diff --git a/server/moodle/mod/homework/amd/src/homeworkchooser.js b/server/moodle/mod/homework/amd/src/homeworkchooser.js
index 350c42f34..8b706e6e3 100644
--- a/server/moodle/mod/homework/amd/src/homeworkchooser.js
+++ b/server/moodle/mod/homework/amd/src/homeworkchooser.js
@@ -4,9 +4,9 @@ import MyModal from 'mod_homework/modal_homework';
 import ModalEvents from 'core/modal_events';
 
 /**
- * homework/amd/src/homeworkchooser.js
+ * Homework/amd/src/modal_homework.js
  *
- * @package   mod_homework
+ * @package
  * @copyright 2024, cs-24-sw-5-01 <cs-24-sw-5-01@student.aau.dk>
  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  *
@@ -14,11 +14,11 @@ import ModalEvents from 'core/modal_events';
 
 /**
  * Initializes the Homework Chooser Modal.
- *
- * @param {int} cmid - Course Module ID
- * @param {string} title - Title for the modal
+ * @param {int} cmid
+ * @param {string} title
+ * @returns {Promise<void>}
  */
-export const init = async (cmid, title) => {
+export const init = async(cmid, title) => {
     $('#open-homework-chooser').on('click', () => {
         Ajax.call([{
             methodname: 'mod_homework_get_homework_chooser',
@@ -27,33 +27,32 @@ export const init = async (cmid, title) => {
                 const modal = await MyModal.create({
                     title: title,
                     body: `${response.html}`,
-                    // footer: 'An example footer content',
                     large: true,
                     removeOnClose: true,
                 });
 
-                // Show the modal
-                modal.show();
+                // Show the modal.
+                await modal.show();
 
-                // Initialize elements once the modal content is rendered
+                // Initialize elements once the modal content is rendered.
                 modal.getRoot().on(ModalEvents.shown, () => {
-                    // Initialize the elements after modal is displayed
+                    // Initialize the elements after modal is displayed.
                     const startPageInput = modal.getRoot().find('#startPage')[0];
                     const endPageInput = modal.getRoot().find('#endPage')[0];
                     const radioButtons = modal.getRoot().find('input[name="option"]');
                     const testTextarea = modal.getRoot().find('#page-range-input')[0];
                     const testLink = modal.getRoot().find('#linkDiv')[0];
 
-                    // Attach event listeners for page input validation
+                    // Attach event listeners for page input validation.
                     startPageInput.addEventListener('input', validatePageRange);
                     endPageInput.addEventListener('input', validatePageRange);
 
-                    // Attach event listeners for radio buttons
+                    // Attach event listeners for radio buttons.
                     radioButtons.each((_, radio) => {
                         radio.addEventListener('change', toggleInputs);
                     });
 
-                    // Function to validate page range
+                    // Function to validate page range.
                     /**
                      *
                      */
@@ -72,7 +71,7 @@ export const init = async (cmid, title) => {
                         }
                     }
 
-                    // Function to toggle between text and link inputs
+                    // Function to toggle between text and link inputs.
                     /**
                      *
                      */
@@ -87,11 +86,6 @@ export const init = async (cmid, title) => {
                     }
                 });
 
-                // Attach an event listener to handle the modal hidden event
-                modal.getRoot().on(ModalEvents.hidden, () => {
-                    console.log('Modal closed!');
-                });
-
                 // Attach event listeners for buttons
                 modal.getRoot().on('click', '[data-action="submit"]', (e) => {
                     e.preventDefault();
@@ -104,7 +98,7 @@ export const init = async (cmid, title) => {
                 });
             },
             fail: (error) => {
-                console.error("Failed to load homework chooser content:", error);
+                throw new Error(`Failed to load homework chooser content: ${error}`);
             }
         }]);
     });
@@ -118,53 +112,51 @@ export const init = async (cmid, title) => {
 const handleFormSubmit = (modal) => {
     let inputField = modal.getRoot().find('#inputField').val();
 
