import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import 'package:intl/intl.dart';
import 'package:environment_monitoring_app/auth_provider.dart';
import 'package:environment_monitoring_app/services/settings_service.dart';

class SettingsScreen extends StatefulWidget {
  const SettingsScreen({super.key});

  @override
  State<SettingsScreen> createState() => _SettingsScreenState();
}

class _SettingsScreenState extends State<SettingsScreen> {
  final SettingsService _settingsService = SettingsService();
  bool _isSyncingData = false;

  final TextEditingController _tarballSearchController = TextEditingController();
  String _tarballSearchQuery = '';
  final TextEditingController _manualSearchController = TextEditingController();
  String _manualSearchQuery = '';
  final TextEditingController _riverManualSearchController = TextEditingController();
  String _riverManualSearchQuery = '';
  final TextEditingController _riverTriennialSearchController = TextEditingController();
  String _riverTriennialSearchQuery = '';
  final TextEditingController _airStationSearchController = TextEditingController();
  String _airStationSearchQuery = '';
  final TextEditingController _airClientSearchController = TextEditingController();
  String _airClientSearchQuery = '';

  @override
  void initState() {
    super.initState();
    _tarballSearchController.addListener(_onTarballSearchChanged);
    _manualSearchController.addListener(_onManualSearchChanged);
    _riverManualSearchController.addListener(_onRiverManualSearchChanged);
    _riverTriennialSearchController.addListener(_onRiverTriennialSearchChanged);
    _airStationSearchController.addListener(_onAirStationSearchChanged);
    _airClientSearchController.addListener(_onAirClientSearchChanged);
  }

  @override
  void dispose() {
    _tarballSearchController.dispose();
    _manualSearchController.dispose();
    _riverManualSearchController.dispose();
    _riverTriennialSearchController.dispose();
    _airStationSearchController.dispose();
    _airClientSearchController.dispose();
    super.dispose();
  }

  void _onTarballSearchChanged() {
    setState(() {
      _tarballSearchQuery = _tarballSearchController.text;
    });
  }

  void _onManualSearchChanged() {
    setState(() {
      _manualSearchQuery = _manualSearchController.text;
    });
  }

  void _onRiverManualSearchChanged() {
    setState(() {
      _riverManualSearchQuery = _riverManualSearchController.text;
    });
  }

  void _onRiverTriennialSearchChanged() {
    setState(() {
      _riverTriennialSearchQuery = _riverTriennialSearchController.text;
    });
  }

  void _onAirStationSearchChanged() {
    setState(() {
      _airStationSearchQuery = _airStationSearchController.text;
    });
  }

  void _onAirClientSearchChanged() {
    setState(() {
      _airClientSearchQuery = _airClientSearchController.text;
    });
  }

  Future<void> _manualDataSync() async {
    if (_isSyncingData) return;
    setState(() => _isSyncingData = true);

    final auth = Provider.of<AuthProvider>(context, listen: false);

    try {
      await auth.syncAllData(forceRefresh: true);

      if (mounted) {
        _showSnackBar('Data synced successfully.', isError: false);
      }
    } catch (e) {
      if (mounted) {
        _showSnackBar('Data sync failed. Please check your connection.', isError: true);
      }
    } finally {
      if (mounted) {
        setState(() => _isSyncingData = false);
      }
    }
  }

  void _showSnackBar(String message, {bool isError = false}) {
    if (mounted) {
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(
          content: Text(message),
          backgroundColor: isError ? Theme.of(context).colorScheme.error : Colors.green,
        ),
      );
    }
  }

  @override
  Widget build(BuildContext context) {
    final auth = Provider.of<AuthProvider>(context);
    final lastSync = auth.lastSyncTimestamp;

    // Get the synced data from the provider.
    final appSettings = auth.appSettings;
    final parameterLimits = auth.parameterLimits;
    final apiConfigs = auth.apiConfigs;
    final ftpConfigs = auth.ftpConfigs;
    final airClients = auth.airClients;
    final departments = auth.departments;

