.forgejo/workflows/phpunit.yml

@@ -74,6 +74,11 @@ jobs:
         if: steps.cache-wordpress.outputs.cache-hit != 'false'
         run: bash bin/install-wp-tests.sh wordpress_test root root 127.0.0.1 6.6 false true true true
 
+      - name: Run Feature tests of the ActivityPub Event Bridge
+        run: cd /workspace/Event-Federation/wordpress-activitypub-event-bridge/ && ./vendor/bin/phpunit --filter=reminder
+        env:
+          PHP_VERSION: ${{ matrix.php-version }}
+
       - name: Run Integration tests for The Events Calendar
         run: cd /workspace/Event-Federation/wordpress-activitypub-event-bridge/ && ./vendor/bin/phpunit --filter=the_events_calendar
         env:

build/reminder/block.json

@@ -0,0 +1,8 @@
+{
+  "name": "reminder",
+  "title": "Reminder Plugin: not a block, but block.json is very useful.",
+  "category": "widgets",
+  "icon": "admin-comments",
+  "keywords": [],
+  "editorScript": "file:./plugin.js"
+}

build/reminder/plugin.asset.php

@@ -0,0 +1 @@
+<?php return array('dependencies' => array('react-jsx-runtime', 'wp-components', 'wp-core-data', 'wp-data', 'wp-editor', 'wp-i18n', 'wp-plugins'), 'version' => 'd491284dfb7e5078a777');

build/reminder/plugin.js

@@ -0,0 +1 @@
+(()=>{"use strict";const e=window.wp.editor,t=window.wp.plugins,i=window.wp.components,n=window.wp.data,a=window.wp.coreData,r=window.wp.i18n,d=window.ReactJSXRuntime,p=activityPubEventBridge.reminderTypeGap;(0,t.registerPlugin)("activitypub-event-bridge-reminder",{render:()=>{const t=(0,n.useSelect)((e=>e("core/editor").getCurrentPostType()),[]),[_,b]=(0,a.useEntityProp)("postType",t,"meta"),u=_?.activitypub_event_bridge_reminder_time_gap?_?.activitypub_event_bridge_reminder_time_gap:p;return(0,d.jsx)(e.PluginDocumentSettingPanel,{name:"activitypub",title:(0,r.__)("Send reminder before event's start","activitypub"),children:(0,d.jsx)(i.SelectControl,{label:(0,r.__)("Time gap","activitypub"),value:u,options:[{label:(0,r.__)("Disabled","activitypub-event-bridge"),value:0},{label:(0,r.__)("6 hours","activitypub-event-bridge"),value:21600},{label:(0,r.__)("1 day","activitypub-event-bridge"),value:86400},{label:(0,r.__)("3 days","activitypub-event-bridge"),value:259200},{label:(0,r.__)("1 week","activitypub-event-bridge"),value:604800}],onChange:e=>{b({..._,activitypub_event_bridge_reminder_time_gap:e})},__nextHasNoMarginBottom:!0})})}})})();

composer.json

@@ -57,8 +57,9 @@
         ],
         "test-debug": [
             "@prepare-test",
-            "@test-eventin"
+            "@test-wp-event-manager"
         ],
+        "test-features": "phpunit --filter=reminder",
         "test-vs-event-list": "phpunit --filter=vs_event_list",
         "test-the-events-calendar": "phpunit --filter=the_events_calendar",
         "test-gatherpress": "phpunit --filter=gatherpress",

includes/activitypub/transformer/class-event.php

@@ -11,6 +11,7 @@ namespace ActivityPub_Event_Bridge\Activitypub\Transformer;
 // Exit if accessed directly.
 defined( 'ABSPATH' ) || exit; // @codeCoverageIgnore
 
+use Activitypub\Activity\Activity;
 use Activitypub\Activity\Extended_Object\Event as Event_Object;
 use Activitypub\Activity\Extended_Object\Place;
 use Activitypub\Transformer\Post;
@@ -148,7 +149,7 @@ abstract class Event extends Post {
 	 *
 	 * This is mandatory and must be implemented in the final event transformer class.
 	 */
-	abstract protected function get_start_time(): string;
+	abstract public function get_start_time(): string;
 
