import 'package:flutter/material.dart';

import '../data/models.dart';
import '../data/repository.dart';
import '../theme/reclaim_tokens.dart';

/// Status banner above the data screens.
///
/// Picks one of three voices by the active repository's mode:
///
///   demo       → orange T4: 'Demo-Daten · keine Rechtsberatung'
///                (MockRepository on, Beirat + Juristen-Pipeline
///                still missing)
///
///   hub-live   → petrol-signal: 'Live aus Hub' + hub label
///                (HubRepository connected, list() reads real
///                flow.completed events)
///
///   hub-down   → warm-warning: 'Hub nicht erreichbar — leere
///                Liste, prüfe Hub-Tab'
///                (HubRepository.connect timed out; fallback to
///                empty list rather than mocked data)
class ModeBanner extends StatelessWidget {
  const ModeBanner({super.key, required this.repository});

  final EvaluationRepository repository;

  @override
  Widget build(BuildContext context) {
    final t = Theme.of(context).textTheme;

    final (color, icon, message) = switch (repository.mode) {
      'hub-live' => (
        ReclaimColors.signal,
        Icons.bolt_outlined,
        'Live aus Hub · ${repository.hubLabel}. '
            'Werte stammen aus den flow.completed-Events des '
            'Ch∆In-Audit-Logs. Volljuristen-Approval-Kette ist '
            'in Phase 0 noch Selbst-Review — siehe „Recht".',
      ),
      'hub-down' => (
        ReclaimColors.harmWarm,
        Icons.signal_wifi_off,
        'Hub nicht erreichbar — leere Liste. Konfiguration prüfen '
            'unter „Hub". Bis dahin: kein Recl∆Im-Datenpunkt '
            'sichtbar.',
      ),
      _ => (
        ReclaimColors.tierT4,
        Icons.science_outlined,
        'Demo-Daten · KEINE Rechtsberatung. Alle Zahlen sind als '
            'T4 markiert (qualitatives Signal), bis NKR-/Verbands-'
            'Pipeline + Juristen-Approval laufen. Erläuterung der '
            'Stufen unter „Methodik", Disclaimer unter „Recht".',
      ),
    };

    return Container(
      width: double.infinity,
      padding: const EdgeInsets.symmetric(
        horizontal: ReclaimSpace.lg,
        vertical: ReclaimSpace.sm,
      ),
      decoration: BoxDecoration(
        color: color.withValues(alpha: 0.12),
        border: Border(
          bottom: BorderSide(color: color.withValues(alpha: 0.55)),
        ),
      ),
      child: Row(
        children: [
          Icon(icon, size: 18, color: color),
          const SizedBox(width: ReclaimSpace.sm),
          Expanded(
            child: Text(
              message,
              style: t.labelSmall?.copyWith(color: color),
            ),
          ),
        ],
      ),
    );
  }
}

/// Backwards-compat shim for pages that still import DemoBanner.
/// Resolves to the dynamic ModeBanner if a repository is passed,
/// otherwise stays demo-flavoured.
class DemoBanner extends StatelessWidget {
  const DemoBanner({super.key, this.repository});

  final EvaluationRepository? repository;

  @override
  Widget build(BuildContext context) {
    final repo = repository;
    if (repo != null) return ModeBanner(repository: repo);
    return const ModeBanner(repository: _DemoMockRepository());
  }
}

/// Internal sentinel so the bare-form DemoBanner() still renders
/// the orange demo voice even when no repository is plumbed in.
class _DemoMockRepository implements EvaluationRepository {
  const _DemoMockRepository();

  @override
  Future<List<Evaluation>> list() async => const [];

  @override
  Future<Evaluation?> byEli(String eli) async => null;

  @override
  String get mode => 'demo';

  @override
  String get hubLabel => '—';
}