+                    '',
+                    ICON_SIZE_SMALL
+                );
             } else {
                 $modify_icons = '<a href="gradebook_edit_eval.php?editeval='.$eval->get_id().'&'.$courseParams.'">'.
                     Display::return_icon('edit.png', get_lang('Modify'), '', ICON_SIZE_SMALL).'</a>';
@@ -329,6 +342,8 @@ class GradebookUtils
      * Builds the course or platform admin icons to edit a link
      * @param AbstractLink $link
      * @param int $selectcat id of selected category
+     *
+     * @return string
      */
     public static function build_edit_icons_link($link, $selectcat)
     {
@@ -349,7 +364,12 @@ class GradebookUtils
             $visibility_command = ($link->is_visible() == 0) ? 'set_visible' : 'set_invisible';
 
             if ($is_locked && !api_is_platform_admin()) {
-                $modify_icons = Display::return_icon('edit_na.png', get_lang('Modify'), '', ICON_SIZE_SMALL);
+                $modify_icons = Display::return_icon(
+                    'edit_na.png',
+                    get_lang('Modify'),
+                    '',
+                    ICON_SIZE_SMALL
+                );
             } else {
                 $modify_icons = '<a href="gradebook_edit_link.php?editlink='.$link->get_id().'&'.$courseParams.'">'.
                     Display::return_icon('edit.png', get_lang('Modify'), '', ICON_SIZE_SMALL).'</a>';
@@ -381,8 +401,12 @@ class GradebookUtils
      *
      * @return   array     false on error or array of resource
      */
-    public static function isResourceInCourseGradebook($course_code, $resource_type, $resource_id, $session_id = 0)
-    {
+    public static function isResourceInCourseGradebook(
+        $course_code,
+        $resource_type,
+        $resource_id,
+        $session_id = 0
+    ) {
         $table = Database::get_main_table(TABLE_MAIN_GRADEBOOK_LINK);
         $course_code = Database::escape_string($course_code);
         $sql = "SELECT * FROM $table l
@@ -663,8 +687,14 @@ class GradebookUtils
     public static function get_list_gradebook_certificates_by_user_id($user_id, $cat_id = null)
     {
         $table_certificate = Database::get_main_table(TABLE_MAIN_GRADEBOOK_CERTIFICATE);
-        $sql = 'SELECT gc.score_certificate, gc.created_at, gc.path_certificate, gc.cat_id, gc.user_id, gc.id
-                FROM  ' . $table_certificate.' gc
+        $sql = 'SELECT 
+                    gc.score_certificate, 
+                    gc.created_at, 
+                    gc.path_certificate, 
+                    gc.cat_id, 
+                    gc.user_id, 
+                    gc.id
+                FROM  '.$table_certificate.' gc
                 WHERE gc.user_id="' . intval($user_id).'" ';
         if (!is_null($cat_id) && $cat_id > 0) {
             $sql .= ' AND cat_id='.intval($cat_id);
@@ -781,7 +811,6 @@ class GradebookUtils
                 $default_weight_setting = api_get_setting('gradebook_default_weight');
                 $default_weight = isset($default_weight_setting) && !empty($default_weight_setting) ? $default_weight_setting : 100;
                 $cat->set_weight($default_weight);
-
                 $cat->set_grade_model_id($gradebook_model_id);
                 $cat->set_certificate_min_score(75);
 
@@ -994,12 +1023,14 @@ class GradebookUtils
             $counter++;
             $badges[] = Display::badge($value, $class);
         }
+
         return Display::badge_group($badges);
     }
 
     /**
      * returns users within a course given by param
      * @param string $courseCode
+     * @return array
      */
     public static function get_users_in_course($courseCode)
     {
@@ -1251,7 +1282,6 @@ class GradebookUtils
     {
         $userId = intval($userId);
         $courseList = [];
-
         $courses = CourseManager::get_courses_list_by_user_id($userId);
 
         foreach ($courses as $course) {
@@ -1293,7 +1323,7 @@ class GradebookUtils
     /**
      * Get the achieved certificates for a user in course sessions
      * @param int $userId The user id
-     * @param bool $includeNonPublicCertificates Whether include the non-plublic certificates
+     * @param bool $includeNonPublicCertificates Whether include the non-public certificates
      * @return array
      */
     public static function getUserCertificatesInSessions($userId, $includeNonPublicCertificates = true)
@@ -1332,7 +1362,6 @@ class GradebookUtils
                 }
 