    // Find Department IDs
    final int? airDepartmentId = departments?.firstWhere((d) => d['department_name'] == 'Air', orElse: () => {})?['department_id'];
    final int? riverDepartmentId = departments?.firstWhere((d) => d['department_name'] == 'River', orElse: () => {})?['department_id'];
    final int? marineDepartmentId = departments?.firstWhere((d) => d['department_name'] == 'Marine', orElse: () => {})?['department_id'];

    // Filter Parameter Limits by Department ID
    final filteredAirLimits = parameterLimits?.where((limit) => limit['department_id'] == airDepartmentId).toList();
    final filteredRiverLimits = parameterLimits?.where((limit) => limit['department_id'] == riverDepartmentId).toList();
    final filteredMarineLimits = parameterLimits?.where((limit) => limit['department_id'] == marineDepartmentId).toList();

    // Filter Marine Stations
    final filteredTarballStations = (auth.tarballStations?.where((station) {
      final stationName = station['tbl_station_name']?.toLowerCase() ?? '';
      final stationCode = station['tbl_station_code']?.toLowerCase() ?? '';
      final query = _tarballSearchQuery.toLowerCase();
      return stationName.contains(query) || stationCode.contains(query);
    }).toList())?.cast<Map<String, dynamic>>();

    final filteredManualStations = (auth.manualStations?.where((station) {
      final stationName = station['man_station_name']?.toLowerCase() ?? '';
      final stationCode = station['man_station_code']?.toLowerCase() ?? '';
      final query = _manualSearchQuery.toLowerCase();
      return stationName.contains(query) || stationCode.contains(query);
    }).toList())?.cast<Map<String, dynamic>>();

    // Filter River Stations
    final filteredRiverManualStations = (auth.riverManualStations?.where((station) {
      final riverName = station['sampling_river']?.toLowerCase() ?? '';
      final stationCode = station['sampling_station_code']?.toLowerCase() ?? '';
      final basinName = station['sampling_basin']?.toLowerCase() ?? '';
      final query = _riverManualSearchQuery.toLowerCase();
      return riverName.contains(query) || stationCode.contains(query) || basinName.contains(query);
    }).toList())?.cast<Map<String, dynamic>>();

    final filteredRiverTriennialStations = (auth.riverTriennialStations?.where((station) {
      final riverName = station['triennial_river']?.toLowerCase() ?? '';
      final stationCode = station['triennial_station_code']?.toLowerCase() ?? '';
      final basinName = station['triennial_basin']?.toLowerCase() ?? '';
      final query = _riverTriennialSearchQuery.toLowerCase();
      return riverName.contains(query) || stationCode.contains(query) || basinName.contains(query);
    }).toList())?.cast<Map<String, dynamic>>();

    // Filter Air Stations
    final filteredAirStations = (auth.airManualStations?.where((station) {
      final stationName = station['station_name']?.toLowerCase() ?? '';
      final stationCode = station['station_code']?.toLowerCase() ?? '';
      final query = _airStationSearchQuery.toLowerCase();
      return stationName.contains(query) || stationCode.contains(query);
    }).toList())?.cast<Map<String, dynamic>>();

    // Filter Air Clients
    final filteredAirClients = (auth.airClients?.where((client) {
      final clientName = client['client_name']?.toLowerCase() ?? '';
      final clientId = client['client_id']?.toString().toLowerCase() ?? '';
      final query = _airClientSearchQuery.toLowerCase();
      return clientName.contains(query) || clientId.contains(query);
    }).toList())?.cast<Map<String, dynamic>>();

    return Scaffold(
      appBar: AppBar(
        title: const Text("Settings"),
      ),
      body: SingleChildScrollView(
        padding: const EdgeInsets.all(24.0),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            _buildSectionHeader(context, "Synchronization"),
            Card(
              margin: EdgeInsets.zero,
              child: Padding(
                padding: const EdgeInsets.all(16.0),
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.stretch,
                  children: [
                    Text("Last Data Sync:", style: Theme.of(context).textTheme.titleMedium),
                    const SizedBox(height: 4),
                    Text(lastSync != null ? DateFormat('yyyy-MM-dd HH:mm:ss').format(lastSync.toLocal()) : 'Never', style: Theme.of(context).textTheme.bodyLarge),
                    const SizedBox(height: 16),
                    ElevatedButton.icon(
                      onPressed: _isSyncingData ? null : _manualDataSync,
                      icon: _isSyncingData ? const SizedBox(width: 20, height: 20, child: CircularProgressIndicator(strokeWidth: 2, color: Colors.white)) : const Icon(Icons.cloud_sync),
                      label: Text(_isSyncingData ? 'Syncing Data...' : 'Sync App Data'),
                      style: ElevatedButton.styleFrom(minimumSize: const Size(double.infinity, 50)),
                    ),
                  ],
                ),
              ),
            ),
            const SizedBox(height: 32),

