Upload updates

frontend/src/lib/uploadStatus.ts

@@ -0,0 +1,30 @@
+import { useQuery } from "@tanstack/react-query";
+
+import { api } from "@/lib/api";
+import { hasBackend } from "@/lib/backend";
+import type { UploadStatus } from "@/lib/types";
+import { useAuth } from "@/store/auth";
+
+export const uploadStatusQueryKey = ["upload-status"] as const;
+
+/**
+ * Poll the server-side upload pipeline while it has work and stop once it is
+ * idle. Shared by the Upload page and the shell indicator so both show the
+ * same state without extra requests.
+ */
+export function useUploadStatus(enabled = true) {
+  const user = useAuth((state) => state.user);
+  return useQuery({
+    queryKey: uploadStatusQueryKey,
+    queryFn: () => api<UploadStatus>("/api/uploads/status/"),
+    enabled: enabled && hasBackend() && Boolean(user?.can_upload),
+    // TanStack takes the smallest interval across the observers, so the
+    // Upload page and the shell pill can safely share this query.
+    refetchInterval: (query) => (query.state.data?.active ? 2_000 : false),
+  });
+}
+
+/** Ask the server to (re)start processing the caller's staged uploads. */
+export function postProcessUploads(): Promise<UploadStatus> {
+  return api<UploadStatus>("/api/uploads/process/", { method: "POST" });
+}