refactor: Refactor media loading manager for improved robustness (#2464)

src/components-lib/live/live-controller.ts

@@ -1,106 +0,0 @@
-import { LitElement, ReactiveController } from 'lit';
-import { MediaLoadedInfo } from '../../types.js';
-import {
-  AdvancedCameraCardMediaLoadedEventTarget,
-  dispatchExistingMediaLoadedInfoAsEvent,
-} from '../../utils/media-info.js';
-
-interface LiveViewContext {
-  // A cameraID override (used for dependencies/substreams to force a different
-  // camera to be live rather than the camera selected in the view).
-  overrides?: Map<string, string>;
-}
-
-declare module 'view' {
-  interface ViewContext {
-    live?: LiveViewContext;
-  }
-}
-
-interface LastMediaLoadedInfo {
-  mediaLoadedInfo: MediaLoadedInfo;
-  source: EventTarget;
-}
-
-type LiveControllerHost = LitElement & AdvancedCameraCardMediaLoadedEventTarget;
-
-export class LiveController implements ReactiveController {
-  private _host: LiveControllerHost;
-
-  // Whether or not the live view is currently in the background (i.e. preloaded
-  // but not visible).
-  private _inBackground = false;
-
-  // Intersection handler is used to detect when the live view flips between
-  // foreground and background (in preload mode).
-  private _intersectionObserver: IntersectionObserver;
-
-  // MediaLoadedInfo object and target from the underlying live media. In the
-  // case of pre-loading these may be propagated later (from the original
-  // source).
-  private _lastMediaLoadedInfo: LastMediaLoadedInfo | null = null;
-
-  constructor(host: LiveControllerHost) {
-    this._host = host;
-
-    host.addController(this);
-
-    this._intersectionObserver = new IntersectionObserver(
-      this._intersectionHandler.bind(this),
-    );
-  }
-
-  public hostConnected(): void {
-    this._intersectionObserver.observe(this._host);
-
-    this._host.addEventListener(
-      'advanced-camera-card:media:loaded',
-      this._handleMediaLoaded,
-    );
-  }
-
-  public hostDisconnected(): void {
-    this._intersectionObserver.disconnect();
-
-    this._host.removeEventListener(
-      'advanced-camera-card:media:loaded',
-      this._handleMediaLoaded,
-    );
-  }
-
-  public isInBackground(): boolean {
-    return this._inBackground;
-  }
-
-  private _handleMediaLoaded = (ev: CustomEvent<MediaLoadedInfo>): void => {
-    this._lastMediaLoadedInfo = {
-      source: ev.composedPath()[0],
-      mediaLoadedInfo: ev.detail,
-    };
-
-    if (this._inBackground) {
-      ev.stopPropagation();
-    }
-  };
-
-  private _intersectionHandler(entries: IntersectionObserverEntry[]): void {
-    const wasInBackground = this._inBackground;
-    this._inBackground = !entries.some((entry) => entry.isIntersecting);
-
-    if (!this._inBackground && this._lastMediaLoadedInfo) {
-      // If this isn't being rendered in the background, the last render did not
-      // generate a message and there's a saved MediaInfo, dispatch it upwards.
-      dispatchExistingMediaLoadedInfoAsEvent(
-        // Specifically dispatch the event "where it came from", as otherwise
-        // the intermediate layers (e.g. media-carousel which controls the title
-        // popups) will not re-receive the events.
-        this._lastMediaLoadedInfo.source,
-        this._lastMediaLoadedInfo.mediaLoadedInfo,
-      );
-    }
-
-    if (wasInBackground !== this._inBackground) {
-      this._host.requestUpdate();
-    }
-  }
-}

src/components-lib/live/types.ts

@@ -0,0 +1,11 @@
+export interface LiveViewContext {
+  // A cameraID override (used for dependencies/substreams to force a different
+  // camera to be live rather than the camera selected in the view).
+  overrides?: Map<string, string>;
+}
+
+declare module 'view' {
+  interface ViewContext {
+    live?: LiveViewContext;
+  }
+}