 	/**
 	 * Get the end time.
@@ -376,4 +377,19 @@ abstract class Event extends Post {
 
 		return $activitypub_object;
 	}
+
+	/**
+	 * Creates an activity for announcing itself.
+	 *
+	 * @return Activity The Activity.
+	 */
+	public function to_announce_self_activity() {
+		$activity = new Activity();
+		$activity->set_type( 'Announce' );
+
+		// Pre-fill the Activity with data (for example cc and to).
+		$activity->set_object( $this->get_id() );
+
+		return $activity;
+	}
 }

includes/activitypub/transformer/class-gatherpress.php

@@ -80,7 +80,7 @@ final class GatherPress extends Event {
 	/**
 	 * Get the end time from the event object.
 	 */
-	protected function get_start_time(): string {
+	public function get_start_time(): string {
 		return $this->gp_event->get_datetime_start( 'Y-m-d\TH:i:s\Z' );
 	}
 

includes/activitypub/transformer/class-the-events-calendar.php

@@ -83,7 +83,7 @@ final class The_Events_Calendar extends Event {
 	/**
 	 * Get the end time from the event object.
 	 */
-	protected function get_start_time(): string {
+	public function get_start_time(): string {
 		$date = date_create( $this->tribe_event->start_date, wp_timezone() );
 		return \gmdate( 'Y-m-d\TH:i:s\Z', $date->getTimestamp() );
 	}

includes/activitypub/transformer/class-vs-event-list.php

@@ -58,7 +58,7 @@ final class VS_Event_List extends Event_Transformer {
 	/**
 	 * Get the end time from the events metadata.
 	 */
-	protected function get_start_time(): string {
+	public function get_start_time(): string {
 		$start_time = get_post_meta( $this->wp_object->ID, 'event-start-date', true );
 		return \gmdate( 'Y-m-d\TH:i:s\Z', $start_time );
 	}

