chore: establish learning module baseline

OpenMAIC/lib/media/resolve-audio-bytes.ts

@@ -0,0 +1,39 @@
+import { db } from '@/lib/utils/database';
+import { isConcreteMediaAddress } from './resolve-media-ref';
+import { withAssetUrl } from './use-asset-url';
+
+/**
+ * Bytes an audio reference currently resolves to.
+ *
+ * A stable-id regeneration commits the replaced narration to the pool first and
+ * deliberately keeps the same id; if the `audioFiles` mirror write then fails
+ * (quota pressure, a transient IndexedDB error) the row is stale while the pool
+ * is current. Every consumer of allocated audio therefore resolves through this
+ * one function, with Dexie kept as the fallback for legacy and imported rows
+ * that were never pool-backed.
+ */
+export async function resolveAudioBlob(audioId: string): Promise<Blob | null> {
+  const pooled = await pooledAudioBlob(audioId);
+  if (pooled) return pooled;
+  const record = await db.audioFiles.get(audioId);
+  return record?.blob ?? null;
+}
+
+/** Resolve several ids at once, preserving input order. */
+export async function resolveAudioBlobs(
+  audioIds: readonly string[],
+): Promise<ReadonlyArray<Blob | null>> {
+  return Promise.all(audioIds.map((audioId) => resolveAudioBlob(audioId)));
+}
+
+async function pooledAudioBlob(audioId: string): Promise<Blob | null> {
+  if (!audioId || isConcreteMediaAddress(audioId)) return null;
+  try {
+    return await withAssetUrl(audioId, async (url) =>
+      url ? fetch(url).then((response) => response.blob()) : null,
+    );
+  } catch {
+    // Stored rows stay the fallback when the pool is unavailable.
+    return null;
+  }
+}