Implementing the unified functions for custom events with types

src/lib/components/MaintenancePopup.js

@@ -4,6 +4,12 @@ import {BaseComponent} from "$lib/components/base/BaseComponent.js";
 import {getComponent} from "$lib/components/base/ComponentUtils.js";
 import ScrapedAPI from "$lib/booru/scraped/ScrapedAPI.js";
 import {tagsBlacklist} from "$config/tags.ts";
+import {emitterAt} from "$lib/components/events/comms";
+import {
+  eventActiveProfileChanged,
+  eventMaintenanceStateChanged,
+  eventTagsUpdated
+} from "$lib/components/events/maintenance-popup-events";
 
 class BlackListedTagsEncounteredError extends Error {
   /**
@@ -45,6 +51,8 @@ export class MaintenancePopup extends BaseComponent {
   /** @type {number|null} */
   #tagsSubmissionTimer = null;
 
+  #emitter = emitterAt(this);
+
   /**
    * @protected
    */
@@ -95,7 +103,8 @@ export class MaintenancePopup extends BaseComponent {
     this.#activeProfile = activeProfile;
     this.container.classList.toggle('is-active', activeProfile !== null);
     this.#refreshTagsList();
-    this.emit('active-profile-changed', activeProfile);
+
+    this.#emitter.emit(eventActiveProfileChanged, activeProfile);
   }
 
   #refreshTagsList() {
@@ -181,7 +190,7 @@ export class MaintenancePopup extends BaseComponent {
       }
 
       this.#isPlanningToSubmit = true;
-      this.emit('maintenance-state-change', 'waiting');
+      this.#emitter.emit(eventMaintenanceStateChanged, 'waiting');
     }
   }
 
@@ -208,7 +217,7 @@ export class MaintenancePopup extends BaseComponent {
     this.#isPlanningToSubmit = false;
     this.#isSubmitting = true;
 
-    this.emit('maintenance-state-change', 'processing');
+    this.#emitter.emit(eventMaintenanceStateChanged, 'processing');
 
     let maybeTagsAndAliasesAfterUpdate;
 
@@ -249,17 +258,18 @@ export class MaintenancePopup extends BaseComponent {
       }
 
       MaintenancePopup.#notifyAboutPendingSubmission(false);
-      this.emit('maintenance-state-change', 'failed');
+
+      this.#emitter.emit(eventMaintenanceStateChanged, 'failed');
       this.#isSubmitting = false;
 
       return;
     }
 
     if (maybeTagsAndAliasesAfterUpdate) {
-      this.emit('tags-updated', maybeTagsAndAliasesAfterUpdate);
+      this.#emitter.emit(eventTagsUpdated, maybeTagsAndAliasesAfterUpdate);
     }
 
-    this.emit('maintenance-state-change', 'complete');
+    this.#emitter.emit(eventMaintenanceStateChanged, 'complete');
 
     this.#tagsToAdd.clear();
     this.#tagsToRemove.clear();

src/lib/components/MaintenanceStatusIcon.js

@@ -1,5 +1,7 @@
 import {BaseComponent} from "$lib/components/base/BaseComponent.js";
 import {getComponent} from "$lib/components/base/ComponentUtils.js";
+import {on} from "$lib/components/events/comms";
+import {eventMaintenanceStateChanged} from "$lib/components/events/maintenance-popup-events";
 
 export class MaintenanceStatusIcon extends BaseComponent {
   /** @type {import('MediaBoxTools.js').MediaBoxTools} */
@@ -16,7 +18,7 @@ export class MaintenanceStatusIcon extends BaseComponent {
       throw new Error('Status icon element initialized outside of the media box!');
     }
 
-    this.#mediaBoxTools.on('maintenance-state-change', this.#onMaintenanceStateChanged.bind(this));
+    on(this.#mediaBoxTools, eventMaintenanceStateChanged, this.#onMaintenanceStateChanged.bind(this));
   }
 
   /**

src/lib/components/MediaBoxTools.js

@@ -1,6 +1,8 @@
 import {BaseComponent} from "$lib/components/base/BaseComponent.js";
 import {getComponent} from "$lib/components/base/ComponentUtils.js";
 import {MaintenancePopup} from "$lib/components/MaintenancePopup.js";
+import {on} from "$lib/components/events/comms";
+import {eventActiveProfileChanged} from "$lib/components/events/maintenance-popup-events";
 
 export class MediaBoxTools extends BaseComponent {
   /** @type {import('MediaBoxWrapper.js').MediaBoxWrapper|null} */
@@ -34,11 +36,11 @@ export class MediaBoxTools extends BaseComponent {
       }
     }
 
-    this.on('active-profile-changed', this.#onActiveProfileChanged.bind(this));
+    on(this, eventActiveProfileChanged, this.#onActiveProfileChanged.bind(this));
   }
 
   /**
-   * @param {CustomEvent<MaintenanceProfile|null>} profileChangedEvent
+   * @param {CustomEvent<import('$entities/MaintenanceProfile.js').default|null>} profileChangedEvent
    */
   #onActiveProfileChanged(profileChangedEvent) {
     this.container.classList.toggle('has-active-profile', profileChangedEvent.detail !== null);
@@ -61,7 +63,7 @@ export class MediaBoxTools extends BaseComponent {
 