includes/class-reminder.php

@@ -0,0 +1,194 @@
+<?php
+/**
+ * General settings class.
+ *
+ * This file contains the General class definition, which handles the "General" settings
+ * page for the ActivityPub Event Extension Plugin, providing options for configuring various general settings.
+ *
+ * @package ActivityPub_Event_Bridge
+ * @since 1.0.0
+ */
+
+namespace ActivityPub_Event_Bridge;
+
+// Exit if accessed directly.
+defined( 'ABSPATH' ) || exit; // @codeCoverageIgnore
+
+use Activitypub\Activity_Dispatcher;
+use Activitypub\Transformer\Factory as Transformer_Factory;
+use ActivityPub_Event_Bridge\Setup;
+use ActivityPub_Event_Bridge\Activitypub\Transformer\Event as Event_Transformer;
+use DateTime;
+
+use function Activitypub\is_user_disabled;
+
+/**
+ * Adds automatic announcing or sending of reminders before the events start time.
+ */
+class Reminder {
+	/**
+	 * Initialize the class, registering WordPress hooks.
+	 */
+	public static function init() {
+		// Post transitions.
+		\add_action( 'transition_post_status', array( self::class, 'maybe_schedule_event_reminder' ), 33, 3 );
+		\add_action( 'delete_post', array( self::class, 'unschedule_event_reminder' ), 33, 1 );
+
+		// Send an event reminder.
+		\add_action( 'activitypub_event_bridge_send_event_reminder', array( self::class, 'send_event_reminder' ), 10, 1 );
+
+		// Load the block which allows overriding the reminder time for an individual event in the post settings.
+		\add_action( 'enqueue_block_editor_assets', array( self::class, 'enqueue_editor_assets' ) );
+
+		// Register the post-meta which stores per-event overrides of the side-wide default of the reminder time gap.
+		\add_action( 'init', array( self::class, 'register_postmeta' ), 11 );
+	}
+
+	/**
+	 * Register post meta for controlling whether and when a reminder is scheduled for an individual event.
+	 */
+	public static function register_postmeta() {
+		$ap_post_types = \get_post_types_by_support( 'activitypub' );
+		foreach ( $ap_post_types as $post_type ) {
+			\register_post_meta(
+				$post_type,
+				'activitypub_event_bridge_reminder_time_gap',
+				array(
+					'show_in_rest'      => true,
+					'single'            => true,
+					'type'              => 'integer',
+					'sanitize_callback' => 'absint',
+				)
+			);
+		}
+	}
+
+	/**
+	 * Enqueue the block editor assets.
+	 */
+	public static function enqueue_editor_assets() {
+		// Check for our supported post types.
+		$current_screen   = \get_current_screen();
+		$event_post_types = Setup::get_instance()->get_active_event_plugins_post_types();
+		if ( ! $current_screen || ! in_array( $current_screen->post_type, $event_post_types, true ) ) {
+			return;
+		}
+		$asset_data = include ACTIVITYPUB_EVENT_BRIDGE_PLUGIN_DIR . 'build/reminder/plugin.asset.php';
+		$plugin_url = plugins_url( 'build/reminder/plugin.js', ACTIVITYPUB_EVENT_BRIDGE_PLUGIN_FILE );
+		wp_enqueue_script( 'activitypub-event-bridge-reminder', $plugin_url, $asset_data['dependencies'], $asset_data['version'], true );
+
+		// Pass the the default site wide time gap option to the settings block on the events edit page.
+		wp_localize_script(
+			'activitypub-event-bridge-reminder',
+			'activityPubEventBridge',
+			array(
+				'reminderTypeGap' => \get_option( 'activitypub_event_bridge_reminder_time_gap', 0 ),
+			)
+		);
+	}
+
+	/**
+	 * Schedule Activities.
+	 *
+	 * @param string  $new_status  New post status.
+	 * @param string  $old_status  Old post status.
+	 * @param WP_Post $post        Post object.
+	 */
+	public static function maybe_schedule_event_reminder( $new_status, $old_status, $post ): void {
+		// Re-Check that we got a valid post.
+		$post = get_post( $post );
+
+		if ( ! $post ) {
+			return;
+		}
+
+		// At first always unschedule the reminder for this event, it will be added again, in case.
+		self::unschedule_event_reminder( $post->ID );
+
+		// Do not set reminders if post is password protected.
+		if ( \post_password_required( $post ) ) {
+			return;
+		}
+
+		// Only schedule an reminder for event post types.
+		if ( ! Setup::get_instance()->is_post_type_event_of_active_event_plugin( $post->post_type ) ) {
+			return;
+		}
+
+		// Do not schedule a reminder if the event is not published.
+		if ( 'publish' !== $new_status ) {
+			return;
+		}
+
+		// See if a reminder time gap is set for the event individually in the events post-meta.
+		$reminder_time_gap = (int) get_post_meta( $post->ID, 'activitypub_event_bridge_reminder_time_gap', true );
+
+		// If not fallback to the global reminder time gap.
+		if ( ! $reminder_time_gap ) {
+			$reminder_time_gap = \get_option( 'activitypub_event_bridge_reminder_time_gap', 0 );
+		}
+
+		// Any non positive integer means that this feature is not active for this event post.
+		if ( 0 === $reminder_time_gap || ! is_int( $reminder_time_gap ) ) {
+			return;
+		}
+
+		// Get start time of the event.
+		$event_transformer = Transformer_Factory::get_transformer( $post );
+
+		if ( \is_wp_error( $event_transformer ) || ! $event_transformer instanceof Event_Transformer ) {
+			return;
+		}
+
+		$start_time      = $event_transformer->get_start_time();
+		$start_datetime  = new DateTime( $start_time );
+		$start_timestamp = $start_datetime->getTimestamp();
+
+		// Get the time when the reminder of the event's start should be sent.
+		$schedule_time = $start_timestamp - $reminder_time_gap;
+
+		// If the reminder time has already passed "now" skip it.
+		if ( $schedule_time < \time() ) {
+			return;
+		}
+
+		// All checks passed: schedule a single event which will trigger the sending of the reminder for this event post.
+		\wp_schedule_single_event( $schedule_time, 'activitypub_event_bridge_send_event_reminder', array( $post->ID ) );
+	}
+
+	/**
+	 * Unschedule the event reminder.
+	 *
+	 * @param int $post_id The WordPress post ID of the event post.
+	 */
+	public static function unschedule_event_reminder( $post_id ): void {
+		\wp_clear_scheduled_hook( 'activitypub_event_bridge_send_event_reminder', array( $post_id ) );
+	}
+
+	/**
+	 * Send a reminder for an event post.
+	 *
+	 * This currently sends an Announce activity.
+	 *
+	 * @param int $post_id The WordPress post ID of the event post.
+	 */
+	public static function send_event_reminder( $post_id ): void {
+		$post = \get_post( $post_id );
+
+		$transformer = Transformer_Factory::get_transformer( $post );
+
+		if ( \is_wp_error( $transformer ) || ! $transformer instanceof Event_Transformer ) {
+			return;
+		}
+
+		$user_id = $transformer->get_wp_user_id();
+
+		if ( $user_id > 0 && is_user_disabled( $user_id ) ) {
+			return;
+		}
+
+		$activity = $transformer->to_announce_self_activity( 'Announce' );
+
+		Activity_Dispatcher::send_activity_to_followers( $activity, $user_id, $post );
+	}
+}

