feat(models): show LangBot Models availability

web/src/app/home/components/model-availability/useLangBotModelAvailability.ts

@@ -0,0 +1,63 @@
+import { useEffect, useState } from 'react';
+import type { LangBotModelAvailability } from '@/app/infra/entities/api';
+import { httpClient } from '@/app/infra/http/HttpClient';
+
+const CACHE_TTL_MS = 60_000;
+
+type AvailabilityMap = Record<string, LangBotModelAvailability>;
+
+let cachedAvailability: AvailabilityMap | null = null;
+let cacheExpiresAt = 0;
+let pendingRequest: Promise<AvailabilityMap> | null = null;
+
+async function loadAvailability(): Promise<AvailabilityMap> {
+  if (cachedAvailability && Date.now() < cacheExpiresAt) {
+    return cachedAvailability;
+  }
+  if (pendingRequest) return pendingRequest;
+
+  pendingRequest = httpClient
+    .getLangBotModelAvailability()
+    .then((response) => {
+      const next: AvailabilityMap = {};
+      for (const item of response.models) {
+        next[item.uuid] = item.availability;
+        next[item.model_id] = item.availability;
+      }
+      cachedAvailability = next;
+      cacheExpiresAt = Date.now() + CACHE_TTL_MS;
+      return next;
+    })
+    .finally(() => {
+      pendingRequest = null;
+    });
+  return pendingRequest;
+}
+
+export function useLangBotModelAvailability(enabled = true) {
+  const [availability, setAvailability] = useState<AvailabilityMap>(
+    cachedAvailability ?? {},
+  );
+  const [loaded, setLoaded] = useState(
+    cachedAvailability !== null && Date.now() < cacheExpiresAt,
+  );
+
+  useEffect(() => {
+    if (!enabled) return;
+    let active = true;
+    loadAvailability()
+      .then((result) => {
+        if (!active) return;
+        setAvailability(result);
+        setLoaded(true);
+      })
+      .catch(() => {
+        // Availability is supplementary; model configuration remains usable.
+      });
+    return () => {
+      active = false;
+    };
+  }, [enabled]);
+
+  return { availability, loaded };
+}