feat(nbstore): add doc sync state (#9131)

packages/common/nbstore/src/sync/index.ts

@@ -1,10 +1,21 @@
+import { combineLatest, map, type Observable, of } from 'rxjs';
+
 import type { BlobStorage, DocStorage, SpaceStorage } from '../storage';
+import type { AwarenessStorage } from '../storage/awareness';
+import { AwarenessSync } from './awareness';
 import { BlobSync } from './blob';
-import { DocSync } from './doc';
+import { DocSync, type DocSyncState } from './doc';
+
+export interface SyncState {
+  doc?: DocSyncState;
+}
 
 export class Sync {
-  private readonly doc: DocSync | null;
-  private readonly blob: BlobSync | null;
+  readonly doc: DocSync | null;
+  readonly blob: BlobSync | null;
+  readonly awareness: AwarenessSync | null;
+
+  readonly state$: Observable<SyncState>;
 
   constructor(
     readonly local: SpaceStorage,
@@ -13,6 +24,7 @@ export class Sync {
     const doc = local.tryGet('doc');
     const blob = local.tryGet('blob');
     const sync = local.tryGet('sync');
+    const awareness = local.tryGet('awareness');
 
     this.doc =
       doc && sync
@@ -32,6 +44,18 @@ export class Sync {
             .filter((v): v is BlobStorage => !!v)
         )
       : null;
+    this.awareness = awareness
+      ? new AwarenessSync(
+          awareness,
+          peers
+            .map(peer => peer.tryGet('awareness'))
+            .filter((v): v is AwarenessStorage => !!v)
+        )
+      : null;
+
+    this.state$ = combineLatest([this.doc?.state$ ?? of(undefined)]).pipe(
+      map(([doc]) => ({ doc }))
+    );
   }
 
   start() {