includes/class-settings.php

@@ -44,7 +44,7 @@ class Settings {
 			'activitypub_event_bridge_default_event_category',
 			array(
 				'type'              => 'string',
-				'description'       => \__( 'Define your own custom post template', 'activitypub' ),
+				'description'       => \__( 'Default standardized federated event category.s', 'activitypub' ),
 				'show_in_rest'      => true,
 				'default'           => self::DEFAULT_EVENT_CATEGORY,
 				'sanitize_callback' => array( self::class, 'sanitize_mapped_event_category' ),
@@ -56,11 +56,22 @@ class Settings {
 			'activitypub_event_bridge_event_category_mappings',
 			array(
 				'type'              => 'array',
-				'description'       => \__( 'Define your own custom post template', 'activitypub' ),
+				'description'       => \__( 'Category mappings to standardized federated event categories.', 'activitypub' ),
 				'default'           => array(),
 				'sanitize_callback' => array( self::class, 'sanitize_event_category_mappings' ),
 			)
 		);
+
+		\register_setting(
+			'activitypub-event-bridge',
+			'activitypub_event_bridge_reminder_time_gap',
+			array(
+				'type'              => 'array',
+				'description'       => \__( 'Time gap in seconds when a reminder is triggered that the event is about to start.', 'activitypub' ),
+				'default'           => 0, // Zero leads to this feature being deactivated.
+				'sanitize_callback' => 'absint',
+			)
+		);
 	}
 
 	/**

includes/class-setup.php

@@ -18,6 +18,7 @@ defined( 'ABSPATH' ) || exit; // @codeCoverageIgnore
 use ActivityPub_Event_Bridge\Admin\Event_Plugin_Admin_Notices;
 use ActivityPub_Event_Bridge\Admin\General_Admin_Notices;
 use ActivityPub_Event_Bridge\Admin\Settings_Page;
+use ActivityPub_Event_Bridge\Reminder;
 use ActivityPub_Event_Bridge\Plugins\Event_Plugin;
 
 require_once ABSPATH . 'wp-admin/includes/plugin.php';
@@ -118,6 +119,38 @@ class Setup {
 		return $this->active_event_plugins;
 	}
 
+	/**
+	 * Getter function for the active event plugins post types.
+	 *
+	 * @return array List of event post types of the active event plugins.
+	 */
+	public function get_active_event_plugins_post_types() {
+		$post_types = array();
+		foreach ( $this->active_event_plugins as $event_plugin ) {
+			$post_types[] = $event_plugin->get_post_type();
+		}
+
+		return $post_types;
+	}
+
+	/**
+	 * Function to check whether a post type is an event post type of an active event plugin.
+	 *
+	 * @param string $post_type The post type.
+	 *
+	 * @return bool True if it is an event post type.
+	 */
+	public function is_post_type_event_of_active_event_plugin( $post_type ) {
+		foreach ( $this->active_event_plugins as $event_plugin ) {
+			if ( $post_type === $event_plugin->get_post_type() ) {
+				return true;
+			}
+		}
+
+		return false;
+	}
+
+
 	/**
 	 * Holds all the classes for the supported event plugins.
 	 *
@@ -186,6 +219,8 @@ class Setup {
 			return;
 		}
 
