chore: merge blocksuite source code (#9213)

blocksuite/framework/sync/src/awareness/engine.ts

@@ -0,0 +1,18 @@
+import type { Awareness } from 'y-protocols/awareness';
+
+import type { AwarenessSource } from './source.js';
+
+export class AwarenessEngine {
+  constructor(
+    readonly awareness: Awareness,
+    readonly sources: AwarenessSource[]
+  ) {}
+
+  connect() {
+    this.sources.forEach(source => source.connect(this.awareness));
+  }
+
+  disconnect() {
+    this.sources.forEach(source => source.disconnect());
+  }
+}

blocksuite/framework/sync/src/awareness/impl/broadcast.ts

@@ -0,0 +1,73 @@
+import type { Awareness } from 'y-protocols/awareness';
+import {
+  applyAwarenessUpdate,
+  encodeAwarenessUpdate,
+} from 'y-protocols/awareness';
+
+import type { AwarenessSource } from '../source.js';
+
+type AwarenessChanges = Record<'added' | 'updated' | 'removed', number[]>;
+
+type ChannelMessage =
+  | { type: 'connect' }
+  | { type: 'update'; update: Uint8Array };
+
+export class BroadcastChannelAwarenessSource implements AwarenessSource {
+  awareness: Awareness | null = null;
+
+  channel: BroadcastChannel | null = null;
+
+  handleAwarenessUpdate = (changes: AwarenessChanges, origin: unknown) => {
+    if (origin === 'remote') {
+      return;
+    }
+
+    const changedClients = Object.values(changes).reduce((res, cur) =>
+      res.concat(cur)
+    );
+
+    const update = encodeAwarenessUpdate(this.awareness!, changedClients);
+    this.channel?.postMessage({
+      type: 'update',
+      update: update,
+    } satisfies ChannelMessage);
+  };
+
+  constructor(readonly channelName: string) {}
+
+  connect(awareness: Awareness): void {
+    this.channel = new BroadcastChannel(this.channelName);
+    this.channel.postMessage({
+      type: 'connect',
+    } satisfies ChannelMessage);
+    this.awareness = awareness;
+    awareness.on('update', this.handleAwarenessUpdate);
+    this.channel.addEventListener(
+      'message',
+      (event: MessageEvent<ChannelMessage>) => {
+        this.handleChannelMessage(event);
+      }
+    );
+  }
+
+  disconnect(): void {
+    this.awareness?.off('update', this.handleAwarenessUpdate);
+    this.channel?.close();
+    this.channel = null;
+  }
+
+  handleChannelMessage(event: MessageEvent<ChannelMessage>) {
+    if (event.data.type === 'update') {
+      const update = event.data.update;
+      applyAwarenessUpdate(this.awareness!, update, 'remote');
+    }
+    if (event.data.type === 'connect') {
+      this.channel?.postMessage({
+        type: 'update',
+        update: encodeAwarenessUpdate(this.awareness!, [
+          this.awareness!.clientID,
+        ]),
+      } satisfies ChannelMessage);
+    }
+  }
+}

blocksuite/framework/sync/src/awareness/impl/index.ts

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+export * from './broadcast.js';

blocksuite/framework/sync/src/awareness/index.ts

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+export * from './engine.js';
+export * from './impl/index.js';
+export * from './source.js';

blocksuite/framework/sync/src/awareness/source.ts

@@ -0,0 +1,6 @@
+import type { Awareness } from 'y-protocols/awareness';
+
+export interface AwarenessSource {
+  connect(awareness: Awareness): void;
+  disconnect(): void;
+}