import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';

import '../features/provisioning/models/wiz_provisioning_environment.dart';
import '../features/provisioning/models/wiz_provisioning_state.dart';
import '../features/provisioning/providers/wiz_provisioning_providers.dart';

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

  @override
  ConsumerState<WizProvisioningScreen> createState() =>
      _WizProvisioningScreenState();
}

class _WizProvisioningScreenState extends ConsumerState<WizProvisioningScreen>
    with WidgetsBindingObserver {
  final _formKey = GlobalKey<FormState>();
  final _ssidCtrl = TextEditingController();
  final _bssidCtrl = TextEditingController();
  final _passwordCtrl = TextEditingController();

  bool _ssidTouched = false;
  bool _bssidTouched = false;

  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addObserver(this);
    Future<void>.microtask(
      () => ref.read(wizProvisioningProvider.notifier).initialize(),
    );
  }

  @override
  void dispose() {
    WidgetsBinding.instance.removeObserver(this);
    ref
        .read(wizProvisioningProvider.notifier)
        .cancelProvisioning(keepCurrentState: false);
    ref.invalidate(wizProvisioningProvider);
    _ssidCtrl.dispose();
    _bssidCtrl.dispose();
    _passwordCtrl.dispose();
    super.dispose();
  }

  @override
  void didChangeAppLifecycleState(AppLifecycleState state) {
    if (state == AppLifecycleState.resumed) {
      Future<void>.microtask(
        () => ref.read(wizProvisioningProvider.notifier).initialize(),
      );
    }
  }

  @override
  Widget build(BuildContext context) {
    final provisioningState = ref.watch(wizProvisioningProvider);
    _syncControllers(provisioningState.environment);
    final bottomInset = MediaQuery.paddingOf(context).bottom;

    final environment = provisioningState.environment;
    final failure = provisioningState.failure;
    final canRequestPermissions =
        !environment.permissionsGranted && environment.permissionRequestable;
    final canOpenAppSettings =
        environment.requiresAppSettings && environment.appSettingsSupported;
    final needsWifiSettings =
        !environment.connectedToWifi && environment.wifiSettingsSupported;