+		add_action( 'init', array( Reminder::class, 'init' ) );
+
 		add_filter( 'activitypub_transformer', array( $this, 'register_activitypub_event_transformer' ), 10, 3 );
 	}
 

includes/plugins/class-event-plugin.php

@@ -69,6 +69,8 @@ abstract class Event_Plugin {
 
 	/**
 	 * Returns the Activitypub transformer for the event plugins event post type.
+	 *
+	 * @return string
 	 */
 	public static function get_activitypub_event_transformer_class(): string {
 		return str_replace( 'Plugins', 'Activitypub\Transformer', static::class );

package.json

@@ -0,0 +1,19 @@
+
+{
+  "name": "activitypub-poll",
+  "version": "0.1.0",
+  "author": {
+    "name": "André Menrath",
+    "web": "https://graz.social/@linos"
+  },
+  "scripts": {
+    "dev": "wp-scripts start",
+    "build": "wp-scripts build",
+    "readme": "grunt wp_readme_to_markdown"
+  },
+ "devDependencies": {
+		"@wordpress/scripts": "^30.0.2",
+    "grunt-wp-readme-to-markdown": "^2.0.1",
+    "classnames": "^2.3.2"
+ }
+}

phpcs.xml

@@ -26,6 +26,12 @@
 	<!-- Exclude the Node Modules directory. -->
 	<exclude-pattern>/node_modules/*</exclude-pattern>
 
+	<!-- Exclude Javascript files. -->
+	<exclude-pattern>*.js</exclude-pattern>
+
+	<!-- Exclude build assets from js blocks. -->
+	<exclude-pattern>/build/*/*asset.php</exclude-pattern>
+
 	<!-- Exclude minified Javascript files. -->
 	<exclude-pattern>*.min.js</exclude-pattern>
 

src/reminder/block.json

@@ -0,0 +1,9 @@
+{
+	"name": "reminder",
+	"title": "Reminder Plugin: not a block, but block.json is very useful.",
+	"category": "widgets",
+	"icon": "admin-comments",
+	"keywords": [
+	],
+	"editorScript": "file:./plugin.js"
+}

src/reminder/plugin.js

@@ -0,0 +1,43 @@
+import { PluginDocumentSettingPanel } from '@wordpress/editor';
+import { registerPlugin } from '@wordpress/plugins';
+import { SelectControl } from '@wordpress/components';
+import { useSelect } from '@wordpress/data';
+import { useEntityProp } from '@wordpress/core-data';
+import { __ } from '@wordpress/i18n';
+
+const reminderTimeGapDefault = activityPubEventBridge.reminderTypeGap;
+
+const Reminder = () => {
+	const postType = useSelect(
+		( select ) => select( 'core/editor' ).getCurrentPostType(),
+		[]
+	);
+	const [ meta, setMeta ] = useEntityProp( 'postType', postType, 'meta' );
+
+	const reminderTimeGap = meta?.activitypub_event_bridge_reminder_time_gap ? meta?.activitypub_event_bridge_reminder_time_gap : reminderTimeGapDefault;
+
+	return (
+		<PluginDocumentSettingPanel
+			name="activitypub"
+			title={ __( 'Send reminder before event\'s start', 'activitypub' ) }
+		>
+			<SelectControl
+				label={ __( 'Time gap', 'activitypub' ) }
+				value={ reminderTimeGap }
+				options={ [
+					{ label: __( 'Disabled', 'activitypub-event-bridge' ), value: 0 },
+					{ label: __( '6 hours', 'activitypub-event-bridge' ), value: 21600 },
+					{ label: __( '1 day', 'activitypub-event-bridge' ), value: 86400 },
+					{ label: __( '3 days', 'activitypub-event-bridge' ), value: 259200 },
+					{ label: __( '1 week', 'activitypub-event-bridge' ), value: 604800 }
+				] }
+				onChange={ ( value ) => {
+					setMeta( { ...meta, activitypub_event_bridge_reminder_time_gap: value } );
+				} }
+				__nextHasNoMarginBottom
+			/>
+		</PluginDocumentSettingPanel>
+	);
+}
+
+registerPlugin( 'activitypub-event-bridge-reminder', { render: Reminder } );

templates/settings.php

@@ -29,6 +29,15 @@ require_once ACTIVITYPUB_EVENT_BRIDGE_PLUGIN_DIR . '/includes/event-categories.p
 
