feat(flutter): GoRouter shell + version gate + auth-aware redirects

Cold launch flow: no server-url -> /server-url. URL set, no token -> /login. Token present -> /home with shell. VersionGate runs once when the URL changes, hits /healthz, blocks if min_client_version > package version. /home is a placeholder until Task 14. Replaces Navigator.pushReplacementNamed in server_url_screen + login_screen with context.go now that go_router owns the routes.
2026-05-02 17:24:08 -04:00
parent 9cbbfcff6c
commit d115c267f4
6 changed files with 144 additions and 13 deletions
@@ -0,0 +1,67 @@
+import 'package:flutter/material.dart';
+import 'package:flutter_riverpod/flutter_riverpod.dart';
+import 'package:package_info_plus/package_info_plus.dart';
+import 'package:pub_semver/pub_semver.dart';
+
+import '../../api/client.dart';
+import '../../api/endpoints/health.dart';
+import '../../auth/auth_provider.dart';
+
+final _versionCheckProvider = FutureProvider<_VersionResult>((ref) async {
+  final url = await ref.watch(serverUrlProvider.future);
+  if (url == null) return _VersionResult.skipped;
+  final dio = ApiClient.buildDio(baseUrl: url, tokenResolver: () async => null);
+  final body = await HealthApi(dio).check();
+  final min = body['min_client_version'];
+  if (min == null || min.isEmpty) return _VersionResult.skipped;
+  final info = await PackageInfo.fromPlatform();
+  final mine = Version.parse(info.version);
+  final required = Version.parse(min);
+  return mine < required ? _VersionResult.tooOld : _VersionResult.ok;
+});
+
+enum _VersionResult { ok, tooOld, skipped }
+
+class VersionGate extends ConsumerWidget {
+  const VersionGate({required this.child, super.key});
+  final Widget child;
+
+  @override
+  Widget build(BuildContext context, WidgetRef ref) {
+    return ref.watch(_versionCheckProvider).when(
+          data: (r) => r == _VersionResult.tooOld ? const _TooOldScreen() : child,
+          error: (_, __) => child, // soft-fail if /healthz is unreachable; let the rest of the flow surface a real error
+          loading: () => const Scaffold(body: Center(child: CircularProgressIndicator())),
+        );
+  }
+}
+
+class _TooOldScreen extends StatelessWidget {
+  const _TooOldScreen();
+  @override
+  Widget build(BuildContext context) {
+    return const Scaffold(
+      body: SafeArea(
+        child: Padding(
+          padding: EdgeInsets.all(24),
+          child: Center(
+            child: Column(
+              mainAxisAlignment: MainAxisAlignment.center,
+              children: [
+                Text(
+                  'Update required',
+                  style: TextStyle(fontSize: 24, fontWeight: FontWeight.w500),
+                ),
+                SizedBox(height: 12),
+                Text(
+                  'This client is too old for that Minstrel server. Install the latest build to continue.',
+                  textAlign: TextAlign.center,
+                ),
+              ],
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+}