 /**
  * Create a maintenance popup element.
- * @param {HTMLElement} childrenElements List of children elements to append to the component.
+ * @param {HTMLElement[]} childrenElements List of children elements to append to the component.
  * @return {HTMLElement} The maintenance popup element.
  */
 export function createMediaBoxTools(...childrenElements) {

src/lib/components/MediaBoxWrapper.js

@@ -1,6 +1,8 @@
 import {BaseComponent} from "$lib/components/base/BaseComponent.js";
 import {getComponent} from "$lib/components/base/ComponentUtils.js";
 import {buildTagsAndAliasesMap} from "$lib/booru/TagsUtils.js";
+import {on} from "$lib/components/events/comms";
+import {eventTagsUpdated} from "$lib/components/events/maintenance-popup-events";
 
 export class MediaBoxWrapper extends BaseComponent {
   #thumbnailContainer = null;
@@ -13,11 +15,11 @@ export class MediaBoxWrapper extends BaseComponent {
     this.#thumbnailContainer = this.container.querySelector('.image-container');
     this.#imageLinkElement = this.#thumbnailContainer.querySelector('a');
 
-    this.on('tags-updated', this.#onTagsUpdatedRefreshTagsAndAliases.bind(this));
+    on(this, eventTagsUpdated, this.#onTagsUpdatedRefreshTagsAndAliases.bind(this));
   }
 
   /**
-   * @param {CustomEvent<Map<string,string>>} tagsUpdatedEvent
+   * @param {CustomEvent<Map<string,string>|null>} tagsUpdatedEvent
    */
   #onTagsUpdatedRefreshTagsAndAliases(tagsUpdatedEvent) {
     const updatedMap = tagsUpdatedEvent.detail;

src/lib/components/events/comms.ts

@@ -0,0 +1,92 @@
+import type {MaintenancePopupEventsMap} from "$lib/components/events/maintenance-popup-events.ts";
+import {BaseComponent} from "$lib/components/base/BaseComponent";
+
+interface EventsMapping extends MaintenancePopupEventsMap {
+}
+
+type EventCallback<EventDetails> = (event: CustomEvent<EventDetails>) => void;
+type UnsubscribeFunction = () => void;
+type ResolvableTarget = EventTarget | BaseComponent;
+
+function resolveTarget(componentOrElement: ResolvableTarget): EventTarget {
+  if (componentOrElement instanceof BaseComponent) {
+    return componentOrElement.container;
+  }
+
+  return componentOrElement;
+}
+
+export function emit<Event extends keyof EventsMapping>(
+  targetOrComponent: ResolvableTarget,
+  event: Event,
+  details: EventsMapping[Event]
+) {
+  const target = resolveTarget(targetOrComponent);
+
+  target.dispatchEvent(
+    new CustomEvent(event, {
+      detail: details,
+      bubbles: true
+    })
+  );
+}
+
+export function on<Event extends keyof EventsMapping>(
+  targetOrComponent: ResolvableTarget,
+  eventName: Event,
+  callback: EventCallback<EventsMapping[Event]>,
+  options: AddEventListenerOptions | null = null
+): UnsubscribeFunction {
+  const target = resolveTarget(targetOrComponent);
+  const controller = new AbortController();
+
+  target.addEventListener(
+    eventName,
+    callback as EventListener,
+    {
+      signal: controller.signal,
+      once: options?.once
+    }
+  );
+
+  return () => controller.abort();
+}
+
+const onceOptions = {once: true};
+
+export function once<Event extends keyof EventsMapping>(
+  targetOrComponent: ResolvableTarget,
+  eventName: Event,
+  callback: EventCallback<EventsMapping[Event]>
+): UnsubscribeFunction {
+  return on(
+    targetOrComponent,
+    eventName,
+    callback,
+    onceOptions
+  );
+}
+
+class TargetedEmitter {
+  readonly #element: ResolvableTarget;
+
+  constructor(targetOrComponent: ResolvableTarget) {
+    this.#element = targetOrComponent;
+  }
+
+  emit<Event extends keyof EventsMapping>(eventName: Event, details: EventsMapping[Event]): void {
+    emit(this.#element, eventName, details);
+  }
+
+  on<Event extends keyof EventsMapping>(eventName: Event, callback: EventCallback<EventsMapping[Event]>, options: AddEventListenerOptions | null = null): UnsubscribeFunction {
+    return on(this.#element, eventName, callback, options);
+  }
+
+  once<Event extends keyof EventsMapping>(eventName: Event, callback: EventCallback<EventsMapping[Event]>): UnsubscribeFunction {
+    return once(this.#element, eventName, callback);
+  }
+}
+
+export function emitterAt(targetOrComponent: ResolvableTarget): TargetedEmitter {
+  return new TargetedEmitter(targetOrComponent);
+}

src/lib/components/events/maintenance-popup-events.ts

@@ -0,0 +1,13 @@
+import type MaintenanceProfile from "$entities/MaintenanceProfile.ts";
+
+export const eventActiveProfileChanged = 'active-profile-changed';
+export const eventMaintenanceStateChanged = 'maintenance-state-change';
+export const eventTagsUpdated = 'tags-updated';
+
+type MaintenanceState = 'processing' | 'failed' | 'complete' | 'waiting';
+
+export interface MaintenancePopupEventsMap {
+  [eventActiveProfileChanged]: MaintenanceProfile | null;
+  [eventMaintenanceStateChanged]: MaintenanceState;
+  [eventTagsUpdated]: Map<string, string> | null;
+}