import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import '../l10n/app_localizations.dart';
import '../../domain/entities/server_config.dart';
import '../bloc/settings_bloc.dart';
import '../bloc/settings_event.dart';
import '../bloc/settings_state.dart';

class SettingsPage extends StatelessWidget {
  const SettingsPage({super.key});

  @override
  Widget build(BuildContext context) {
    return BlocBuilder<SettingsBloc, SettingsState>(
      builder: (context, state) {
        return state.when(
          initial: () => const Center(child: CircularProgressIndicator()),
          loading: () => const Center(child: CircularProgressIndicator()),
          loaded: (apiUrl, serverConfig, languageCode, error) => _SettingsContent(
            apiUrl: apiUrl,
            serverConfig: serverConfig,
            languageCode: languageCode,
            error: error,
          ),
          error: (message) => Center(child: Text(message)),
        );
      },
    );
  }
}

class _SettingsContent extends StatelessWidget {
  final String apiUrl;
  final ServerConfig? serverConfig;
  final String languageCode;
  final String? error;

  const _SettingsContent({
    required this.apiUrl,
    required this.serverConfig,
    required this.languageCode,
    this.error,
  });

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context)!;

    return ListView(
      children: [
        _SectionHeader(title: l10n.serverSettings),
        _ApiUrlTile(
          apiUrl: apiUrl,
          onSave: (url) {
            context.read<SettingsBloc>().add(SettingsApiUrlSaved(url));
          },
        ),
        const Divider(),

        _SectionHeader(title: l10n.language),
        _LanguageTile(
          currentCode: languageCode,
          onChanged: (code) {
            context.read<SettingsBloc>().add(SettingsLanguageChanged(code));
          },
        ),
        const Divider(),

        if (serverConfig != null) ...[
          _SectionHeader(title: l10n.serverConfig),
          _ConfigModuleCard(
            title: l10n.system,
            icon: Icons.computer,
            children: [
              _ConfigItem(label: l10n.domainUrl, value: serverConfig!.system.domainUrl),
              _ConfigItem(label: l10n.enableRegistration, value: serverConfig!.system.enableRegistration ? l10n.enabled : l10n.disabled),
            ],
          ),
          _ConfigModuleCard(
            title: l10n.messages,
            icon: Icons.message,
            children: [
              _ConfigItem(label: l10n.enabled, value: serverConfig!.messages.allowMedia ? l10n.enabled : l10n.disabled),
              _ConfigItem(label: 'Max media size', value: '${(serverConfig!.messages.maxMediaSizeBytes / 1024 / 1024).toStringAsFixed(1)} MB'),
            ],
          ),
          _ConfigModuleCard(
            title: l10n.calls,
            icon: Icons.call,
            children: [
              _ConfigItem(label: l10n.enabled, value: serverConfig!.webRtc.enabled ? l10n.enabled : l10n.disabled),
              _ConfigItem(label: 'Voice calls', value: serverConfig!.webRtc.enableVoiceCalls ? l10n.enabled : l10n.disabled),
              _ConfigItem(label: 'Video calls', value: serverConfig!.webRtc.enableVideoCalls ? l10n.enabled : l10n.disabled),
            ],
          ),
          _ConfigModuleCard(
            title: l10n.stories,
            icon: Icons.auto_stories,
            children: [
              _ConfigItem(label: l10n.enabled, value: serverConfig!.stories.enabled ? l10n.enabled : l10n.disabled),
              _ConfigItem(label: 'Lifetime', value: '${serverConfig!.stories.storyLifetimeHours}h'),
            ],
          ),
          _ConfigModuleCard(
            title: l10n.chatsModule,
            icon: Icons.chat_bubble,
            children: [
              _ConfigItem(label: 'Groups', value: serverConfig!.chats.supportGroups ? l10n.enabled : l10n.disabled),
              _ConfigItem(label: 'Max participants', value: '${serverConfig!.chats.maxGroupParticipants}'),
            ],
          ),
          if (serverConfig!.federation.enabled)
            _ConfigModuleCard(
              title: l10n.federation,
              icon: Icons.public,
              children: [
                _ConfigItem(label: 'Description', value: serverConfig!.federation.serverDescription),
              ],
            ),
          const Divider(),
        ],

        if (serverConfig == null)
          ListTile(
            leading: const Icon(Icons.refresh),
            title: Text(l10n.retry),
            onTap: () {
              context.read<SettingsBloc>().add(const SettingsRefreshConfig());
            },
          ),

        _SectionHeader(title: l10n.settings),
        _SettingsTile(
          icon: Icons.notifications_outlined,
          title: l10n.notifications,
          onTap: () {},
        ),
        _SettingsTile(
          icon: Icons.security,
          title: l10n.privacy,
          onTap: () {},
        ),
        _SettingsTile(
          icon: Icons.volume_up,
          title: l10n.soundsAndVibration,
          onTap: () {},
        ),
        _SettingsTile(
          icon: Icons.storage,
          title: l10n.dataAndStorage,
          onTap: () {},
        ),
        const Divider(),

        _SettingsTile(
          icon: Icons.info_outline,
          title: l10n.aboutApp,
          subtitle: '${l10n.version} 1.0.0',
          onTap: () {},
        ),
        _SettingsTile(
          icon: Icons.help_outline,
          title: l10n.help,
          onTap: () {},
        ),
        const Divider(),

