import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:intl/intl.dart';
import '../../../core/api/client.dart';
import '../../../core/api/endpoints.dart';
import '../../../core/api/exceptions.dart';
import '../../../core/theme/app_theme.dart';
import '../../../models/admin.dart';
import '../../../models/tariff.dart';
import '../../../models/auth.dart';
import '../../../widgets/loading_indicator.dart';
import '../../../widgets/error_display.dart';
import '../../../widgets/empty_state.dart';

class AdminScreen extends ConsumerStatefulWidget {
  const AdminScreen({super.key});

  @override
  ConsumerState<AdminScreen> createState() => _AdminScreenState();
}

class _AdminScreenState extends ConsumerState<AdminScreen>
    with SingleTickerProviderStateMixin {
  late TabController _tabController;

  @override
  void initState() {
    super.initState();
    _tabController = TabController(length: 7, vsync: this);
  }

  @override
  void dispose() {
    _tabController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('Админ-панель'),
        bottom: TabBar(
          controller: _tabController,
          isScrollable: true,
          tabs: const [
            Tab(text: 'Статистика'),
            Tab(text: 'Пользователи'),
            Tab(text: 'Агенты'),
            Tab(text: 'Логи'),
            Tab(text: 'Тарифы'),
            Tab(text: 'Бот'),
            Tab(text: 'Сервисы'),
          ],
        ),
      ),
      body: TabBarView(
        controller: _tabController,
        children: const [
          _StatsTab(),
          _UsersTab(),
          _AgentsTab(),
          _LogsTab(),
          _TariffsTab(),
          _BotTab(),
          _ServicesTab(),
        ],
      ),
    );
  }
}

class _StatsTab extends ConsumerWidget {
  const _StatsTab();

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    return _FutureBuilder<AdminStats>(
      future: () async {
        final api = ref.read(apiClientProvider);
        final resp = await api.get(Endpoints.adminStats);
        return AdminStats.fromJson(resp.data as Map<String, dynamic>);
      },
      builder: (stats) => GridView.count(
        padding: const EdgeInsets.all(16),
        crossAxisCount: 2,
        mainAxisSpacing: 12,
        crossAxisSpacing: 12,
        childAspectRatio: 1.5,
        children: [
          _StatCard(label: 'Пользователи', value: '${stats.totalUsers}', icon: Icons.people),
          _StatCard(label: 'Идеи', value: '${stats.totalIdeas}', icon: Icons.lightbulb),
          _StatCard(label: 'Голосовые сессии', value: '${stats.totalVoiceSessions}', icon: Icons.mic),
          _StatCard(label: 'Раб. пространства', value: '${stats.totalWorkspaces}', icon: Icons.workspaces),
          _StatCard(label: 'Активные агенты', value: '${stats.activeAgents}', icon: Icons.smart_toy),
          _StatCard(label: 'Уведомления', value: '${stats.totalNotifications}', icon: Icons.notifications),
        ],
      ),
    );
  }
}

class _StatCard extends StatelessWidget {
  final String label;
  final String value;
  final IconData icon;

  const _StatCard({
    required this.label,
    required this.value,
    required this.icon,
  });

  @override
  Widget build(BuildContext context) {
    return Card(
      child: Padding(
        padding: const EdgeInsets.all(16),
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Icon(icon, color: VoIdeaColors.primary, size: 28),
            const SizedBox(height: 8),
            Text(value,
                style: Theme.of(context).textTheme.headlineSmall?.copyWith(
                      fontWeight: FontWeight.bold,
                    )),
            Text(label,
                style: const TextStyle(fontSize: 12, color: VoIdeaColors.muted)),
          ],
        ),
      ),
    );
  }
}

class _UsersTab extends ConsumerWidget {
  const _UsersTab();