    return Scaffold(
      appBar: AppBar(title: const Text('ПОДКЛЮЧЕНИЕ WIZ')),
      body: SafeArea(
        top: false,
        bottom: true,
        child: RefreshIndicator(
          color: Colors.deepOrange,
          onRefresh: () =>
              ref.read(wizProvisioningProvider.notifier).initialize(),
          child: ListView(
            padding: EdgeInsets.fromLTRB(16, 16, 16, bottomInset + 24),
            children: [
              _SectionCard(
                title: 'Что делает мастер',
                child: const Text(
                  'Эта версия использует smart pairing: телефон остаётся в домашней Wi-Fi сети и передаёт её настройки новой лампе. Это Android-only поток и он лучше всего работает, когда телефон уже сидит на 2.4 GHz.',
                  style: TextStyle(color: Colors.white70),
                ),
              ),
              _SectionCard(
                title: 'Активный дом',
                child: Text(
                  provisioningState.activeHomeName == null
                      ? 'Не выбран'
                      : provisioningState.activeHomeName!,
                  style: TextStyle(
                    color: provisioningState.activeHomeName == null
                        ? Colors.redAccent
                        : Colors.white,
                    fontWeight: FontWeight.w600,
                  ),
                ),
              ),
              _SectionCard(
                title: 'Окружение',
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    _InfoRow(
                      label: 'Платформа',
                      value: environment.isAndroid
                          ? 'Android ${environment.androidApiLevel ?? '?'}'
                          : environment.platform,
                    ),
                    _InfoRow(
                      label: 'Разрешения',
                      value: _permissionStatusLabel(
                        environment.permissionStatus,
                      ),
                    ),
                    _InfoRow(
                      label: 'Wi-Fi',
                      value: environment.connectedToWifi
                          ? (environment.ssid ?? 'Подключено')
                          : 'Нет подключения',
                    ),
                    _InfoRow(
                      label: 'BSSID',
                      value: environment.bssid ?? 'Не удалось определить',
                    ),
                    _InfoRow(
                      label: 'Диапазон',
                      value: environment.frequencyMhz == null
                          ? 'Неизвестно'
                          : '${environment.frequencyMhz} MHz',
                    ),
                    if (environment.isLikelyOn5Ghz)
                      const Padding(
                        padding: EdgeInsets.only(top: 8),
                        child: Text(
                          'Сейчас похоже активен 5 GHz. Для WiZ лучше заранее переключиться на 2.4 GHz.',
                          style: TextStyle(color: Colors.amberAccent),
                        ),
                      ),
                    if (!environment.locationServicesEnabled)
                      const Padding(
                        padding: EdgeInsets.only(top: 8),
                        child: Text(
                          'На Android системная геолокация должна быть включена, иначе SSID/BSSID часто скрываются системой.',
                          style: TextStyle(color: Colors.amberAccent),
                        ),
                      ),
                  ],
                ),
              ),
              if (failure != null)
                _SectionCard(
                  title: 'Проблема',
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Text(
                        failure.message,
                        style: const TextStyle(color: Colors.redAccent),
                      ),
                      if (failure.details != null) ...[
                        const SizedBox(height: 8),
                        Text(
                          failure.details!,
                          style: const TextStyle(color: Colors.white54),
                        ),
                      ],
                    ],
                  ),
                ),
              if (provisioningState.notice != null)
                _SectionCard(
                  title: 'Примечание',
                  child: Text(
                    provisioningState.notice!,
                    style: const TextStyle(color: Colors.white70),
                  ),
                ),
              _SectionCard(
                title: 'Шаги перед стартом',
                child: const Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Text(
                      '1. Убедитесь, что телефон подключён к домашней 2.4 GHz Wi-Fi.',
                      style: TextStyle(color: Colors.white70),
                    ),
                    SizedBox(height: 6),
                    Text(
                      '2. Переведите лампу в pairing mode: если нужно, несколько раз выключите и включите питание до пульсации.',
                      style: TextStyle(color: Colors.white70),
                    ),
                    SizedBox(height: 6),
                    Text(
                      '3. Держите телефон рядом с лампой и не сворачивайте приложение до конца pairing.',
                      style: TextStyle(color: Colors.white70),
                    ),
                  ],
                ),
              ),