        Padding(
          padding: const EdgeInsets.all(16),
          child: OutlinedButton(
            onPressed: () {},
            style: OutlinedButton.styleFrom(
              foregroundColor: Colors.red,
              side: const BorderSide(color: Colors.red),
            ),
            child: Padding(
              padding: const EdgeInsets.symmetric(vertical: 12),
              child: Text(l10n.logout),
            ),
          ),
        ),
      ],
    );
  }
}

class _SectionHeader extends StatelessWidget {
  final String title;

  const _SectionHeader({required this.title});

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.fromLTRB(16, 16, 16, 8),
      child: Text(
        title.toUpperCase(),
        style: TextStyle(
          fontSize: 13,
          fontWeight: FontWeight.w600,
          color: Theme.of(context).colorScheme.primary,
          letterSpacing: 0.5,
        ),
      ),
    );
  }
}

class _ApiUrlTile extends StatefulWidget {
  final String apiUrl;
  final ValueChanged<String> onSave;

  const _ApiUrlTile({
    required this.apiUrl,
    required this.onSave,
  });

  @override
  State<_ApiUrlTile> createState() => _ApiUrlTileState();
}

class _ApiUrlTileState extends State<_ApiUrlTile> {
  late final TextEditingController _controller;
  bool _isEditing = false;

  @override
  void initState() {
    super.initState();
    _controller = TextEditingController(text: widget.apiUrl);
  }

  @override
  void didUpdateWidget(covariant _ApiUrlTile oldWidget) {
    super.didUpdateWidget(oldWidget);
    if (oldWidget.apiUrl != widget.apiUrl) {
      _controller.text = widget.apiUrl;
    }
  }

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

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context)!;

    if (_isEditing) {
      return Padding(
        padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
        child: Row(
          children: [
            Expanded(
              child: TextField(
                controller: _controller,
                decoration: InputDecoration(
                  labelText: l10n.apiUrl,
                  hintText: l10n.apiUrlHint,
                  border: const OutlineInputBorder(),
                  contentPadding: const EdgeInsets.symmetric(horizontal: 12, vertical: 8),
                ),
                keyboardType: TextInputType.url,
              ),
            ),
            const SizedBox(width: 8),
            IconButton(
              icon: const Icon(Icons.check, color: Colors.green),
              onPressed: () {
                widget.onSave(_controller.text.trim());
                setState(() => _isEditing = false);
              },
            ),
            IconButton(
              icon: const Icon(Icons.close, color: Colors.red),
              onPressed: () {
                _controller.text = widget.apiUrl;
                setState(() => _isEditing = false);
              },
            ),
          ],
        ),
      );
    }

    return ListTile(
      leading: const Icon(Icons.link),
      title: Text(l10n.apiUrl),
      subtitle: Text(
        widget.apiUrl.isEmpty ? l10n.apiUrlHint : widget.apiUrl,
        style: TextStyle(
          color: widget.apiUrl.isEmpty ? Colors.grey : null,
        ),
      ),
      trailing: const Icon(Icons.edit),
      onTap: () => setState(() => _isEditing = true),
    );
  }
}

class _LanguageTile extends StatelessWidget {
  final String currentCode;
  final ValueChanged<String> onChanged;

  const _LanguageTile({
    required this.currentCode,
    required this.onChanged,
  });

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context)!;

    return ListTile(
      leading: const Icon(Icons.language),
      title: Text(l10n.language),
      subtitle: Text(currentCode == 'ru' ? l10n.russian : l10n.english),
      trailing: DropdownButton<String>(
        value: currentCode,
        underline: const SizedBox(),
        items: [
          DropdownMenuItem(value: 'ru', child: Text(l10n.russian)),
          DropdownMenuItem(value: 'en', child: Text(l10n.english)),
        ],
        onChanged: (value) {
          if (value != null) onChanged(value);
        },
      ),
    );
  }
}

class _ConfigModuleCard extends StatelessWidget {
  final String title;
  final IconData icon;
  final List<Widget> children;

  const _ConfigModuleCard({
    required this.title,
    required this.icon,
    required this.children,
  });

  @override
  Widget build(BuildContext context) {
    return Card(
      margin: const EdgeInsets.symmetric(horizontal: 16, vertical: 4),
      child: ExpansionTile(
        leading: Icon(icon, color: Theme.of(context).colorScheme.primary),
        title: Text(title),
        children: [
          Padding(
            padding: const EdgeInsets.fromLTRB(16, 0, 16, 12),
            child: Column(
              children: children,
            ),
          ),
        ],
      ),
    );
  }
}

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

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

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.symmetric(vertical: 4),
      child: Row(
        mainAxisAlignment: MainAxisAlignment.spaceBetween,
        children: [
          Text(
            label,
            style: TextStyle(
              color: Colors.grey[600],
              fontSize: 13,
            ),
          ),
          Text(
            value,
            style: const TextStyle(
              fontWeight: FontWeight.w500,
              fontSize: 13,
            ),
          ),
        ],
      ),
    );
  }
}

class _SettingsTile extends StatelessWidget {
  final IconData icon;
  final String title;
  final String? subtitle;
  final VoidCallback onTap;

  const _SettingsTile({
    required this.icon,
    required this.title,
    this.subtitle,
    required this.onTap,
  });

  @override
  Widget build(BuildContext context) {
    return ListTile(
      leading: Icon(icon),
      title: Text(title),
      subtitle: subtitle != null ? Text(subtitle!) : null,
      trailing: const Icon(Icons.chevron_right),
      onTap: onTap,
    );
  }
}