bug fixes, and performance improvements, and drawer

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,
+    };
+};