-    if (inputField === "") {
-        alert("Please fill in input field.");
-        return;
+    if (inputField.value === "") {
+        inputField.setCustomValidity("Please fill in the input field.");
+        inputField.reportValidity(); // Shows the custom message
+        event.preventDefault(); // Prevents form submission
+    } else {
+        inputField.setCustomValidity(""); // Clear the custom message
     }
 
     if (modal.getRoot().find('#option1').is(':checked')) {
-
         let startPage = modal.getRoot().find('#startPage').val();
         let endPage = modal.getRoot().find('#endPage').val();
 
-        // AJAX call to send data to the server
+        // AJAX call to send data to the server.
         Ajax.call([{
-            methodname: 'mod_homework_save_homework_literature',  // Your PHP function that will handle the data
+            methodname: 'mod_homework_save_homework_literature',
             args: {
                 inputfield: inputField,
                 startpage: startPage,
                 endpage: endPage,
             },
-            done: function(response) {
-                console.log("Data saved successfully:", response);
-                // Close the modal after successful submission
+            done: function() {
+                // Close the modal after successful submission.
                 modal.hide();
             },
             fail: function(error) {
-                console.error("Failed to save data:", error);
+                throw new Error(`Failed to save data: ${error}`);
             }
         }]);
-
     } else if (modal.getRoot().find('#option2').is(':checked')) {
-
         let link = modal.getRoot().find('#link').val();
 
-        // AJAX call to send data to the server
+        // AJAX call to send data to the server.
         Ajax.call([{
-            methodname: 'mod_homework_save_homework_link',  // Your PHP function that will handle the data
+            methodname: 'mod_homework_save_homework_link',
             args: {
                 inputfield: inputField,
                 link: link,
             },
-            done: function(response) {
-                console.log("Data saved successfully:", response);
-                // Close the modal after successful submission
+            done: function() {
+                // Close the modal after successful submission.
                 modal.hide();
             },
             fail: function(error) {
-                console.error("Failed to save data:", error);
+                throw new Error(`Failed to save data: ${error}`);
             }
         }]);
     }
-};
\ No newline at end of file
+};
diff --git a/server/moodle/mod/homework/amd/src/modal_homework.js b/server/moodle/mod/homework/amd/src/modal_homework.js
index d5d104faa..44827e687 100644
--- a/server/moodle/mod/homework/amd/src/modal_homework.js
+++ b/server/moodle/mod/homework/amd/src/modal_homework.js
@@ -1,9 +1,9 @@
 import Modal from 'core/modal';
 
 /**
- * homework/amd/src/modal_homework.js
+ * Homework/amd/src/modal_homework.js
  *
- * @package   mod_homework
+ * @package
  * @copyright 2024, cs-24-sw-5-01 <cs-24-sw-5-01@student.aau.dk>
  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  *
diff --git a/server/moodle/mod/homework/db/upgrade.php b/server/moodle/mod/homework/db/upgrade.php
index 7ca3dfb7d..15ac90627 100644
--- a/server/moodle/mod/homework/db/upgrade.php
+++ b/server/moodle/mod/homework/db/upgrade.php
@@ -21,7 +21,7 @@
  * @copyright 2024, cs-24-sw-5-01 <cs-24-sw-5-01@student.aau.dk>
  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
-function xmldb_homework_upgrade($oldversion) {
+function xmldb_homework_upgrade($oldversion): bool {
     global $DB;
 
     $dbman = $DB->get_manager();
@@ -32,16 +32,82 @@ function xmldb_homework_upgrade($oldversion) {
         $table = new xmldb_table('homework');
 
