import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:relationship_saver/core/config/app_config.dart';
import 'package:relationship_saver/core/config/app_theme.dart';
import 'package:relationship_saver/core/llm/llm_config.dart';
import 'package:relationship_saver/features/ai_digest/application/llm_digest_background_scheduler.dart';
import 'package:relationship_saver/features/ai_digest/application/llm_digest_orchestrator.dart';
import 'package:relationship_saver/features/ai_digest/data/llm_digest_config.dart';
import 'package:relationship_saver/features/ai_digest/presentation/ai_digest_review_view.dart';
import 'package:relationship_saver/features/auth/session_controller.dart';
import 'package:relationship_saver/features/local/local_models.dart';
import 'package:relationship_saver/features/reminders/scheduling/reminder_scheduler_provider.dart';
import 'package:relationship_saver/features/share_intake/share_capture_flow.dart';
import 'package:relationship_saver/features/share_intake/share_capture_models.dart';
import 'package:relationship_saver/features/share_intake/share_inbox_view.dart';
import 'package:relationship_saver/features/shared/frosted_card.dart';
import 'package:relationship_saver/integrations/backend/models/backend_models.dart';

class SettingsView extends ConsumerWidget {
  const SettingsView({super.key});

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final AuthSession? session = ref
        .watch(sessionControllerProvider)
        .asData
        ?.value;
    final LlmDigestConfigState digestConfig = ref.watch(
      llmDigestConfigProvider,
    );

    return LayoutBuilder(
      builder: (BuildContext context, BoxConstraints constraints) {
        final bool compact = constraints.maxWidth < 760;
        return Padding(
          padding: EdgeInsets.fromLTRB(
            compact ? 16 : 28,
            compact ? 16 : 24,
            compact ? 16 : 28,
            compact ? 20 : 28,
          ),
          child: SingleChildScrollView(
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: <Widget>[
                Text(
                  'Settings',
                  style: Theme.of(context).textTheme.headlineMedium,
                ),
                const SizedBox(height: 6),
                Text(
                  'Environment and integration configuration for this build.',
                  style: Theme.of(context).textTheme.bodyLarge?.copyWith(
                    color: AppTheme.textSecondary,
                  ),
                ),
                const SizedBox(height: 16),
                FrostedCard(
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: <Widget>[
                      _SettingRow(
                        compact: compact,
                        label: 'Signed in as',
                        value:
                            session?.user.email ??
                            session?.user.id ??
                            'Not signed in',
                      ),
                      const SizedBox(height: 12),
                      _SettingRow(
                        compact: compact,
                        label: 'Gateway mode',
                        value: AppConfig.useFakeBackend
                            ? 'Fake (offline-safe)'
                            : 'REST',
                      ),
                      const SizedBox(height: 12),
                      _SettingRow(
                        compact: compact,
                        label: 'Base URL',
                        value: AppConfig.backendBaseUrl,
                      ),
                      const SizedBox(height: 12),
                      _SettingRow(
                        compact: compact,
                        label: 'Realtime',
                        value: 'Planned later (SSE/WebSocket)',
                      ),
                      const SizedBox(height: 12),
                      _SettingRow(
                        compact: compact,
                        label: 'Local notifications',
                        value: AppConfig.enableLocalNotifications
                            ? 'Enabled'
                            : 'Disabled',
                      ),
                      const SizedBox(height: 12),
                      _SettingRow(
                        compact: compact,
                        label: 'LLM AI',
                        value: ref.watch(llmConfigProvider).isConfigured
                            ? '${_providerLabel(ref.watch(llmConfigProvider).provider)} (configured)'
                            : 'Not configured',
                      ),
                      const SizedBox(height: 12),
                      _SettingRow(
                        compact: compact,
                        label: 'AI digest',
                        value: digestConfig.enabled
                            ? 'Weekly, ${_weekdayLabel(digestConfig.preferredWeekday)} ${digestConfig.preferredHour.toString().padLeft(2, '0')}:00'
                            : 'Off',
                      ),
                      const SizedBox(height: 12),
                      _SettingRow(
                        compact: compact,
                        label: 'AI network',
                        value:
                            '${digestConfig.requireWifi ? 'Wi-Fi' : 'Any network'} + ${digestConfig.requireCharging ? 'charging' : 'battery allowed'}',
                      ),
                      const SizedBox(height: 14),
                      Wrap(
                        spacing: 8,
                        runSpacing: 8,
                        children: <Widget>[
                          OutlinedButton.icon(
                            onPressed: () => _configureLlm(context, ref),
                            icon: const Icon(Icons.smart_toy_rounded),
                            label: Text(
                              ref.watch(llmConfigProvider).isConfigured
                                  ? 'Configure AI'
                                  : 'Setup AI',
                            ),
                          ),
                          OutlinedButton.icon(
                            onPressed: () => _toggleDigest(context, ref),
                            icon: Icon(
                              digestConfig.enabled
                                  ? Icons.event_busy_rounded
                                  : Icons.event_repeat_rounded,
                            ),
                            label: Text(
                              digestConfig.enabled
                                  ? 'Disable Weekly AI Digest'
                                  : 'Enable Weekly AI Digest',
                            ),
                          ),
                          OutlinedButton.icon(
                            onPressed: ref.watch(llmConfigProvider).isConfigured
                                ? () => _runPrivateDigest(context, ref)
                                : null,
                            icon: const Icon(Icons.auto_awesome_rounded),
                            label: const Text('Run Private Digest Now'),
                          ),
                          OutlinedButton.icon(
                            onPressed: () => Navigator.of(context).push<void>(
                              MaterialPageRoute<void>(
                                builder: (BuildContext context) =>
                                    const AiDigestReviewView(),
                              ),
                            ),
                            icon: const Icon(Icons.rate_review_rounded),
                            label: const Text('Open AI Review'),
                          ),
                          OutlinedButton.icon(
                            onPressed: session == null
                                ? null
                                : () => _signOut(context, ref),
                            icon: const Icon(Icons.logout_rounded),
                            label: const Text('Sign Out'),
                          ),
                          OutlinedButton.icon(
                            onPressed: session == null
                                ? null
                                : () {
                                    ref
                                        .read(
                                          sessionControllerProvider.notifier,
                                        )
                                        .refreshProfile();
                                  },
                            icon: const Icon(Icons.refresh_rounded),
                            label: const Text('Refresh Profile'),
                          ),
                          OutlinedButton.icon(
                            onPressed: AppConfig.enableLocalNotifications
                                ? () => _requestNotificationPermissions(
                                    context,
                                    ref,
                                  )
                                : null,
                            icon: const Icon(
                              Icons.notifications_active_rounded,
                            ),
                            label: const Text('Request Notification Access'),
                          ),
                          OutlinedButton.icon(
                            onPressed: () =>
                                _simulateShareCapture(context, ref),
                            icon: const Icon(Icons.message_rounded),
                            label: const Text('Simulate Share Capture'),
                          ),
                          OutlinedButton.icon(
                            onPressed: () => Navigator.of(context).push<void>(
                              MaterialPageRoute<void>(
                                builder: (BuildContext context) =>
                                    const ShareInboxView(),
                              ),
                            ),
                            icon: const Icon(Icons.inbox_rounded),
                            label: const Text('Open Share Inbox'),
                          ),
                        ],
                      ),
                    ],
                  ),
                ),
                const SizedBox(height: 16),
                FrostedCard(
                  child: Text(
                    'Local-first privacy\n• Relationship details stay on this device in the current build.\n• Scheduled AI uses pseudonymous person tokens and a review inbox.\n• Names, aliases, sender names, URLs, and raw shared text are not sent in the digest payload.\n• iOS background digest runs are best-effort; manual runs are available here.\n\nRun options\n• Fake mode: flutter run --dart-define=USE_FAKE_BACKEND=true\n• REST mode: flutter run --dart-define=USE_FAKE_BACKEND=false --dart-define=BACKEND_BASE_URL=https://your-api',
                    style: Theme.of(context).textTheme.bodyLarge,
                  ),
                ),
              ],
            ),
          ),
        );
      },
    );
  }

