bug fixes, and performance improvements, and drawer

server/utils/events.ts

@@ -1,5 +1,9 @@
+import { createLiveTopicText } from './live-topic-text';
+
+type StreamSink = Pick<ReadableStreamDefaultController, 'enqueue'>;
+
 interface StreamConnection {
-    controller: ReadableStreamDefaultController;
+    controller: StreamSink;
     lastPing: number;
     subscribedAt: number;
 }
@@ -91,9 +95,13 @@ export const userEvents = {
 };
 
 const topicSubscribers = new Map<string, Set<StreamConnection>>();
+const liveTopicText = createLiveTopicText();
 
 export const topicEvents = {
-    subscribe(topicId: string, controller: ReadableStreamDefaultController) {
+    applyLiveText: liveTopicText.apply,
+    clearLiveText: liveTopicText.removeMessage,
+
+    subscribe(topicId: string, controller: StreamSink) {
         if (!topicSubscribers.has(topicId)) {
             topicSubscribers.set(topicId, new Set());
         }
@@ -120,7 +128,7 @@ export const topicEvents = {
         (conn as any).pingInterval = pingInterval;
     },
 
-    unsubscribe(topicId: string, controller: ReadableStreamDefaultController) {
+    unsubscribe(topicId: string, controller: StreamSink) {
         const connections = topicSubscribers.get(topicId);
         if (!connections) return;
 
@@ -137,14 +145,14 @@ export const topicEvents = {
     },
 
     async emit(topicId: string, events: Array<{ type: string; payload: any; timestamp?: number }> | { type: string; payload: any; timestamp?: number }) {
-        const connections = topicSubscribers.get(topicId);
-        if (!connections || connections.size === 0) return;
-
         if (!Array.isArray(events)) {
             events = [events];
         }
 
         for (const event of events) {
+            liveTopicText.update(topicId, event);
+            const connections = topicSubscribers.get(topicId);
+            if (!connections || connections.size === 0) continue;
             const timestamp = event.timestamp ?? Date.now();
             const data = `data: ${JSON.stringify({ ...event, timestamp })}\n\n`;
 

server/utils/live-topic-text.ts

@@ -0,0 +1,65 @@
+import { appendTextDelta } from '../../utils/topic-sync';
+
+interface LivePart {
+    messageId: string;
+    part: Record<string, any> & { id: string; content: string };
+}
+
+/** Covers the interval between an emitted delta and its throttled DB write. */
+export const createLiveTopicText = () => {
+    const topics = new Map<string, Map<string, LivePart>>();
+
+    const removeMessage = (topicId: string, messageId: string) => {
+        const parts = topics.get(topicId);
+        if (!parts) return;
+        for (const [id, entry] of parts) {
+            if (entry.messageId === messageId) parts.delete(id);
+        }
+        if (parts.size === 0) topics.delete(topicId);
+    };
+
+    return {
+        update(topicId: string, event: { type: string; payload: any }) {
+            const { type, payload } = event;
+            if (type === 'text-start') {
+                let parts = topics.get(topicId);
+                if (!parts) topics.set(topicId, parts = new Map());
+                parts.set(payload.part.id, {
+                    messageId: payload.messageId,
+                    part: { ...payload.part, toolCall: null, content: payload.part.content ?? '' },
+                });
+            } else if (type === 'text-delta') {
+                const entry = topics.get(topicId)?.get(payload.partId);
+                if (entry) {
+                    entry.part.content = appendTextDelta(entry.part.content, payload.content, payload.offset);
+                    entry.part.lastUpdatedAt = payload.lastUpdatedAt;
+                }
+            } else if (type === 'text-end' || type === 'text-delete') {
+                const parts = topics.get(topicId);
+                parts?.delete(payload.partId);
+                if (parts?.size === 0) topics.delete(topicId);
+            } else if (type === 'MESSAGE_DELETED') {
+                removeMessage(topicId, payload.id);
+            }
+        },
+        apply(topicId: string, messages: { id: string; parts: any[] }[]) {
+            const parts = topics.get(topicId);
+            if (!parts) return;
+            const byId = new Map(messages.map(message => [message.id, message]));
+            for (const entry of parts.values()) {
+                const message = byId.get(entry.messageId);
+                if (!message) continue;
+                const existing = message.parts.find(part => part.id === entry.part.id);
+                if (existing) {
+                    if (!existing.finished && (existing.content?.length ?? 0) <= entry.part.content.length) {
+                        existing.content = entry.part.content;
+                        existing.lastUpdatedAt = entry.part.lastUpdatedAt;
+                    }
+                } else {
+                    message.parts.push({ ...entry.part });
+                }
+            }
+        },
+        removeMessage,
+    };
+};

server/utils/renames.ts

@@ -1,31 +1,21 @@
-interface PendingRename {
-    topicId: string;
-    abortController: AbortController;
-}
+const pendingRenames = new Map<string, { attemptId: string; controller: AbortController }>();
 