         // Adding fields to table homework.
-        $table->add_field('id', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, XMLDB_SEQUENCE, null, 'Standard Moodle primary key');
-        $table->add_field('name', XMLDB_TYPE_CHAR, '255', null, XMLDB_NOTNULL, null, null, 'Name of the homework');
-        $table->add_field('intro', XMLDB_TYPE_TEXT, null, null, null, null, null, 'Introduction text for the homework');
-        $table->add_field('introformat', XMLDB_TYPE_INTEGER, '4', null, XMLDB_NOTNULL, null, '0', 'Format of the introduction text');
-        $table->add_field('timecreated', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, null, 'Timestamp when the record was created');
-        $table->add_field('timemodified', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, null, 'Timestamp when the record was last modified');
-        $table->add_field('duedate', XMLDB_TYPE_INTEGER, '10', null, null, null, null);
+        $table->add_field(
+            'id',
+            XMLDB_TYPE_INTEGER,
+            '10',
+            null,
+            XMLDB_NOTNULL,
+            XMLDB_SEQUENCE,
+            null,
+            'Standard Moodle primary key'
+        );
+        $table->add_field(
+            'name',
+            XMLDB_TYPE_CHAR,
+            '255',
+            null,
+            XMLDB_NOTNULL,
+            null,
+            null,
+            'Name of the homework'
+        );
+        $table->add_field(
+            'intro',
+            XMLDB_TYPE_TEXT,
+            null,
+            null,
+            null,
+            null,
+            null,
+            'Introduction text for the homework'
+        );
+        $table->add_field(
+            'introformat',
+            XMLDB_TYPE_INTEGER,
+            '4',
+            null,
+            XMLDB_NOTNULL,
+            null,
+            '0',
+            'Format of the introduction text'
+        );
+        $table->add_field(
+            'timecreated',
+            XMLDB_TYPE_INTEGER,
+            '10',
+            null,
+            XMLDB_NOTNULL,
+            null,
+            null,
+            'Timestamp when the record was created'
+        );
+        $table->add_field(
+            'timemodified',
+            XMLDB_TYPE_INTEGER,
+            '10',
+            null,
+            XMLDB_NOTNULL,
+            null,
+            null,
+            'Timestamp when the record was last modified'
+        );
+        $table->add_field(
+            'duedate',
+            XMLDB_TYPE_INTEGER,
+            '10',
+            null,
+            null,
+            null,
+            null
+        );
 
         // Adding keys to table homework.
-        $table->add_key('primary', XMLDB_KEY_PRIMARY, ['id']);
+        $table->add_key(
+            'primary',
+            XMLDB_KEY_PRIMARY,
+            ['id']
+        );
 
         // Conditionally launch create table for homework.
         if (!$dbman->table_exists($table)) {
@@ -52,16 +118,83 @@ function xmldb_homework_upgrade($oldversion) {
         $table = new xmldb_table('homework_literature');
 
         // Adding fields to table homework_literature.
-        $table->add_field('id', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, XMLDB_SEQUENCE, null, 'Standard Moodle primary key');
-        $table->add_field('description', XMLDB_TYPE_TEXT, null, null, null, null, null, 'Description of the homework literature');
-        $table->add_field('startpage', XMLDB_TYPE_INTEGER, '10', null, null, null, null, 'Start page number');
-        $table->add_field('endpage', XMLDB_TYPE_INTEGER, '10', null, null, null, null, 'End page number');
-        $table->add_field('introformat', XMLDB_TYPE_INTEGER, '4', null, XMLDB_NOTNULL, null, '0', 'Format of the introduction text');
-        $table->add_field('timecreated', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, null, 'Timestamp when the record was created');
-        $table->add_field('timemodified', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, null, 'Timestamp when the record was last modified');
+        $table->add_field(
+            'id',
+            XMLDB_TYPE_INTEGER,
+            '10',
+            null,
+            XMLDB_NOTNULL,
+            XMLDB_SEQUENCE,
+            null,
+            'Standard Moodle primary key'
+        );
+        $table->add_field(
+            'description',
+            XMLDB_TYPE_TEXT,
+            null,
+            null,
+            null,
+            null,
+            null,
+            'Description of the homework literature'
+        );
+        $table->add_field(
+            'startpage',
+            XMLDB_TYPE_INTEGER,
+            '10',
+            null,
+            null,
+            null,
+            null,
+            'Start page number'
+        );
+        $table->add_field(
+            'endpage',
+            XMLDB_TYPE_INTEGER,
+            '10',
+            null,
+            null,
+            null,
+            null,
+            'End page number'
+        );
+        $table->add_field(
+            'introformat',
+            XMLDB_TYPE_INTEGER,
+            '4',
+            null,
+            XMLDB_NOTNULL,
+            null,
+            '0',
+            'Format of the introduction text'
+        );
+        $table->add_field(
+            'timecreated',
+            XMLDB_TYPE_INTEGER,
+            '10',
+            null,
+            XMLDB_NOTNULL,
+            null,
+            null,
+            'Timestamp when the record was created'
+        );
+        $table->add_field(
+            'timemodified',
+            XMLDB_TYPE_INTEGER,
+            '10',
+            null,
+            XMLDB_NOTNULL,
+            null,
+            null,
+            'Timestamp when the record was last modified'
+        );
 