            Text("Telegram Alert Settings", style: Theme.of(context).textTheme.headlineSmall?.copyWith(fontWeight: FontWeight.bold)),
            const SizedBox(height: 16),
            Card(
              margin: EdgeInsets.zero,
              child: Padding(
                padding: const EdgeInsets.all(16.0),
                child: Column(
                  children: [
                    ExpansionTile(
                      title: const Text('Marine Alerts', style: TextStyle(fontWeight: FontWeight.bold)),
                      initiallyExpanded: false,
                      children: [
                        _buildChatIdEntry('In-Situ', _settingsService.getInSituChatId(appSettings)),
                        _buildChatIdEntry('Tarball', _settingsService.getTarballChatId(appSettings)),
                        _buildChatIdEntry('Investigative', _settingsService.getMarineInvestigativeChatId(appSettings)),
                      ],
                    ),
                    ExpansionTile(
                      title: const Text('River Alerts', style: TextStyle(fontWeight: FontWeight.bold)),
                      initiallyExpanded: false,
                      children: [
                        _buildChatIdEntry('In-Situ', _settingsService.getRiverInSituChatId(appSettings)),
                        _buildChatIdEntry('Triennial', _settingsService.getRiverTriennialChatId(appSettings)),
                        _buildChatIdEntry('Investigative', _settingsService.getRiverInvestigativeChatId(appSettings)),
                      ],
                    ),
                    ExpansionTile(
                      title: const Text('Air Alerts', style: TextStyle(fontWeight: FontWeight.bold)),
                      initiallyExpanded: false,
                      children: [
                        _buildChatIdEntry('Manual', _settingsService.getAirManualChatId(appSettings)),
                        _buildChatIdEntry('Investigative', _settingsService.getAirInvestigativeChatId(appSettings)),
                      ],
                    ),
                  ],
                ),
              ),
            ),
            const SizedBox(height: 32),

            _buildSectionHeader(context, "Configurations"),
            Card(
              margin: EdgeInsets.zero,
              child: Column(
                children: [
                  _buildExpansionTile(
                    title: 'Air Parameter Limits',
                    leadingIcon: Icons.poll,
                    child: _buildInfoList(filteredAirLimits, (item) => _buildParameterLimitEntry(item)),
                  ),
                  _buildExpansionTile(
                    title: 'River Parameter Limits',
                    leadingIcon: Icons.poll,
                    child: _buildInfoList(filteredRiverLimits, (item) => _buildParameterLimitEntry(item)),
                  ),
                  _buildExpansionTile(
                    title: 'Marine Parameter Limits',
                    leadingIcon: Icons.poll,
                    child: _buildInfoList(filteredMarineLimits, (item) => _buildParameterLimitEntry(item)),
                  ),
                  _buildExpansionTile(
                    title: 'API Configurations',
                    leadingIcon: Icons.cloud,
                    child: _buildInfoList(apiConfigs, (item) => _buildKeyValueEntry(item, 'config_name', 'api_url')),
                  ),
                  _buildExpansionTile(
                    title: 'FTP Configurations',
                    leadingIcon: Icons.folder,
                    child: _buildInfoList(ftpConfigs, (item) => _buildFtpConfigEntry(item)),
                  ),
                ],
              ),
            ),
            const SizedBox(height: 32),