 $selected_default_event_category = \get_option( 'activitypub_event_bridge_default_event_category', 'MEETING' );
 $current_category_mapping        = \get_option( 'activitypub_event_bridge_event_category_mappings', array() );
+$reminder_time_gap               = \get_option( 'activitypub_event_bridge_reminder_time_gap', 0 );
+
+$reminder_time_gap_choices = array(
+	0                   => __( 'Disabled', 'activitypub-event-bridge' ),
+	HOUR_IN_SECONDS * 6 => __( '6 hours', 'activitypub-event-bridge' ),
+	DAY_IN_SECONDS      => __( '1 day', 'activitypub-event-bridge' ),
+	DAY_IN_SECONDS * 3  => __( '3 days', 'activitypub-event-bridge' ),
+	WEEK_IN_SECONDS     => __( '1 week', 'activitypub-event-bridge' ),
+)
 ?>
 
 <div class="activitypub-settings-header">
@@ -98,6 +107,17 @@ $current_category_mapping        = \get_option( 'activitypub_event_bridge_event_
 			</table>
 		</div>
 		<?php endif; ?>
+		<div class="box">
+			<h2> <?php esc_html_e( 'Send reminder before event', 'activitypub-event-bridge' ); ?> </h2>
+			<p> <?php esc_html_e( 'Specify a time interval before the event starts to trigger a reminder. This reminder automatically boosts the event, making it reappear in users\' timelines at the defined time before the event to increase visibility just before the event begins.', 'activitypub-event-bridge' ); ?> </p>
+			<select id="activitypub_event_bridge_reminder_time_gap" name="activitypub_event_bridge_reminder_time_gap">';
+						<?php
+						foreach ( $reminder_time_gap_choices as $value => $label ) {
+							echo '<option value="' . esc_attr( $value ) . '" ' . selected( $reminder_time_gap, $value, false ) . '>' . esc_html( $label ) . '</option>';
+						}
+						?>
+			</select>
+		</div>
 		<?php \submit_button(); ?>
 	</form>
 </div>

tests/bootstrap.php

@@ -50,9 +50,6 @@ function _manually_load_plugin() {
 	$plugin_file = null;
 	// See if we want to run integration tests for a specific event-plugin.
 	switch ( $activitypub_event_extension_integration_filter ) {
-		case 'the_events_calendar':
-			$plugin_file = 'the-events-calendar/the-events-calendar.php';
-			break;
 		case 'vs_event_list':
 			$plugin_file = 'very-simple-event-list/vsel.php';
 			break;
@@ -68,6 +65,9 @@ function _manually_load_plugin() {
 		case 'wp_event_manager':
 			$plugin_file = 'wp-event-manager/wp-event-manager.php';
 			break;
+		default:
+			// By default we test other stuff using The Events Calendar.
+			$plugin_file = 'the-events-calendar/the-events-calendar.php';
 	}
 
 	if ( $plugin_file ) {

tests/test-class-plugin-events-manger.php

@@ -16,7 +16,7 @@ class Test_Events_Manager extends WP_UnitTestCase {
 		parent::set_up();
 
 		if ( ! class_exists( 'EM_Events' ) ) {
-			self::markTestSkipped( 'VS Event List plugin is not active.' );
+			self::markTestSkipped( 'Events Manager plugin is not active.' );
 		}
 
 		// For tests allow every user to create new events.

tests/test-class-plugin-gatherpress.php

@@ -1,12 +1,12 @@
 <?php
 /**
- * Class SampleTest
+ * Tests for GatherPress.
  *
  * @package ActivityPub_Event_Bridge
  */
 