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    return _FutureBuilder<List<User>>(
      future: () async {
        final api = ref.read(apiClientProvider);
        final resp = await api.get(Endpoints.adminUsers);
        return (resp.data as List<dynamic>)
            .map((e) => User.fromJson(e as Map<String, dynamic>))
            .toList();
      },
      builder: (users) => ListView.builder(
        padding: const EdgeInsets.all(16),
        itemCount: users.length,
        itemBuilder: (_, i) {
          final u = users[i];
          return Card(
            margin: const EdgeInsets.only(bottom: 8),
            child: ListTile(
              leading: CircleAvatar(
                backgroundColor: VoIdeaColors.primary.withOpacity(0.1),
                child: Text(u.name.isNotEmpty ? u.name[0].toUpperCase() : '?',
                    style: const TextStyle(color: VoIdeaColors.primary)),
              ),
              title: Text(u.name),
              subtitle: Text('${u.email} · ${DateFormat('d MMM yyyy').format(u.createdAt)}',
                  style: const TextStyle(fontSize: 12)),
              trailing: Row(
                mainAxisSize: MainAxisSize.min,
                children: [
                  if (u.isAdmin)
                    const Chip(label: Text('Admin', style: TextStyle(fontSize: 10))),
                  if (u.isTwoFactorEnabled)
                    const Padding(
                      padding: EdgeInsets.only(left: 4),
                      child: Icon(Icons.security, size: 16, color: VoIdeaColors.success),
                    ),
                ],
              ),
            ),
          );
        },
      ),
    );
  }
}

class _AgentsTab extends ConsumerWidget {
  const _AgentsTab();

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    return _FutureBuilder<List<AgentConfig>>(
      future: () async {
        final api = ref.read(apiClientProvider);
        final resp = await api.get(Endpoints.adminAgents);
        return (resp.data as List<dynamic>)
            .map((e) => AgentConfig.fromJson(e as Map<String, dynamic>))
            .toList();
      },
      builder: (agents) => Column(
        children: [
          Padding(
            padding: const EdgeInsets.all(16),
            child: Row(
              children: [
                Expanded(
                  child: ElevatedButton.icon(
                    onPressed: () => _runAllAgents(ref),
                    icon: const Icon(Icons.play_arrow),
                    label: const Text('Запустить всех'),
                  ),
                ),
              ],
            ),
          ),
          Expanded(
            child: ListView.builder(
              padding: const EdgeInsets.symmetric(horizontal: 16),
              itemCount: agents.length,
              itemBuilder: (_, i) {
                final agent = agents[i];
                return Card(
                  margin: const EdgeInsets.only(bottom: 8),
                  child: ExpansionTile(
                    leading: Icon(
                      agent.isActive ? Icons.smart_toy : Icons.smart_toy_outlined,
                      color: agent.isActive ? VoIdeaColors.success : VoIdeaColors.muted,
                    ),
                    title: Text(agent.name),
                    subtitle: Text(agent.description, maxLines: 1,
                        overflow: TextOverflow.ellipsis),
                    trailing: Row(
                      mainAxisSize: MainAxisSize.min,
                      children: [
                        IconButton(
                          icon: const Icon(Icons.play_arrow, size: 20),
                          onPressed: () => _runAgent(ref, agent.name),
                        ),
                        const Icon(Icons.expand_more),
                      ],
                    ),
                    children: [
                      Padding(
                        padding: const EdgeInsets.all(16),
                        child: Column(
                          crossAxisAlignment: CrossAxisAlignment.start,
                          children: [
                            Text('Расписание: ${agent.schedule}',
                                style: const TextStyle(fontSize: 12)),
                            const SizedBox(height: 8),
                            Text('Активен: ${agent.isActive ? "Да" : "Нет"}',
                                style: const TextStyle(fontSize: 12)),
                            const SizedBox(height: 8),
                            Text('Конфиг: ${agent.config.toString()}',
                                style: const TextStyle(fontSize: 12)),
                          ],
                        ),
                      ),
                    ],
                  ),
                );
              },
            ),
          ),
        ],
      ),
    );
  }

  void _runAgent(WidgetRef ref, String name) async {
    try {
      final api = ref.read(apiClientProvider);
      await api.post(Endpoints.adminAgentRun(name));
    } catch (_) {}
  }

  void _runAllAgents(WidgetRef ref) async {
    try {
      final api = ref.read(apiClientProvider);
      await api.post(Endpoints.adminAgentsRunAll);
    } catch (_) {}
  }
}

class _LogsTab extends ConsumerWidget {
  const _LogsTab();