            _buildSectionHeader(context, "Air Clients"),
            Card(
              margin: EdgeInsets.zero,
              child: Column(
                children: [
                  _buildExpansionTile(
                    title: 'Air Clients',
                    leadingIcon: Icons.air,
                    child: Column(
                      children: [
                        _buildSearchBar(
                          controller: _airClientSearchController,
                          labelText: 'Search Air Clients',
                          hintText: 'Search by name or ID',
                        ),
                        const SizedBox(height: 16),
                        _buildClientList(
                          filteredAirClients,
                          'No matching air clients found.',
                          'No air clients available. Sync to download.',
                              (client) => _buildClientTile(
                            title: client['client_name'] ?? 'N/A',
                            subtitle: 'ID: ${client['client_id'] ?? 'N/A'}',
                          ),
                          height: 250,
                        ),
                      ],
                    ),
                  ),
                ],
              ),
            ),
            const SizedBox(height: 32),

            _buildSectionHeader(context, "Stations Info"),
            Card(
              margin: EdgeInsets.zero,
              child: Column(
                children: [
                  _buildExpansionTile(
                    title: 'Marine Stations',
                    leadingIcon: Icons.waves,
                    child: Column(
                      children: [
                        _buildSearchBar(
                          controller: _tarballSearchController,
                          labelText: 'Search Tarball Stations',
                          hintText: 'Search by name or code',
                        ),
                        const SizedBox(height: 16),
                        _buildStationList(
                          filteredTarballStations,
                          'No matching tarball stations found.',
                          'No tarball stations available. Sync to download.',
                              (station) => _buildStationTile(
                              title: station['tbl_station_name'] ?? 'N/A',
                              subtitle: 'Code: ${station['tbl_station_code'] ?? 'N/A'}',
                              type: 'Tarball'
                          ),
                          height: 250,
                        ),
                        const SizedBox(height: 16),
                        _buildSearchBar(
                          controller: _manualSearchController,
                          labelText: 'Search Manual Stations',
                          hintText: 'Search by name or code',
                        ),
                        const SizedBox(height: 16),
                        _buildStationList(
                          filteredManualStations,
                          'No matching manual stations found.',
                          'No manual stations available. Sync to download.',
                              (station) => _buildStationTile(
                              title: station['man_station_name'] ?? 'N/A',
                              subtitle: 'Code: ${station['man_station_code'] ?? 'N/A'}',
                              type: 'Manual'
                          ),
                          height: 250,
                        ),
                      ],
                    ),
                  ),
                  _buildExpansionTile(
                    title: 'River Stations',
                    leadingIcon: Icons.water,
                    child: Column(
                      children: [
                        _buildSearchBar(
                          controller: _riverManualSearchController,
                          labelText: 'Search River Manual Stations',
                          hintText: 'Search by name, code, or basin',
                        ),
                        const SizedBox(height: 16),
                        _buildStationList(
                          filteredRiverManualStations,
                          'No matching river manual stations found.',
                          'No river manual stations available. Sync to download.',
                              (station) => _buildStationTile(
                              title: station['sampling_river'] ?? 'N/A',
                              subtitle: 'Code: ${station['sampling_station_code'] ?? 'N/A'}, Basin: ${station['sampling_basin'] ?? 'N/A'}',
                              type: 'River Manual'
                          ),
                          height: 250,
                        ),
                        const SizedBox(height: 16),
                        _buildSearchBar(
                          controller: _riverTriennialSearchController,
                          labelText: 'Search River Triennial Stations',
                          hintText: 'Search by name, code, or basin',
                        ),
                        const SizedBox(height: 16),
                        _buildStationList(
                          filteredRiverTriennialStations,
                          'No matching river triennial stations found.',
                          'No river triennial stations available. Sync to download.',
                              (station) => _buildStationTile(
                              title: station['triennial_river'] ?? 'N/A',
                              subtitle: 'Code: ${station['triennial_station_code'] ?? 'N/A'}, Basin: ${station['triennial_basin'] ?? 'N/A'}',
                              type: 'River Triennial'
                          ),
                          height: 250,
                        ),
                      ],
                    ),
                  ),
                  _buildExpansionTile(
                    title: 'Air Stations',
                    leadingIcon: Icons.air,
                    child: Column(
                      children: [
                        _buildSearchBar(
                          controller: _airStationSearchController,
                          labelText: 'Search Air Stations',
                          hintText: 'Search by name or code',
                        ),
                        const SizedBox(height: 16),
                        _buildStationList(
                          filteredAirStations,
                          'No matching air stations found.',
                          'No air stations available. Sync to download.',
                              (station) => _buildStationTile(
                              title: station['station_name'] ?? 'N/A',
                              subtitle: 'Code: ${station['station_code'] ?? 'N/A'}',
                              type: 'Air'
                          ),
                          height: 250,
                        ),
                      ],
                    ),
                  ),
                ],
              ),
            ),
            const SizedBox(height: 32),