 /**
- * Sample test case.
+ * Test class for testing the GatherPress integration.
  */
 class Test_GatherPress extends WP_UnitTestCase {
 	/**

tests/test-class-reminder.php

@@ -0,0 +1,183 @@
+<?php
+/**
+ * Test for Reminder class.
+ *
+ * @package ActivityPub_Event_Bridge
+ */
+
+/**
+ * Test class for testing the scheduling of reminder Activities.
+ */
+class Test_Reminder extends WP_UnitTestCase {
+	/**
+	 * Mockup events of certain complexity.
+	 */
+	public const MOCKUP_VENUE = array(
+		'venue'  => 'Minimal Venue',
+		'status' => 'publish',
+	);
+
+	public const MOCKUP_EVENT = array(
+		'title'      => 'My Event',
+		'content'    => 'Come to my event!',
+		'start_date' => '+10 days 15:00:00',
+		'duration'   => HOUR_IN_SECONDS,
+		'status'     => 'publish',
+	);
+
+	/**
+	 * Override the setup function, so that tests don't run if the Events Calendar is not active.
+	 */
+	public function set_up() {
+		parent::set_up();
+
+		if ( ! class_exists( '\Tribe__Events__Main' ) ) {
+			self::markTestSkipped( 'The Events Calendar is not active.' );
+		}
+
+		// For tests allow every user to create new events.
+		update_option( 'dbem_events_anonymous_submissions', true );
+
+		// Make sure that ActivityPub support is enabled for Events Manager.
+		$aec = \ActivityPub_Event_Bridge\Setup::get_instance();
+		$aec->activate_activitypub_support_for_active_event_plugins();
+
+		// Delete all posts afterwards.
+		_delete_all_posts();
+	}
+
+	/**
+	 * Test that with the default reminder setting (time-gap is zero) no reminder event is scheduled.
+	 */
+	public function test_event_reminder_not_being_scheduled_by_default() {
+		// Create a The Events Calendar Event.
+		$wp_object = tribe_events()
+			->set_args( self::MOCKUP_EVENT )
+			->create();
+
+		$scheduled_event = \wp_get_scheduled_event( 'activitypub_event_bridge_send_event_reminder', array( $wp_object->ID ) );
+
+		$this->assertEquals( false, $scheduled_event );
+	}
+
+	/**
+	 * Test that with a side-wide option the reminder is scheduled.
+	 */
+	public function test_event_reminder_scheduled_with_site_wide_option() {
+		\update_option( 'activitypub_event_bridge_reminder_time_gap', DAY_IN_SECONDS );
+		// Create a The Events Calendar Event.
+		$wp_object = tribe_events()
+			->set_args( self::MOCKUP_EVENT )
+			->create();
+
+		$scheduled_event = \wp_get_scheduled_event( 'activitypub_event_bridge_send_event_reminder', array( $wp_object->ID ) );
+
+		$this->assertNotEquals( false, $scheduled_event );
+		$this->assertEquals( strtotime( self::MOCKUP_EVENT['start_date'] ) - DAY_IN_SECONDS, $scheduled_event->timestamp );
+		$this->assertEquals( false, $scheduled_event->schedule );
+		$this->assertEquals( 'activitypub_event_bridge_send_event_reminder', $scheduled_event->hook );
+	}
+
+	/**
+	 * Test that a specific event can override the side-wide reminder default.
+	 */
+	public function test_event_reminder_scheduled_with_per_event_override() {
+		\update_option( 'activitypub_event_bridge_reminder_time_gap', DAY_IN_SECONDS );
+
+		// Create a The Events Calendar Event.
+		$wp_object = tribe_events()
+			->set_args(
+				array_merge(
+					self::MOCKUP_EVENT,
+					array( 'activitypub_event_bridge_reminder_time_gap' => DAY_IN_SECONDS * 3 ),
+				)
+			)
+			->create();
+
+		$scheduled_event = \wp_get_scheduled_event( 'activitypub_event_bridge_send_event_reminder', array( $wp_object->ID ) );
+
