part of '../chat_view.dart';

// Shows a slim banner when the client loses its connection to the homeserver.
// Debounced so brief transient sync errors don't flicker a banner.
class _ConnectionBanner extends ConsumerStatefulWidget {
  const _ConnectionBanner();
  @override
  ConsumerState<_ConnectionBanner> createState() => _ConnectionBannerState();
}

class _ConnectionBannerState extends ConsumerState<_ConnectionBanner> {
  StreamSubscription? _sub;
  Timer? _debounce;
  bool _lost = false;

  @override
  void initState() {
    super.initState();
    _attach();
  }

  Future<void> _attach() async {
    try {
      final client = await ref.read(matrixClientProvider.future);
      _sub = client.onSyncStatus.stream.listen((s) {
        if (s.status == SyncStatus.error) {
          // Only surface after the error persists a few seconds.
          _debounce ??= Timer(const Duration(seconds: 4), () {
            _debounce = null;
            if (mounted) setState(() => _lost = true);
          });
        } else if (s.status == SyncStatus.finished ||
            s.status == SyncStatus.processing) {
          _debounce?.cancel();
          _debounce = null;
          if (_lost && mounted) setState(() => _lost = false);
        }
      });
    } catch (_) {}
  }

  @override
  void dispose() {
    _sub?.cancel();
    _debounce?.cancel();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final pt = PyramidTheme.of(context);
    return AnimatedSize(
      duration: const Duration(milliseconds: 200),
      curve: Curves.easeOut,
      alignment: Alignment.topCenter,
      child: _lost
          ? Container(
              width: double.infinity,
              color: pt.danger.withAlpha(36),
              padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 6),
              child: Row(
                mainAxisAlignment: MainAxisAlignment.center,
                children: [
                  Icon(Icons.cloud_off_rounded, size: 14, color: pt.danger),
                  const SizedBox(width: 8),
                  Flexible(
                    child: Text(
                      'Keine Verbindung zum Server – Wiederverbindung läuft…',
                      style: TextStyle(color: pt.danger, fontSize: 12, fontWeight: FontWeight.w500),
                      maxLines: 1,
                      overflow: TextOverflow.ellipsis,
                    ),
                  ),
                ],
              ),
            )
          : const SizedBox.shrink(),
    );
  }
}