            _buildSectionHeader(context, "Other Information"),
            Card(
              margin: EdgeInsets.zero,
              child: Column(
                children: [
                  ListTile(
                    leading: const Icon(Icons.info_outline),
                    title: const Text('App Version'),
                    subtitle: const Text('1.2.03'),
                    dense: true,
                  ),
                  ListTile(
                    leading: const Icon(Icons.privacy_tip_outlined),
                    title: const Text('Privacy Policy'),
                    onTap: () {},
                    dense: true,
                  ),
                ],
              ),
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildSectionHeader(BuildContext context, String title) {
    return Padding(
      padding: const EdgeInsets.only(bottom: 16.0),
      child: Text(
        title,
        style: Theme.of(context).textTheme.headlineSmall?.copyWith(fontWeight: FontWeight.bold),
      ),
    );
  }

  Widget _buildExpansionTile({
    required String title,
    required IconData leadingIcon,
    required Widget child,
  }) {
    return ExpansionTile(
      leading: Icon(leadingIcon),
      title: Text(title, style: const TextStyle(fontWeight: FontWeight.bold)),
      children: [
        child,
      ],
    );
  }

  Widget _buildInfoList(List<Map<String, dynamic>>? items, Widget Function(Map<String, dynamic>) itemBuilder) {
    if (items == null || items.isEmpty) {
      return const ListTile(
        title: Text('No data available. Sync to download.'),
        dense: true,
      );
    }
    return Column(
      children: items.map((item) => itemBuilder(item)).toList(),
    );
  }

  Widget _buildChatIdEntry(String label, String value) {
    return ListTile(
      contentPadding: EdgeInsets.zero,
      leading: const Icon(Icons.telegram, size: 20),
      title: Text('$label Chat ID'),
      subtitle: Text(value.isNotEmpty ? value : 'Not Set'),
      dense: true,
    );
  }

  Widget _buildKeyValueEntry(Map<String, dynamic> item, String key1, String key2) {
    return ListTile(
      contentPadding: const EdgeInsets.symmetric(horizontal: 24.0, vertical: 4.0),
      title: Text(item[key1]?.toString() ?? 'N/A', style: const TextStyle(fontSize: 14)),
      subtitle: Text(item[key2]?.toString() ?? 'N/A', style: const TextStyle(fontSize: 12)),
      dense: true,
    );
  }

  Widget _buildParameterLimitEntry(Map<String, dynamic> item) {
    final paramName = item['param_parameter_list']?.toString() ?? 'N/A';
    final upperLimit = item['param_upper_limit']?.toString() ?? 'N/A';
    final lowerLimit = item['param_lower_limit']?.toString() ?? 'N/A';
    String unit = '';

    // Hardcoded units as they are not available in the provided data
    if (paramName.toLowerCase() == 'ph') {
      unit = 'pH units';
    } else if (paramName.toLowerCase() == 'temp') {
      unit = '°C';
    }

    return Padding(
      padding: const EdgeInsets.symmetric(horizontal: 24.0, vertical: 8.0),
      child: Row(
        mainAxisAlignment: MainAxisAlignment.spaceBetween,
        children: [
          Expanded(
            flex: 2,
            child: Text(
              lowerLimit,
              style: const TextStyle(fontSize: 14, fontWeight: FontWeight.bold),
              textAlign: TextAlign.start,
            ),
          ),
          Expanded(
            flex: 5,
            child: Column(
              children: [
                Row(
                  mainAxisAlignment: MainAxisAlignment.center,
                  children: [
                    const Icon(Icons.science_outlined, size: 16),
                    const SizedBox(width: 8),
                    Text(
                      paramName,
                      style: const TextStyle(fontSize: 14),
                    ),
                  ],
                ),
                Text(
                  unit,
                  style: const TextStyle(fontSize: 12, fontStyle: FontStyle.italic, color: Colors.grey),
                ),
              ],
            ),
          ),
          Expanded(
            flex: 2,
            child: Text(
              upperLimit,
              style: const TextStyle(fontSize: 14, fontWeight: FontWeight.bold),
              textAlign: TextAlign.end,
            ),
          ),
        ],
      ),
    );
  }