         // Adding keys to table homework_literature.
-        $table->add_key('primary', XMLDB_KEY_PRIMARY, ['id']);
+        $table->add_key(
+            'primary',
+            XMLDB_KEY_PRIMARY,
+            ['id']
+        );
 
         // Conditionally launch create table for homework_literature.
         if (!$dbman->table_exists($table)) {
@@ -72,16 +205,74 @@ function xmldb_homework_upgrade($oldversion) {
         $table = new xmldb_table('homework_links');
 
         // Adding fields to table homework_links.
-        $table->add_field('id', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, XMLDB_SEQUENCE, null);
-        $table->add_field('usermodified', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, '0');
-        $table->add_field('timecreated', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, '0');
-        $table->add_field('timemodified', XMLDB_TYPE_INTEGER, '10', null, XMLDB_NOTNULL, null, '0');
-        $table->add_field('description', XMLDB_TYPE_TEXT, null, null, null, null, null);
-        $table->add_field('link', XMLDB_TYPE_TEXT, null, null, XMLDB_NOTNULL, null, null);
+        $table->add_field(
+            'id',
+            XMLDB_TYPE_INTEGER,
+            '10',
+            null,
+            XMLDB_NOTNULL,
+            XMLDB_SEQUENCE,
+            null
+        );
+        $table->add_field(
+            'usermodified',
+            XMLDB_TYPE_INTEGER,
+            '10',
+            null,
+            XMLDB_NOTNULL,
+            null,
+            '0'
+        );
+        $table->add_field(
+            'timecreated',
+            XMLDB_TYPE_INTEGER,
+            '10',
+            null,
+            XMLDB_NOTNULL,
+            null,
+            '0'
+        );
+        $table->add_field(
+            'timemodified',
+            XMLDB_TYPE_INTEGER,
+            '10',
+            null,
+            XMLDB_NOTNULL,
+            null,
+            '0'
+        );
+        $table->add_field(
+            'description',
+            XMLDB_TYPE_TEXT,
+            null,
+            null,
+            null,
+            null,
+            null
+        );
+        $table->add_field(
+            'link',
+            XMLDB_TYPE_TEXT,
+            null,
+            null,
+            XMLDB_NOTNULL,
+            null,
+            null
+        );
 
         // Adding keys to table homework_links.
-        $table->add_key('primary', XMLDB_KEY_PRIMARY, ['id']);
-        $table->add_key('usermodified', XMLDB_KEY_FOREIGN, ['usermodified'], 'user', ['id']);
+        $table->add_key(
+            'primary',
+            XMLDB_KEY_PRIMARY,
+            ['id']
+        );
+        $table->add_key(
+            'usermodified',
+            XMLDB_KEY_FOREIGN,
+            ['usermodified'],
+            'user',
+            ['id']
+        );
 
         // Conditionally launch create table for homework_links.
         if (!$dbman->table_exists($table)) {
@@ -89,9 +280,9 @@ function xmldb_homework_upgrade($oldversion) {
         }
 
 
-        // homework savepoint reached.
+        // Homework savepoint reached.
         upgrade_mod_savepoint(true, 2024090500, 'homework');
     }
 
     return true;
-}
\ No newline at end of file
+}
diff --git a/server/moodle/mod/homework/lib.php b/server/moodle/mod/homework/lib.php
index faff8b156..880e766cc 100644
--- a/server/moodle/mod/homework/lib.php
+++ b/server/moodle/mod/homework/lib.php
@@ -13,7 +13,6 @@
 //
 // You should have received a copy of the GNU General Public License
 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
-// defined('MOODLE_INTERNAL') || die();
 