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    return _FutureBuilder<List<LogEntry>>(
      future: () async {
        final api = ref.read(apiClientProvider);
        final resp = await api.get(Endpoints.adminLogs);
        return (resp.data as List<dynamic>)
            .map((e) => LogEntry.fromJson(e as Map<String, dynamic>))
            .toList();
      },
      builder: (logs) => ListView.builder(
        padding: const EdgeInsets.all(16),
        itemCount: logs.length,
        itemBuilder: (_, i) {
          final log = logs[i];
          final color = log.level == 'ERROR'
              ? VoIdeaColors.error
              : log.level == 'WARNING'
                  ? VoIdeaColors.warning
                  : VoIdeaColors.muted;
          return Card(
            margin: const EdgeInsets.only(bottom: 4),
            child: ListTile(
              dense: true,
              leading: Container(
                width: 8,
                height: 8,
                decoration: BoxDecoration(color: color, shape: BoxShape.circle),
              ),
              title: Text(log.message,
                  maxLines: 1, overflow: TextOverflow.ellipsis,
                  style: const TextStyle(fontSize: 13)),
              subtitle: Row(
                children: [
                  Text(log.level, style: TextStyle(fontSize: 11, color: color)),
                  const SizedBox(width: 8),
                  if (log.source != null)
                    Text(log.source!,
                        style: const TextStyle(fontSize: 11, color: VoIdeaColors.muted)),
                  const Spacer(),
                  Text(DateFormat('HH:mm:ss').format(log.createdAt),
                      style: const TextStyle(fontSize: 11, color: VoIdeaColors.muted)),
                ],
              ),
            ),
          );
        },
      ),
    );
  }
}

class _TariffsTab extends ConsumerWidget {
  const _TariffsTab();

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    return _FutureBuilder<List<Tariff>>(
      future: () async {
        final api = ref.read(apiClientProvider);
        final resp = await api.get(Endpoints.adminTariffs);
        return (resp.data as List<dynamic>)
            .map((e) => Tariff.fromJson(e as Map<String, dynamic>))
            .toList();
      },
      builder: (tariffs) => ListView.builder(
        padding: const EdgeInsets.all(16),
        itemCount: tariffs.length,
        itemBuilder: (_, i) {
          final t = tariffs[i];
          return Card(
            margin: const EdgeInsets.only(bottom: 12),
            child: Padding(
              padding: const EdgeInsets.all(16),
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  Row(
                    children: [
                      Text(t.name,
                          style: Theme.of(context).textTheme.titleMedium?.copyWith(
                                fontWeight: FontWeight.w600,
                              )),
                      const Spacer(),
                      Text('${t.price} ${t.currency}/мес',
                          style: TextStyle(
                              color: VoIdeaColors.primary,
                              fontWeight: FontWeight.w600)),
                    ],
                  ),
                  const SizedBox(height: 8),
                  ...t.features.entries.map((e) => Padding(
                        padding: const EdgeInsets.only(bottom: 4),
                        child: Row(
                          children: [
                            Icon(Icons.check, size: 14, color: VoIdeaColors.success),
                            const SizedBox(width: 8),
                            Text('${e.key}: ${e.value}',
                                style: const TextStyle(fontSize: 13)),
                          ],
                        ),
                      )),
                ],
              ),
            ),
          );
        },
      ),
    );
  }
}

class _BotTab extends ConsumerWidget {
  const _BotTab();