+		$this->assertNotEquals( false, $scheduled_event );
+		$this->assertEquals( strtotime( self::MOCKUP_EVENT['start_date'] ) - DAY_IN_SECONDS * 3, $scheduled_event->timestamp );
+		$this->assertEquals( false, $scheduled_event->schedule );
+		$this->assertEquals( 'activitypub_event_bridge_send_event_reminder', $scheduled_event->hook );
+
+		// Now update the option once more to see if the schedule got updated too.
+		$post_id = array_key_first(
+			tribe_events( $wp_object->ID )
+				->set_args(
+					array( 'activitypub_event_bridge_reminder_time_gap' => HOUR_IN_SECONDS ),
+				)
+				->save()
+		);
+
+		$scheduled_event = \wp_get_scheduled_event( 'activitypub_event_bridge_send_event_reminder', array( $post_id ) );
+		$this->assertNotEquals( false, $scheduled_event );
+		$this->assertEquals( strtotime( self::MOCKUP_EVENT['start_date'] ) - HOUR_IN_SECONDS, $scheduled_event->timestamp );
+	}
+
+	/**
+	 * Test that the scheduled reminder is removed when the event is deleted.
+	 */
+	public function test_event_reminder_deleted_event() {
+		\update_option( 'activitypub_event_bridge_reminder_time_gap', DAY_IN_SECONDS );
+
+		// Create a The Events Calendar Event.
+		$wp_object = tribe_events()
+			->set_args(
+				array_merge(
+					self::MOCKUP_EVENT,
+					array( 'activitypub_event_bridge_reminder_time_gap' => DAY_IN_SECONDS * 3 ),
+				)
+			)
+			->create();
+
+		$scheduled_event = \wp_get_scheduled_event( 'activitypub_event_bridge_send_event_reminder', array( $wp_object->ID ) );
+
+		$this->assertNotEquals( false, $scheduled_event );
+		$this->assertEquals( strtotime( self::MOCKUP_EVENT['start_date'] ) - DAY_IN_SECONDS * 3, $scheduled_event->timestamp );
+		$this->assertEquals( false, $scheduled_event->schedule );
+		$this->assertEquals( 'activitypub_event_bridge_send_event_reminder', $scheduled_event->hook );
+
+		// Now delete the event.
+		tribe_events( $wp_object->ID )->delete();
+
+		$scheduled_event = \wp_get_scheduled_event( 'activitypub_event_bridge_send_event_reminder', array( $wp_object->ID ) );
+		$this->assertEquals( false, $scheduled_event );
+	}
+
+	/**
+	 * Test that the scheduled reminder is removed when the event is moved to trash.
+	 */
+	public function test_event_reminder_event_moved_to_trash() {
+		\update_option( 'activitypub_event_bridge_reminder_time_gap', DAY_IN_SECONDS );
+
+		// Create a The Events Calendar Event.
+		$wp_object = tribe_events()
+			->set_args(
+				array_merge(
+					self::MOCKUP_EVENT,
+					array( 'activitypub_event_bridge_reminder_time_gap' => DAY_IN_SECONDS * 3 ),
+				)
+			)
+			->create();
+
+		$scheduled_event = \wp_get_scheduled_event( 'activitypub_event_bridge_send_event_reminder', array( $wp_object->ID ) );
+
+		$this->assertNotEquals( false, $scheduled_event );
+		$this->assertEquals( strtotime( self::MOCKUP_EVENT['start_date'] ) - DAY_IN_SECONDS * 3, $scheduled_event->timestamp );
+		$this->assertEquals( false, $scheduled_event->schedule );
+		$this->assertEquals( 'activitypub_event_bridge_send_event_reminder', $scheduled_event->hook );
+
+		// Now move the event to the trash.
+		$post_id = array_key_first(
+			tribe_events( $wp_object->ID )
+				->set_args(
+					array( 'post_status' => 'trash' ),
+				)
+				->save()
+		);
+
+		$scheduled_event = \wp_get_scheduled_event( 'activitypub_event_bridge_send_event_reminder', array( $wp_object->ID ) );
+		$this->assertEquals( false, $scheduled_event );
+	}
+}