 /**
  * lib functions for homework plugin
@@ -41,7 +40,7 @@ function homework_add_instance($homeworkdata) {
     if (!empty($homeworkdata->duedateselector)) {
         $homeworkdata->duedate = $homeworkdata->duedateselector;  // Store the due date as a UNIX timestamp.
     } else {
-        $homeworkdata->duedate = 0;  // If no due date is set, store 0 in the database.
+        $homeworkdata->duedate = null;  // If no due date is set, store null in the database.
     }
 
     $homeworkdata->id = $DB->insert_record('homework', $homeworkdata);
diff --git a/server/moodle/mod/homework/tests/modal_test.php b/server/moodle/mod/homework/tests/modal_test.php
index d1b942358..bab89ca9c 100644
--- a/server/moodle/mod/homework/tests/modal_test.php
+++ b/server/moodle/mod/homework/tests/modal_test.php
@@ -38,6 +38,7 @@ final class modal_test extends advanced_testcase {
      * @return void
      * @throws coding_exception
      * @runInSeparateProcess
+     * @covers :: \mod_homework\external\get_homework_chooser
      */
     public function test_get_homework_chooser(): void {
         global $DB;
diff --git a/server/moodle/mod/homework/tests/save_homework_test.php b/server/moodle/mod/homework/tests/save_homework_test.php
index 8e8f3bc35..521c36e83 100644
--- a/server/moodle/mod/homework/tests/save_homework_test.php
+++ b/server/moodle/mod/homework/tests/save_homework_test.php
@@ -26,6 +26,7 @@
 namespace mod_homework;
 
 use advanced_testcase;
+use dml_exception;
 
 /**
  *
@@ -42,7 +43,8 @@ protected function setUp(): void {
     /**
      * Test saving literature homework with page range.
      * @runInSeparateProcess
-     * @throws \dml_exception
+     * @throws dml_exception
+     * @covers :: \mod_homework\external\save_homework_literature
      */
     public function test_save_homework_literature(): void {
         global $DB;
@@ -73,7 +75,8 @@ public function test_save_homework_literature(): void {
     /**
      * Test saving a homework with a link.
      * @runInSeparateProcess
-     * @throws \dml_exception
+     * @throws dml_exception
+     * @covers :: \mod_homework\external\save_homework_link
      */
     public function test_save_homework_link(): void {
         global $DB;
diff --git a/server/moodle/mod/homework/version.php b/server/moodle/mod/homework/version.php
index 4c69c0cfe..f8d6da733 100644
--- a/server/moodle/mod/homework/version.php
+++ b/server/moodle/mod/homework/version.php
@@ -13,7 +13,6 @@
 //
 // You should have received a copy of the GNU General Public License
 // along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
-global $plugin;
 
 /**
  * Version metadata for the mod_homework plugin.
@@ -22,14 +21,12 @@
  * @copyright 2024, cs-24-sw-5-01 <cs-24-sw-5-01@student.aau.dk>
  * @license   http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
  */
+
 defined('MOODLE_INTERNAL') || die();
+global $plugin;
 
-$plugin->version   = 2024101400;       // The current module version (Date: YYYYMMDDXX).
-$plugin->requires  = 2024090300;    // Requires this Moodle version.
-$plugin->component = 'mod_homework';        // Full name of the plugin (used for diagnostics)
-//$plugin->cron      = 0;
 
-//$plugin->dependencies = [
-  //  'mod_forum' => 2022042100,
-  //  'mod_data' => 2022042100
-//];
\ No newline at end of file
+$plugin->version   = 2024101400;       // The current module version (Date: YYYYMMDDXX).
+$plugin->requires  = 2024090300;       // Requires this Moodle version.
+$plugin->component = 'mod_homework';    // Full name of the plugin (used for diagnostics).
+// $plugin->cron      = 0; // Cron job setting.