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    return _FutureBuilder<List<BotCommand>>(
      future: () async {
        final api = ref.read(apiClientProvider);
        final resp = await api.get(Endpoints.adminBotCommands);
        return (resp.data as List<dynamic>)
            .map((e) => BotCommand.fromJson(e as Map<String, dynamic>))
            .toList();
      },
      builder: (commands) => ListView.builder(
        padding: const EdgeInsets.all(16),
        itemCount: commands.length,
        itemBuilder: (_, i) {
          final cmd = commands[i];
          return Card(
            margin: const EdgeInsets.only(bottom: 8),
            child: ListTile(
              leading: Icon(
                cmd.isEnabled ? Icons.check_circle : Icons.cancel,
                color: cmd.isEnabled ? VoIdeaColors.success : VoIdeaColors.error,
              ),
              title: Text('/${cmd.command}'),
              subtitle: Text(cmd.description, maxLines: 1,
                  overflow: TextOverflow.ellipsis),
              trailing: Switch(
                value: cmd.isEnabled,
                onChanged: (v) => _toggleCommand(ref, cmd.id, v),
              ),
            ),
          );
        },
      ),
    );
  }

  void _toggleCommand(WidgetRef ref, String id, bool enabled) async {
    try {
      final api = ref.read(apiClientProvider);
      await api.patch('${Endpoints.adminBotCommands}/$id', data: {
        'is_enabled': enabled,
      });
    } catch (_) {}
  }
}

class _ServicesTab extends ConsumerWidget {
  const _ServicesTab();

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    return _FutureBuilder<HealthStatus>(
      future: () async {
        final api = ref.read(apiClientProvider);
        final resp = await api.get(Endpoints.adminHealth);
        return HealthStatus.fromJson(resp.data as Map<String, dynamic>);
      },
      builder: (health) => ListView(
        padding: const EdgeInsets.all(16),
        children: [
          Card(
            child: Padding(
              padding: const EdgeInsets.all(16),
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  Row(
                    children: [
                      Icon(
                        health.status == 'ok'
                            ? Icons.check_circle
                            : Icons.error,
                        color: health.status == 'ok'
                            ? VoIdeaColors.success
                            : VoIdeaColors.error,
                      ),
                      const SizedBox(width: 8),
                      Text('Статус: ${health.status}',
                          style: Theme.of(context).textTheme.titleMedium),
                    ],
                  ),
                  const SizedBox(height: 12),
                  Text('Версия: ${health.version}',
                      style: const TextStyle(fontSize: 13)),
                  const SizedBox(height: 4),
                  Text('Uptime: ${health.uptimeSeconds.toStringAsFixed(0)}с',
                      style: const TextStyle(fontSize: 13)),
                ],
              ),
            ),
          ),
          const SizedBox(height: 16),
          const Text('Сервисы',
              style: TextStyle(fontWeight: FontWeight.w600, fontSize: 16)),
          const SizedBox(height: 8),
          ...health.services.entries.map((e) => Card(
                margin: const EdgeInsets.only(bottom: 8),
                child: ListTile(
                  leading: Icon(
                    e.value == 'ok' || e.value == true
                        ? Icons.check_circle
                        : Icons.error,
                    color: e.value == 'ok' || e.value == true
                        ? VoIdeaColors.success
                        : VoIdeaColors.error,
                    size: 20,
                  ),
                  title: Text(e.key),
                  subtitle: Text('${e.value}'),
                ),
              )),
        ],
      ),
    );
  }
}

class _FutureBuilder<T> extends StatelessWidget {
  final Future<T> Function() future;
  final Widget Function(T data) builder;

  const _FutureBuilder({required this.future, required this.builder});

  @override
  Widget build(BuildContext context) {
    return FutureBuilder<T>(
      future: future(),
      builder: (ctx, snapshot) {
        if (snapshot.connectionState == ConnectionState.waiting) {
          return const LoadingIndicator();
        }
        if (snapshot.hasError) {
          return ErrorDisplay(message: snapshot.error.toString());
        }
        if (!snapshot.hasData) {
          return const EmptyState(
              icon: Icons.info_outline, title: 'Нет данных');
        }
        return builder(snapshot.data!);
      },
    );
  }
}