// lib/screens/settings/submission_preferences_settings.dart

import 'package:flutter/material.dart';
import 'package:environment_monitoring_app/services/user_preferences_service.dart';

class _ModuleSettings {
  bool isApiEnabled;
  bool isFtpEnabled;
  List<Map<String, dynamic>> apiConfigs;
  List<Map<String, dynamic>> ftpConfigs;

  _ModuleSettings({
    this.isApiEnabled = true,
    this.isFtpEnabled = true,
    required this.apiConfigs,
    required this.ftpConfigs,
  });
}

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

  @override
  State<SubmissionPreferencesSettingsScreen> createState() =>
      _SubmissionPreferencesSettingsScreenState();
}

class _SubmissionPreferencesSettingsScreenState
    extends State<SubmissionPreferencesSettingsScreen> {
  final UserPreferencesService _preferencesService = UserPreferencesService();
  bool _isLoadingSettings = true;
  bool _isSaving = false;

  final Map<String, _ModuleSettings> _moduleSettings = {};

  final List<Map<String, String>> _configurableModules = [
    {'key': 'marine_tarball', 'name': 'Marine Tarball'},
    {'key': 'marine_in_situ', 'name': 'Marine In-Situ'},
    {'key': 'marine_investigative', 'name': 'Marine Investigative'},
    {'key': 'river_in_situ', 'name': 'River In-Situ'},
    {'key': 'river_triennial', 'name': 'River Triennial'},
    {'key': 'river_investigative', 'name': 'River Investigative'},
    {'key': 'air_installation', 'name': 'Air Installation'},
    {'key': 'air_collection', 'name': 'Air Collection'},
  ];

  @override
  void initState() {
    super.initState();
    _loadAllModuleSettings();
  }

  Future<void> _loadAllModuleSettings() async {
    setState(() => _isLoadingSettings = true);
    for (var module in _configurableModules) {
      final moduleKey = module['key']!;

      final prefs = await _preferencesService.getModulePreference(moduleKey);
      final apiConfigsWithPrefs =
      await _preferencesService.getAllApiConfigsWithModulePreferences(moduleKey);
      final ftpConfigsWithPrefs =
      await _preferencesService.getAllFtpConfigsWithModulePreferences(moduleKey);

      _moduleSettings[moduleKey] = _ModuleSettings(
        isApiEnabled: prefs?['is_api_enabled'] ?? true, // Fallback to true if null
        isFtpEnabled: prefs?['is_ftp_enabled'] ?? true, // Fallback to true if null
        apiConfigs: apiConfigsWithPrefs,
        ftpConfigs: ftpConfigsWithPrefs,
      );
    }
    if (mounted) {
      setState(() => _isLoadingSettings = false);
    }
  }

  Future<void> _saveAllModuleSettings() async {
    setState(() => _isSaving = true);

    try {
      for (var module in _configurableModules) {
        final moduleKey = module['key']!;
        final settings = _moduleSettings[moduleKey]!;

        await _preferencesService.saveModulePreference(
          moduleName: moduleKey,
          isApiEnabled: settings.isApiEnabled,
          isFtpEnabled: settings.isFtpEnabled,
        );

        await _preferencesService.saveApiLinksForModule(
            moduleKey, settings.apiConfigs);
        await _preferencesService.saveFtpLinksForModule(
            moduleKey, settings.ftpConfigs);
      }
      _showSnackBar('Submission preferences saved successfully.', isError: false);
    } catch (e) {
      _showSnackBar('Failed to save settings: $e', isError: true);
    } finally {
      if (mounted) {
        setState(() => _isSaving = 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,
        ),
      );
    }
  }

  Widget _buildSectionHeader(BuildContext context, String title) {
    return Padding(
      padding: const EdgeInsets.fromLTRB(8.0, 24.0, 8.0, 16.0),
      child: Text(
        title,
        style: Theme.of(context)
            .textTheme
            .headlineSmall
            ?.copyWith(fontWeight: FontWeight.bold),
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text("Submission Preferences"),
        actions: [
          Padding(
            padding: const EdgeInsets.only(right: 8.0),
            child: _isSaving
                ? const Center(
                child: SizedBox(
                    width: 24,
                    height: 24,
                    child: CircularProgressIndicator(color: Colors.white)))
                : IconButton(
              icon: const Icon(Icons.save),
              onPressed:
              _isLoadingSettings ? null : _saveAllModuleSettings,
              tooltip: 'Save Submission Preferences',
            ),
          )
        ],
      ),
      body: _isLoadingSettings
          ? const Center(
          child: Padding(
              padding: EdgeInsets.all(16.0),
              child: CircularProgressIndicator()))
          : ListView(
        padding: const EdgeInsets.all(16.0),
        children: [
          _buildSectionHeader(context, "Module Settings"),
          Card(
            margin: EdgeInsets.zero,
            child: ListView.builder(
              shrinkWrap: true,
              physics: const NeverScrollableScrollPhysics(),
              itemCount: _configurableModules.length,
              itemBuilder: (context, index) {
                final module = _configurableModules[index];
                final settings = _moduleSettings[module['key']];
                if (settings == null) return const SizedBox.shrink();
                return _buildModulePreferenceTile(
                    module['name']!, module['key']!, settings);
              },
            ),
          ),
        ],
      ),
    );
  }

  Widget _buildModulePreferenceTile(
      String title, String moduleKey, _ModuleSettings settings) {
    return ExpansionTile(
      title: Text(title, style: const TextStyle(fontWeight: FontWeight.bold)),
      initiallyExpanded: false, // Start collapsed
      children: [
        SwitchListTile(
          title: const Text('Enable API Submission'),
          value: settings.isApiEnabled,
          onChanged: (value) => setState(() => settings.isApiEnabled = value),
        ),
        if (settings.isApiEnabled)
          _buildDestinationList(
              'API Destinations', settings.apiConfigs, 'api_config_id'),
        const Divider(),
        SwitchListTile(
          title: const Text('Enable FTP Submission'),
          value: settings.isFtpEnabled,
          onChanged: (value) => setState(() => settings.isFtpEnabled = value),
        ),
        if (settings.isFtpEnabled)
          _buildDestinationList(
              'FTP Destinations', settings.ftpConfigs, 'ftp_config_id'),
      ],
    );
  }

  Widget _buildDestinationList(
      String title, List<Map<String, dynamic>> configs, String idKey) {
    if (configs.isEmpty) {
      return const ListTile(
        dense: true,
        title:
        Center(child: Text('No destinations configured. Sync to fetch.')),
      );
    }
    return Padding(
      padding: const EdgeInsets.fromLTRB(16.0, 8.0, 16.0, 16.0),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Padding(
            padding: const EdgeInsets.only(left: 16.0, bottom: 8.0),
            child: Text(title, style: Theme.of(context).textTheme.titleMedium),
          ),
          ...configs.map((config) {
            bool isFtp = config.containsKey('ftp_module');
            String subtitleText;

            if (isFtp) {
              subtitleText =
              'Module: ${config['ftp_module'] ?? 'N/A'} | Host: ${config['ftp_host'] ?? 'N/A'}';
            } else {
              subtitleText = config['api_url'] ?? 'No URL';
            }

            return CheckboxListTile(
              title: Text(config['config_name'] ?? 'Unnamed'),
              subtitle:
              Text(subtitleText, style: const TextStyle(fontSize: 12)),
              value: config['is_enabled'] ?? false,
              onChanged: (bool? value) {
                setState(() {
                  config['is_enabled'] = value ?? false;
                });
              },
              dense: true,
            );
          }).toList(),
        ],
      ),
    );
  }
}