refactor(mediabunny): [PKG-MB-08] finish typed media capability boundaries

packages/artplayer-proxy-mediabunny/src/MediaBunnyEngine.ts

@@ -10,7 +10,7 @@ import { getHlsState } from './hls-state'
 import { createInput } from './input'
 import LoadSession from './load-session'
 import Playback from './playback'
-import { metadataBarrier, publish } from './readiness'
+import { metadataBarrier, publish, requireDecoder } from './readiness'
 import { selectPlaybackTracks } from './tracks'
 import VideoEngine from './VideoEngine.js'
 
@@ -150,6 +150,7 @@ export default class MediaBunnyEngine implements EnginePort {
     this.input = input
     this.media = media
     const metadata = metadataBarrier(() => {
+      requireDecoder(this)
       this.readyState = 1
       publish(this.events, current, ['loadedmetadata', 'durationchange', 'progress'])
     }, current)
@@ -159,6 +160,7 @@ export default class MediaBunnyEngine implements EnginePort {
       await Promise.all([video, audio])
       if (!current())
         return
+      requireDecoder(this)
       this.readyState = 4
       this.networkState = 1
       publish(this.events, current, ['loadeddata', 'canplay', 'canplaythrough', 'progress'])

packages/artplayer-proxy-mediabunny/src/engine-ports.ts

@@ -1,9 +1,10 @@
-import type { Input } from 'mediabunny'
+import type { AudioBufferSink, CanvasSink, Input } from 'mediabunny'
 import type { ProxyOptions } from './engine-types'
 import type EventTarget from './EventTarget'
 import type { PlaybackMedia } from './media'
 
 export interface AudioPort {
+  readonly audioSink: AudioBufferSink | null
   cancelPending: () => void
   readonly currentTime: number
   duration: number
@@ -19,6 +20,7 @@ export interface AudioPort {
 }
 
 export interface VideoPort {
+  readonly videoSink: CanvasSink | null
   cancelPending: () => void
   width: number
   height: number

packages/artplayer-proxy-mediabunny/src/playback.ts

@@ -1,6 +1,6 @@
 import type { PlaybackHost } from './engine-ports'
 import type { PlaybackMedia } from './media'
-import { publish } from './readiness'
+import { publish, requireDecoder } from './readiness'
 import { resolveDuration } from './tracks'
 
 interface Completion {
@@ -156,6 +156,7 @@ export default class Playback {
       await Promise.all([this.host.video.load(media), this.host.audio.load(media)])
       if (!current())
         return
+      requireDecoder(this.host)
       await Promise.all([this.host.video.seek(time), this.host.audio.seek(time)])
       if (current()) {
         this.host.readyState = 4

packages/artplayer-proxy-mediabunny/src/readiness.ts

@@ -1,5 +1,14 @@
+import type { PlaybackHost } from './engine-ports'
 import type EventTarget from './EventTarget'
 
+export function requireDecoder(host: Pick<PlaybackHost, 'audio' | 'video' | 'readyState'>): void {
+  // Sinks reflect the decoder's completed capability check; do not query the SDK twice.
+  if (host.audio.audioSink || host.video.videoSink)
+    return
+  host.readyState = 0
+  throw new Error('Input has no decodable audio or video tracks.')
+}
+
 export function publish(events: EventTarget, current: () => boolean, names: readonly string[]): void {
   for (const name of names) {
     if (!current())