fix: add timeout/retry for setup status check (#457)

- add bounded timeout+retry helper for /api/setup checks
- show actionable setup error state with Retry button
- avoid blank-screen fallback when setup status check fails
- add unit tests for retry helper

Fixes #456

src/app/setup/page.tsx

@@ -5,6 +5,7 @@ import Image from 'next/image'
 import { useTranslations } from 'next-intl'
 import { Button } from '@/components/ui/button'
 import { LanguageSwitcherSelect } from '@/components/ui/language-switcher'
+import { fetchSetupStatusWithRetry } from '@/lib/setup-status'
 
 type SetupStep = 'form' | 'creating'
 
@@ -13,6 +14,9 @@ interface ProgressStep {
   status: 'pending' | 'active' | 'done' | 'error'
 }
 
+const SETUP_STATUS_TIMEOUT_MS = 5000
+const SETUP_STATUS_ATTEMPTS = 3
+
 function getInitialProgress(t: (key: string) => string): ProgressStep[] {
   return [
     { label: t('validatingCredentials'), status: 'pending' },
@@ -72,23 +76,35 @@ export default function SetupPage() {
   const [progress, setProgress] = useState<ProgressStep[]>(() => getInitialProgress(t))
   const [checking, setChecking] = useState(true)
   const [setupAvailable, setSetupAvailable] = useState(false)
+  const [setupCheckTick, setSetupCheckTick] = useState(0)
+
+  const checkSetupStatus = useCallback(async () => {
+    setChecking(true)
+    setError('')
+
+    try {
+      const data = await fetchSetupStatusWithRetry(fetch, {
+        attempts: SETUP_STATUS_ATTEMPTS,
+        timeoutMs: SETUP_STATUS_TIMEOUT_MS,
+      })
+
+      if (!data.needsSetup) {
+        window.location.href = '/login'
+        return
+      }
+
+      setSetupAvailable(true)
+      setChecking(false)
+    } catch {
+      setSetupAvailable(false)
+      setError(t('failedToCheckSetup'))
+      setChecking(false)
+    }
+  }, [t])
 
   useEffect(() => {
-    fetch('/api/setup')
-      .then((res) => res.json())
-      .then((data) => {
-        if (!data.needsSetup) {
-          window.location.href = '/login'
-          return
-        }
-        setSetupAvailable(true)
-        setChecking(false)
-      })
-      .catch(() => {
-        setError(t('failedToCheckSetup'))
-        setChecking(false)
-      })
-  }, [t])
+    checkSetupStatus()
+  }, [checkSetupStatus, setupCheckTick])
 
   const updateProgress = useCallback((index: number, status: ProgressStep['status']) => {
     setProgress((prev) => prev.map((s, i) => (i === index ? { ...s, status } : s)))
@@ -174,7 +190,21 @@ export default function SetupPage() {
   }
 
   if (!setupAvailable) {
-    return null
+    return (
+      <div className="min-h-screen flex items-center justify-center bg-background p-4">
+        <div className="w-full max-w-sm rounded-lg border border-destructive/20 bg-destructive/10 p-4 text-sm text-destructive space-y-3">
+          <p>{error || t('failedToCheckSetup')}</p>
+          <Button
+            type="button"
+            variant="secondary"
+            onClick={() => setSetupCheckTick((v) => v + 1)}
+            className="w-full"
+          >
+            {tc('retry')}
+          </Button>
+        </div>
+      </div>
+    )
   }
 
   return (

src/lib/__tests__/setup-status.test.ts

@@ -0,0 +1,49 @@
+import { describe, it, expect, vi } from 'vitest'
+import { fetchSetupStatusWithRetry } from '@/lib/setup-status'
+
+describe('fetchSetupStatusWithRetry', () => {
+  it('returns setup status on success', async () => {
+    const fetchMock = vi.fn().mockResolvedValue({
+      ok: true,
+      json: async () => ({ needsSetup: true }),
+    })
+
+    const result = await fetchSetupStatusWithRetry(fetchMock as any, { attempts: 2, timeoutMs: 2000 })
+
+    expect(result).toEqual({ needsSetup: true })
+    expect(fetchMock).toHaveBeenCalledTimes(1)
+  })
+
+  it('retries on failure and eventually succeeds', async () => {
+    const fetchMock = vi.fn()
+      .mockRejectedValueOnce(new Error('network down'))
+      .mockResolvedValueOnce({
+        ok: true,
+        json: async () => ({ needsSetup: false }),
+      })
+
+    const result = await fetchSetupStatusWithRetry(fetchMock as any, { attempts: 3, timeoutMs: 2000 })
+
+    expect(result).toEqual({ needsSetup: false })
+    expect(fetchMock).toHaveBeenCalledTimes(2)
+  })
+
+  it('throws after attempts are exhausted', async () => {
+    const fetchMock = vi.fn().mockRejectedValue(new Error('still failing'))
+
+    await expect(fetchSetupStatusWithRetry(fetchMock as any, { attempts: 2, timeoutMs: 2000 }))
+      .rejects.toThrow('still failing')
+
+    expect(fetchMock).toHaveBeenCalledTimes(2)
+  })
+
+  it('throws on invalid payload shape', async () => {
+    const fetchMock = vi.fn().mockResolvedValue({
+      ok: true,
+      json: async () => ({ needsSetup: 'yes' }),
+    })
+
+    await expect(fetchSetupStatusWithRetry(fetchMock as any, { attempts: 1, timeoutMs: 2000 }))
+      .rejects.toThrow('Invalid setup status response')
+  })
+})

src/lib/setup-status.ts

@@ -0,0 +1,53 @@
+export interface FetchSetupStatusOptions {
+  attempts?: number
+  timeoutMs?: number
+}
+
+export interface SetupStatusResponse {
+  needsSetup: boolean
+}
+
+/**
+ * Fetch setup status with timeout + bounded retries.
+ */
+export async function fetchSetupStatusWithRetry(
+  fetchFn: typeof fetch,
+  options: FetchSetupStatusOptions = {}
+): Promise<SetupStatusResponse> {
+  const attempts = Math.max(1, options.attempts ?? 3)
+  const timeoutMs = Math.max(1000, options.timeoutMs ?? 5000)
+
+  let lastError: Error | null = null
+
+  for (let attempt = 1; attempt <= attempts; attempt++) {
+    const controller = new AbortController()
+    const timeoutId = setTimeout(() => controller.abort('timeout'), timeoutMs)
+
+    try {
+      const res = await fetchFn('/api/setup', { signal: controller.signal })
+      if (!res.ok) {
+        throw new Error(`Setup status check failed (${res.status})`)
+      }
+      const data = await res.json() as SetupStatusResponse
+      if (typeof data?.needsSetup !== 'boolean') {
+        throw new Error('Invalid setup status response')
+      }
+      return data
+    } catch (error: any) {
+      if (error?.name === 'AbortError') {
+        lastError = new Error('Setup status request timed out')
+      } else {
+        lastError = error instanceof Error ? error : new Error('Setup status request failed')
+      }
+
+      if (attempt < attempts) {
+        // tiny backoff to avoid immediate hammering during transient stalls
+        await new Promise(resolve => setTimeout(resolve, 250 * attempt))
+      }
+    } finally {
+      clearTimeout(timeoutId)
+    }
+  }
+
+  throw (lastError ?? new Error('Failed to check setup status'))
+}