              _SectionCard(
                title: 'Домашняя Wi-Fi',
                child: Form(
                  key: _formKey,
                  autovalidateMode: AutovalidateMode.onUserInteraction,
                  child: Column(
                    children: [
                      TextFormField(
                        controller: _ssidCtrl,
                        decoration: const InputDecoration(
                          labelText: 'SSID',
                          hintText: 'Например: Home-2G',
                          prefixIcon: Icon(Icons.wifi),
                        ),
                        onChanged: (_) => _ssidTouched = true,
                        validator: (value) {
                          if ((value?.trim().isEmpty ?? true)) {
                            return 'Укажите SSID';
                          }
                          return null;
                        },
                      ),
                      const SizedBox(height: 12),
                      TextFormField(
                        controller: _bssidCtrl,
                        decoration: const InputDecoration(
                          labelText: 'BSSID (опционально)',
                          hintText: 'aa:bb:cc:dd:ee:ff',
                          prefixIcon: Icon(Icons.router_outlined),
                        ),
                        onChanged: (_) => _bssidTouched = true,
                      ),
                      const SizedBox(height: 12),
                      TextFormField(
                        controller: _passwordCtrl,
                        decoration: const InputDecoration(
                          labelText: 'Пароль Wi-Fi',
                          hintText: 'Оставьте пустым для открытой сети',
                          prefixIcon: Icon(Icons.key),
                        ),
                        obscureText: true,
                      ),
                    ],
                  ),
                ),
              ),
              _ActionSection(
                state: provisioningState,
                canRequestPermissions: canRequestPermissions,
                canOpenAppSettings: canOpenAppSettings,
                needsWifiSettings: needsWifiSettings,
                onRequestPermissions: () => ref
                    .read(wizProvisioningProvider.notifier)
                    .requestPermissions(),
                onOpenAppSettings: () => ref
                    .read(wizProvisioningProvider.notifier)
                    .openAppSettings(),
                onOpenWifiSettings: () => ref
                    .read(wizProvisioningProvider.notifier)
                    .openWifiSettings(),
                onRefresh: () =>
                    ref.read(wizProvisioningProvider.notifier).initialize(),
                onStart: _startProvisioning,
                onCancel: () => ref
                    .read(wizProvisioningProvider.notifier)
                    .cancelProvisioning(),
              ),
              if (provisioningState.provisionedDevices.isNotEmpty)
                _SectionCard(
                  title: 'Ответившие устройства',
                  child: Column(
                    children: [
                      for (final device in provisioningState.provisionedDevices)
                        ListTile(
                          dense: true,
                          contentPadding: EdgeInsets.zero,
                          leading: const Icon(
                            Icons.lightbulb_outline,
                            color: Colors.deepOrange,
                          ),
                          title: Text(device.bssid),
                          subtitle: device.ipAddress == null
                              ? null
                              : Text(device.ipAddress!),
                        ),
                    ],
                  ),
                ),
              if (provisioningState.rescanSummary != null)
                _SectionCard(
                  title: 'Результат discovery',
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      _InfoRow(
                        label: 'Найдено',
                        value: '${provisioningState.rescanSummary!.found}',
                      ),
                      _InfoRow(
                        label: 'Добавлено',
                        value: '${provisioningState.rescanSummary!.added}',
                      ),
                      _InfoRow(
                        label: 'Обновлено',
                        value: '${provisioningState.rescanSummary!.updated}',
                      ),
                      _InfoRow(
                        label: 'Онлайн',
                        value: '${provisioningState.rescanSummary!.online}',
                      ),
                    ],
                  ),
                ),
              if (provisioningState.timeline.isNotEmpty)
                _SectionCard(
                  title: 'Ход выполнения',
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      for (final event in provisioningState.timeline)
                        Padding(
                          padding: const EdgeInsets.only(bottom: 8),
                          child: Text(
                            '• $event',
                            style: const TextStyle(color: Colors.white60),
                          ),
                        ),
                    ],
                  ),
                ),
            ],
          ),
        ),
      ),
    );
  }

