bug fixes, and performance improvements, and drawer

utils/message.ts

@@ -1,9 +1,86 @@
 import type { AssistantContent, FilePart, ImagePart, JSONValue, ModelMessage, ToolContent } from "ai";
-import { ToolCallType } from "~~/drizzle/schema";
-import { Err, Ok, type Result } from "~~/types/result";
-import type { Message, MessageEntity } from "~/composables/useChat";
-import type { Agent } from "~/composables/useAgents";
-import { resolveFileUrl } from "~~/utils/url";
+import { ToolCallType } from "../drizzle/schema";
+import { Err, Ok, type Result } from "../types/result";
+import type { Message, MessageEntity } from "../app/composables/useChat";
+import type { Agent } from "../app/composables/useAgents";
+import { resolveFileUrl } from "./url";
+
+export const getActiveMessage = <T extends { id: string; deleted?: boolean | null; activeChildId?: string | null; children: (T | undefined)[] }>(
+    message: T
+): T | null => {
+    if (message.activeChildId && message.children.length > 0) {
+        const child = message.children.find(c => c?.id === message.activeChildId);
+        if (child) {
+            return child;
+        }
+    }
+
+    if (message.deleted === true) {
+        if (message.children.length > 0 && message.children[0]) {
+            return message.children[0];
+        }
+        return null;
+    }
+
+    return message;
+};
+
+export const getMessageCount = (message: {
+    deleted?: boolean | null;
+    children: unknown[];
+}): number => {
+    if (message.deleted === true) {
+        return message.children.length;
+    }
+
+    return message.children.length + 1;
+};
+
+export const getCurrentChildIndex = (message: {
+    deleted?: boolean | null;
+    activeChildId?: string | null;
+    children: ({ id: string } | undefined)[];
+}): number => {
+    if (message.deleted === true) {
+        if (!message.activeChildId) {
+            return 0;
+        }
+        const idx = message.children.findIndex(c => c?.id === message.activeChildId);
+        return idx >= 0 ? idx : 0;
+    }
+
+    if (!message.activeChildId) {
+        return 0;
+    }
+    const idx = message.children.findIndex(c => c?.id === message.activeChildId);
+    return idx >= 0 ? idx + 1 : 0;
+};
+
+export const getNextActiveChildId = (
+    message: {
+        deleted?: boolean | null;
+        activeChildId?: string | null;
+        children: ({ id: string } | undefined)[];
+    },
+    direction: -1 | 1
+): string | null => {
+    const allItems = message.deleted === true
+        ? message.children
+        : [null, ...message.children];
+
+    const currentIdx = allItems.findIndex(item => {
+        if (!item) {
+            return !message.activeChildId;
+        }
+        return item.id === message.activeChildId;
+    });
+
+    const validCurrentIdx = currentIdx >= 0 ? currentIdx : 0;
+    const newIdx = Math.max(0, Math.min(allItems.length - 1, validCurrentIdx + direction));
+    const newItem = allItems[newIdx];
+
+    return newItem?.id ?? null;
+};
 
 export const buildMessageTree = (flatMessages: MessageEntity[]) => {
     const messagesMap = new Map(flatMessages.map(m => [m.id, { ...m, children: [] as MessageEntity[] }]));
@@ -16,26 +93,21 @@ export const buildMessageTree = (flatMessages: MessageEntity[]) => {
             roots.push(msg);
         }
     }
-    return roots;
+    return roots.filter(root => !root.deleted || root.children.length > 0);
 };
 
 export const buildFocusedMessageTree = (messages: Readonly<Message[]>): MessageEntity[] => {
-    let focusedMessageTree: MessageEntity[] = [];
+    const focusedMessageTree: MessageEntity[] = [];
 
     for (const message of messages) {
-        if (message.activeChildId && message.children.length > 0) {
-            const activeChild = message.children.find(c => c?.id === message.activeChildId);
-            if (activeChild) {
-                focusedMessageTree.push(activeChild);
-                continue;
-            }
+        const activeMessage = getActiveMessage(message);
+        if (activeMessage) {
+            focusedMessageTree.push(activeMessage);
         }
-
-        focusedMessageTree.push(message);
     }
 
     return focusedMessageTree;
-}
+};
 
 export interface MarshallOptions {
     signFileUrl?: (fileKey: string) => string;

utils/topic-sync.ts

@@ -0,0 +1,21 @@
+/** Stable across database Dates, JSON SSE payloads, and Nuxt hydration. */
+export const serializeTopicSnapshot = (topic: unknown): string => JSON.stringify(topic, (_key, value) => {
+    if (value === null || typeof value !== 'object' || Array.isArray(value)) {
+        return value;
+    }
+
+    return Object.fromEntries(Object.keys(value).sort().map(key => [key, value[key]]));
+});
+
+/** Absolute offsets make replay across a snapshot boundary idempotent. */
+export const appendTextDelta = (current: string, content: string, offset?: number): string => {
+    if (offset === undefined) {
+        return current + content;
+    }
+    if (offset > current.length) {
+        // A gap requires reconciliation, not silently concatenating corrupt text.
+        return current;
+    }
+    const overlap = current.length - offset;
+    return overlap >= content.length ? current : current + content.slice(overlap);
+};

utils/topic-title.ts

@@ -0,0 +1,9 @@
+export const provisionalTopicTitle = (message?: {
+    content: string;
+    files?: { name: string }[];
+    fileIds?: string[];
+}): string => {
+    const line = message?.content.split(/\r?\n/).map(line => line.trim()).find(Boolean);
+    const title = line || message?.files?.[0]?.name || (message?.fileIds?.length ? "Attached files" : "New Topic");
+    return title.replace(/\s+/g, " ").slice(0, 100);
+};