-const pendingRenames: Map<string, AbortController> = new Map();
-
-export const cancelPendingRename = (topicId: string) => {
-    const pendingRename = pendingRenames.get(topicId);
-    if (pendingRename) {
-        pendingRename.abort();
-        pendingRenames.delete(topicId);
-        return true;
-    }
-
-    return false;
-};
-
-export const completeRename = (topicId: string) => {
-    const controller = pendingRenames.get(topicId);
-    if (controller) {
+export const cancelPendingRename = (topicId: string, attemptId?: string | null) => {
+    const pending = pendingRenames.get(topicId);
+    if (pending && pending.attemptId === attemptId) {
+        pending.controller.abort();
         pendingRenames.delete(topicId);
     }
 };
 
-export const addPendingRename = (topicId: string) => {
-    const abortController = new AbortController();
+export const completeRename = (topicId: string, attemptId: string) => {
+    if (pendingRenames.get(topicId)?.attemptId === attemptId) {
+        pendingRenames.delete(topicId);
+    }
+};
 
-    pendingRenames.set(topicId, abortController);
-    return abortController;
-};
+export const addPendingRename = (topicId: string, attemptId: string) => {
+    const controller = new AbortController();
+    pendingRenames.set(topicId, { attemptId, controller });
+    return controller;
+};

server/utils/search.ts

@@ -1,4 +1,5 @@
 import type { Result } from "../../types/result";
+import { randomUUID } from "node:crypto";
 import { z } from "zod";
 import { Err, Ok } from "../../types/result";
 
@@ -20,6 +21,7 @@ export const searchOutputSchema = z.object({
     results: z.array(z.object({
         title: z.string(),
         link: z.string(),
+        sourceId: z.string().describe('Copy this exact ID into [[cite:ID]]. The literal "cite:" prefix is required; [[ID]] is invalid.').optional(),
         snippet: z.string(),
     })),
     warnings: z.array(z.object({ engine: z.string(), reason: z.string() })),
@@ -43,6 +45,7 @@ export const readSearchResponse = (body: unknown): Result<SearchOutput, string>
     }
     return Ok({
         results: parsed.data.results.map(item => ({
+            sourceId: `s${randomUUID().replaceAll("-", "")}`,
             title: item.title,
             link: item.url,
             snippet: item.content,

server/utils/topic-snapshot-stream.ts

@@ -0,0 +1,70 @@
+import { createHash } from 'node:crypto';
+import { Err, Ok } from '../../types/result';
+import { serializeTopicSnapshot } from '../../utils/topic-sync';
+import { topicEvents } from './events';
+
+interface TopicSnapshot {
+    messages: { id: string; parts: any[] }[];
+}
+
+export const createTopicSnapshotStream = (topicId: string, offeredFingerprint: unknown) => {
+    let controller: ReadableStreamDefaultController | undefined;
+    let closed = false;
+    const buffered: string[] = [];
+    const sink = {
+        enqueue(frame: string) {
+            if (closed) return;
+            if (controller) controller.enqueue(frame);
+            else buffered.push(frame);
+        },
+    };
+    const close = () => {
+        closed = true;
+        topicEvents.unsubscribe(topicId, sink);
+        buffered.length = 0;
+    };
+
+    return {
+        close,
+        async open(readSnapshot: () => Promise<TopicSnapshot | undefined>) {
+            if (closed) return Err('closed' as const);
+            // Subscribe before reading: changes during the query must not be lost.
+            topicEvents.subscribe(topicId, sink);
+            let topic;
+            try {
+                topic = await readSnapshot();
+            } catch (error) {
+                close();
+                console.error('Failed to read topic snapshot', error);
+                return Err('read-failed' as const);
+            }
+            if (closed || !topic) {
+                close();
+                return Err('not-found' as const);
+            }
+            // Include deltas already emitted but not yet flushed to PostgreSQL.
+            topicEvents.applyLiveText(topicId, topic.messages);
+            const fingerprint = createHash('sha256').update(serializeTopicSnapshot(topic)).digest('hex');
+            const matches = offeredFingerprint === fingerprint;
+
+            return Ok(new ReadableStream<string>({
+                start(streamController) {
+                    controller = streamController;
+                    controller.enqueue(`data: ${JSON.stringify(matches
+                        ? { type: 'synced', payload: { id: topicId } }
+                        : { type: 'initial_state', payload: topic })}\n\n`);
+                    for (const frame of buffered) {
+                        if (frame.startsWith('data: ')) {
+                            const replay = { ...JSON.parse(frame.slice(6)), replay: true };
+                            controller.enqueue(`data: ${JSON.stringify(replay)}\n\n`);
+                        } else {
+                            controller.enqueue(frame);
+                        }
+                    }
+                    buffered.length = 0;
+                },
+                cancel: close,
+            }));
+        },
+    };
+};