  void _syncControllers(WizProvisioningEnvironment environment) {
    if (!_ssidTouched &&
        environment.ssid != null &&
        environment.ssid != _ssidCtrl.text) {
      _ssidCtrl.text = environment.ssid!;
    }

    if (!_bssidTouched &&
        environment.bssid != null &&
        environment.bssid != _bssidCtrl.text) {
      _bssidCtrl.text = environment.bssid!;
    }
  }

  Future<void> _startProvisioning() async {
    if (!_formKey.currentState!.validate()) {
      return;
    }

    await ref
        .read(wizProvisioningProvider.notifier)
        .startProvisioning(
          ssid: _ssidCtrl.text,
          password: _passwordCtrl.text,
          bssid: _bssidCtrl.text.trim().isEmpty ? null : _bssidCtrl.text,
        );
  }

  String _permissionStatusLabel(WizProvisioningPermissionStatus status) {
    switch (status) {
      case WizProvisioningPermissionStatus.granted:
        return 'Выданы';
      case WizProvisioningPermissionStatus.requestable:
        return 'Нужно запросить';
      case WizProvisioningPermissionStatus.settingsRequired:
        return 'Нужно открыть настройки приложения';
    }
  }
}

class _ActionSection extends StatelessWidget {
  final WizProvisioningState state;
  final bool canRequestPermissions;
  final bool canOpenAppSettings;
  final bool needsWifiSettings;
  final VoidCallback onRequestPermissions;
  final VoidCallback onOpenAppSettings;
  final VoidCallback onOpenWifiSettings;
  final VoidCallback onRefresh;
  final VoidCallback onStart;
  final VoidCallback onCancel;

  const _ActionSection({
    required this.state,
    required this.canRequestPermissions,
    required this.canOpenAppSettings,
    required this.needsWifiSettings,
    required this.onRequestPermissions,
    required this.onOpenAppSettings,
    required this.onOpenWifiSettings,
    required this.onRefresh,
    required this.onStart,
    required this.onCancel,
  });

  @override
  Widget build(BuildContext context) {
    final canStartProvisioning =
        !state.isBusy &&
        state.activeHomeName != null &&
        state.environment.permissionsGranted &&
        state.environment.locationServicesEnabled &&
        state.environment.connectedToWifi &&
        state.status != WizProvisioningStatus.unsupported;

    return _SectionCard(
      title: 'Действия',
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.stretch,
        children: [
          if (state.isBusy)
            const Padding(
              padding: EdgeInsets.only(bottom: 12),
              child: LinearProgressIndicator(color: Colors.deepOrange),
            ),
          FilledButton.icon(
            onPressed: canStartProvisioning ? onStart : null,
            icon: const Icon(Icons.flash_on),
            label: Text(
              state.status == WizProvisioningStatus.success
                  ? 'Повторить pairing'
                  : 'Запустить smart pairing',
            ),
          ),
          const SizedBox(height: 8),
          OutlinedButton.icon(
            onPressed: state.isBusy ? onCancel : onRefresh,
            icon: Icon(
              state.isBusy ? Icons.stop_circle_outlined : Icons.refresh,
            ),
            label: Text(state.isBusy ? 'Остановить' : 'Переобновить окружение'),
          ),
          if (canRequestPermissions) ...[
            const SizedBox(height: 8),
            OutlinedButton.icon(
              onPressed: state.isBusy ? null : onRequestPermissions,
              icon: const Icon(Icons.privacy_tip_outlined),
              label: const Text('Выдать разрешения'),
            ),
          ],
          if (canOpenAppSettings) ...[
            const SizedBox(height: 8),
            OutlinedButton.icon(
              onPressed: state.isBusy ? null : onOpenAppSettings,
              icon: const Icon(Icons.settings_applications_outlined),
              label: const Text('Открыть настройки приложения'),
            ),
          ],
          if (needsWifiSettings) ...[
            const SizedBox(height: 8),
            OutlinedButton.icon(
              onPressed: state.isBusy ? null : onOpenWifiSettings,
              icon: const Icon(Icons.wifi_find_outlined),
              label: const Text('Открыть настройки Wi-Fi'),
            ),
          ],
        ],
      ),
    );
  }
}

class _SectionCard extends StatelessWidget {
  final String title;
  final Widget child;

  const _SectionCard({required this.title, required this.child});

  @override
  Widget build(BuildContext context) {
    return Card(
      margin: const EdgeInsets.only(bottom: 12),
      child: Padding(
        padding: const EdgeInsets.all(16),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Text(
              title,
              style: const TextStyle(
                fontWeight: FontWeight.bold,
                color: Colors.white,
              ),
            ),
            const SizedBox(height: 12),
            child,
          ],
        ),
      ),
    );
  }
}

class _InfoRow extends StatelessWidget {
  final String label;
  final String value;

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

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.only(bottom: 8),
      child: Row(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          SizedBox(
            width: 112,
            child: Text(label, style: const TextStyle(color: Colors.white38)),
          ),
          Expanded(
            child: Text(value, style: const TextStyle(color: Colors.white70)),
          ),
        ],
      ),
    );
  }
}