                 $courseGradebookId = $courseGradebookCategory[0]->get_id();
-
                 $certificateInfo = self::get_certificate_by_user_id(
                     $courseGradebookId,
                     $userId
diff --git a/main/gradebook/lib/gradebook_result.class.php b/main/gradebook/lib/gradebook_result.class.php
index af04cbac80..7f5fb6452b 100644
--- a/main/gradebook/lib/gradebook_result.class.php
+++ b/main/gradebook/lib/gradebook_result.class.php
@@ -20,10 +20,8 @@ class GradeBookResult
 
     /**
      * Exports the complete report as a CSV file
-     * @param	string		Document path inside the document tool
-     * @param	integer		Optional user ID
-     * @param	boolean		Whether to include user fields or not
-     * @return	boolean		False on error
+     * @param    string $dato Document path inside the document tool
+     * @return    boolean        False on error
      */
     public function exportCompleteReportCSV($dato)
     {
@@ -75,6 +73,7 @@ class GradeBookResult
 
     /**
      * Exports the complete report as an XLS file
+     * @param array $data
      * @return	boolean|null		False on error
      */
     public function exportCompleteReportXLS($data)
@@ -119,7 +118,7 @@ class GradeBookResult
 
     /**
      * Exports the complete report as a DOCX file
-     * @param $data The table data
+     * @param array $data The table data
      * @return bool
      */
     public function exportCompleteReportDOC($data)
diff --git a/main/gradebook/lib/user_data_generator.class.php b/main/gradebook/lib/user_data_generator.class.php
index 62e99376a2..22d4ef51a8 100755
--- a/main/gradebook/lib/user_data_generator.class.php
+++ b/main/gradebook/lib/user_data_generator.class.php
@@ -30,6 +30,12 @@ class UserDataGenerator
     private $scorecache;
     private $avgcache;
 
+    /**
+     * UserDataGenerator constructor.
+     * @param int $userid
+     * @param array $evals
+     * @param array $links
+     */
     public function __construct($userid, $evals = array(), $links = array())
     {
         $this->userid = $userid;
@@ -95,7 +101,7 @@ class UserDataGenerator
         // sort users array
         if ($sorting & self::UDG_SORT_TYPE) {
             usort($allitems, array('UserDataGenerator', 'sort_by_type'));
-        }elseif ($sorting & self::UDG_SORT_NAME) {
+        } elseif ($sorting & self::UDG_SORT_NAME) {
             usort($allitems, array('UserDataGenerator', 'sort_by_name'));
         } elseif ($sorting & self::UDG_SORT_COURSE) {
             usort($allitems, array('UserDataGenerator', 'sort_by_course'));
@@ -130,7 +136,7 @@ class UserDataGenerator
         $visibleitems = array_slice($allitems, $start, $count);
 
         // fill score cache if not done yet
-        if (!isset ($this->scorecache)) {
+        if (!isset($this->scorecache)) {
             foreach ($visibleitems as $item) {
                 $this->scorecache[$item->get_item_type().$item->get_id()]
                     = $item->calc_score($this->userid);
@@ -148,8 +154,9 @@ class UserDataGenerator
             $row[] = $this->build_category_name($item);
             $row[] = $this->build_average_column($item, $ignore_score_color);
             $row[] = $this->build_result_column($item, $ignore_score_color);
-            if ($scoredisplay->is_custom())
+            if ($scoredisplay->is_custom()) {
                 $row[] = $this->build_mask_column($item, $ignore_score_color);
+            }
             $data[] = $row;
         }
         return $data;
@@ -343,7 +350,7 @@ class UserDataGenerator
      */
     private function get_course_name_from_code_cached($coursecode)
     {
-        if (isset ($this->coursecodecache) && isset ($this->coursecodecache[$coursecode])) {
+        if (isset($this->coursecodecache) && isset($this->coursecodecache[$coursecode])) {
             return $this->coursecodecache[$coursecode];
         } else {
             $name = CourseManager::getCourseNameFromCode($coursecode);
@@ -358,7 +365,7 @@ class UserDataGenerator
      */
     private function get_category_cached($category_id)
     {
-        if (isset ($this->categorycache) && isset ($this->categorycache[$category_id])) {
+        if (isset($this->categorycache) && isset ($this->categorycache[$category_id])) {
             return $this->categorycache[$category_id];
         } else {
             $cat = Category::load($category_id);