  Widget _buildFtpConfigEntry(Map<String, dynamic> item) {
    return ListTile(
      contentPadding: const EdgeInsets.symmetric(horizontal: 24.0, vertical: 4.0),
      title: Text(item['config_name']?.toString() ?? 'N/A', style: const TextStyle(fontSize: 14)),
      subtitle: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text('Host: ${item['ftp_host']?.toString() ?? 'N/A'}', style: const TextStyle(fontSize: 12)),
          Text('User: ${item['ftp_user']?.toString() ?? 'N/A'}', style: const TextStyle(fontSize: 12)),
          Text('Pass: ${item['ftp_pass']?.toString() ?? 'N/A'}', style: const TextStyle(fontSize: 12)),
          Text('Port: ${item['ftp_port']?.toString() ?? 'N/A'}', style: const TextStyle(fontSize: 12)),
        ],
      ),
      leading: const Icon(Icons.folder_shared_outlined),
      dense: true,
    );
  }

  Widget _buildSearchBar({
    required TextEditingController controller,
    required String labelText,
    required String hintText,
  }) {
    return TextField(
      controller: controller,
      decoration: InputDecoration(
        labelText: labelText,
        hintText: hintText,
        prefixIcon: const Icon(Icons.search),
        border: OutlineInputBorder(borderRadius: BorderRadius.circular(8.0)),
        suffixIcon: controller.text.isNotEmpty
            ? IconButton(icon: const Icon(Icons.clear), onPressed: () => controller.clear())
            : null,
      ),
      style: const TextStyle(fontSize: 14),
    );
  }

  Widget _buildStationList(
      List<Map<String, dynamic>>? stations,
      String noMatchText,
      String noDataText,
      Widget Function(Map<String, dynamic>) itemBuilder,
      {double height = 250}) {
    if (stations == null || stations.isEmpty) {
      return Center(
        child: Padding(
          padding: const EdgeInsets.all(16.0),
          child: Text(
            _isSyncingData ? 'Loading...' : (stations == null ? noDataText : noMatchText),
            textAlign: TextAlign.center,
          ),
        ),
      );
    }

    return SizedBox(
      height: height,
      child: ListView.builder(
        itemCount: stations.length,
        itemBuilder: (context, index) {
          final station = stations[index];
          return itemBuilder(station);
        },
      ),
    );
  }

  Widget _buildStationTile({required String title, required String subtitle, required String type}) {
    return ListTile(
      title: Text(title, style: const TextStyle(fontSize: 14)),
      subtitle: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(subtitle, style: const TextStyle(fontSize: 12)),
          Text('Type: $type', style: const TextStyle(fontSize: 12, fontStyle: FontStyle.italic)),
        ],
      ),
      dense: true,
    );
  }

  Widget _buildClientList(
      List<Map<String, dynamic>>? clients,
      String noMatchText,
      String noDataText,
      Widget Function(Map<String, dynamic>) itemBuilder,
      {double height = 250}) {
    if (clients == null || clients.isEmpty) {
      return Center(
        child: Padding(
          padding: const EdgeInsets.all(16.0),
          child: Text(
            _isSyncingData ? 'Loading...' : (clients == null ? noDataText : noMatchText),
            textAlign: TextAlign.center,
          ),
        ),
      );
    }

    return SizedBox(
      height: height,
      child: ListView.builder(
        itemCount: clients.length,
        itemBuilder: (context, index) {
          final client = clients[index];
          return itemBuilder(client);
        },
      ),
    );
  }

  Widget _buildClientTile({required String title, required String subtitle}) {
    return ListTile(
      title: Text(title, style: const TextStyle(fontSize: 14)),
      subtitle: Text(subtitle, style: const TextStyle(fontSize: 12)),
      dense: true,
    );
  }
}