feat: Ollama models command, with load/pull/delete and unload (#16)

src/lib/components/ChatView.tsx

@@ -3,9 +3,10 @@ import { useCallback, useEffect, useMemo, useState } from "react";
 import { readAttachment } from "../attachments";
 import { runAutoDelete } from "../cleanup";
 import { useChat, type ToolActivity } from "../hooks/useChat";
+import { usePreferences } from "../hooks/usePreferences";
 import { useVisionSupport } from "../hooks/useVision";
 import { buildThreadMarkdown, renderAttachments, type TranscriptOptions } from "../markdown";
-import { getLamPreferences } from "../preferences";
+import type { ResolvedPreferences } from "../preferences";
 import { deleteSession, listSessions, loadSession, summarizeSession } from "../sessions";
 import { resolveStartup } from "../startup";
 import { buildThread } from "../thread";
@@ -94,17 +95,49 @@ interface SessionRow {
   isActive: boolean;
 }
 
-export function ChatView({
+/** Shown while the conversation and the preferences are still being read. */
+function LoadingChat() {
+  return <List isLoading navigationTitle="Lam" searchBarPlaceholder="Loading conversations…" />;
+}
+
+/**
+ * The chat surface, once its preferences are known.
+ *
+ * Split in two so that {@link ChatView} can wait for the model before the state
+ * machine starts. `useChat` is created with the preferences it will use, so
+ * handing it preferences that are still loading would pin the conversation to
+ * whatever the preference said before the selection arrived.
+ *
+ * The outer half does nothing but that wait, and the loading state costs one
+ * LocalStorage read, which is a few milliseconds while the user is still moving
+ * their hands towards the keyboard.
+ */
+export function ChatView(props: ChatViewProps) {
+  const { preferences } = usePreferences();
+
+  if (!preferences) return <LoadingChat />;
+  return <ChatSession {...props} preferences={preferences} />;
+}
+
+interface ChatSessionProps extends ChatViewProps {
+  preferences: ResolvedPreferences;
+}
+
+function ChatSession({
+  preferences,
   initialSession,
   initialPrompt,
   initialSessionId,
   initialAttachmentPath,
   launchNote,
-}: ChatViewProps) {
-  const preferences = useMemo(() => getLamPreferences(), []);
-  const chat = useChat({ preferences, initialSession });
+}: ChatSessionProps) {
+  // The capability check is resolved before the chat exists, because its answer
+  // is part of the system prompt: a model that knows it can read images describes
+  // the one it is sent, and one that does not know reasons about itself instead.
+  const vision = useVisionSupport(preferences);
+  const chat = useChat({ preferences, initialSession, vision: vision.support });
   const { replaceSession } = chat;
-  const { canSeeImages } = useVisionSupport(preferences);
+  const { canSeeImages } = vision;
   const { activity } = chat;
 
   const [input, setInput] = useState(initialPrompt ?? "");
@@ -396,7 +429,7 @@ export function ChatView({
   };
 
   if (startup === "loading" || summaries === undefined) {
-    return <List isLoading navigationTitle="Lam" searchBarPlaceholder="Loading conversations…" />;
+    return <LoadingChat />;
   }
 
   const placeholder = chat.status ? `${chat.status}. Press ⏎ to stop` : "Lam is thinking. Press ⏎ to stop";