refactor(vast): [PKG-VAST-03] isolate lifecycle ownership checkpoint

packages/artplayer-plugin-vast/src/index.ts

@@ -0,0 +1,48 @@
+import type Artplayer from 'artplayer'
+import type { Callback, Result } from './types'
+import { loadImaSdk } from './sdk'
+import { createSession } from './session'
+
+export default function artplayerPluginVast(callback?: Callback) {
+  return async (art: Artplayer): Promise<Result> => {
+    let disposed = false
+    let session: ReturnType<typeof createSession> | undefined
+    const closed = () => disposed || art.isDestroy
+    const result: Result = { name: 'artplayerPluginVast', destroy: () => session?.destroy() }
+    function dispose(): void {
+      if (disposed)
+        return
+      disposed = true
+      try {
+        art.off('destroy', dispose)
+      }
+      finally { session?.destroy() }
+    }
+    if (closed())
+      return result
+    art.on('destroy', dispose)
+    try {
+      if (closed())
+        return result
+      const ima = await loadImaSdk()
+      if (closed())
+        return result
+      const utils = (art.constructor as typeof Artplayer).utils
+      session = createSession(art, ima, utils, closed)
+      if (closed()) {
+        dispose()
+        return result
+      }
+      if (typeof callback === 'function')
+        await callback(session.context)
+      return result
+    }
+    catch (error) {
+      try {
+        dispose()
+      }
+      catch (cleanupError) { console.error('VAST cleanup error:', cleanupError) }
+      throw error
+    }
+  }
+}