  String _providerLabel(LlmProvider provider) {
    switch (provider) {
      case LlmProvider.openai:
        return 'OpenAI';
      case LlmProvider.anthropic:
        return 'Anthropic';
      case LlmProvider.google:
        return 'Google AI';
    }
  }

  String _weekdayLabel(int weekday) {
    return switch (weekday) {
      DateTime.monday => 'Mon',
      DateTime.tuesday => 'Tue',
      DateTime.wednesday => 'Wed',
      DateTime.thursday => 'Thu',
      DateTime.friday => 'Fri',
      DateTime.saturday => 'Sat',
      DateTime.sunday => 'Sun',
      _ => 'Sun',
    };
  }

  Future<void> _configureLlm(BuildContext context, WidgetRef ref) async {
    final LlmConfigState current = ref.read(llmConfigProvider);
    final _LlmConfigDraft? draft = await showDialog<_LlmConfigDraft>(
      context: context,
      builder: (BuildContext context) => _LlmConfigDialog(
        currentProvider: current.provider,
        hasApiKey: current.apiKeyConfigured,
      ),
    );
    if (draft == null || !context.mounted) {
      return;
    }

    await ref.read(llmConfigProvider.notifier).setProvider(draft.provider);
    if (draft.clearApiKey) {
      await ref.read(llmConfigProvider.notifier).clearApiKey();
    } else if (draft.apiKey.isNotEmpty) {
      await ref.read(llmConfigProvider.notifier).setApiKey(draft.apiKey);
    }

    if (context.mounted) {
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(
          content: Text(
            draft.apiKey.isNotEmpty
                ? 'AI configuration saved.'
                : draft.clearApiKey
                ? 'AI API key cleared.'
                : 'AI configuration saved.',
          ),
        ),
      );
    }
  }

  Future<void> _toggleDigest(BuildContext context, WidgetRef ref) async {
    final LlmDigestConfigState current = ref.read(llmDigestConfigProvider);
    final bool nextEnabled = !current.enabled;
    await ref.read(llmDigestConfigProvider.notifier).setEnabled(nextEnabled);
    await ref
        .read(llmDigestBackgroundSchedulerProvider)
        .configure(ref.read(llmDigestConfigProvider));
    if (!context.mounted) {
      return;
    }
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(
        content: Text(
          nextEnabled
              ? 'Weekly private AI digest enabled.'
              : 'Weekly private AI digest disabled.',
        ),
      ),
    );
  }

  Future<void> _runPrivateDigest(BuildContext context, WidgetRef ref) async {
    final ScaffoldMessengerState messenger = ScaffoldMessenger.of(context);
    messenger.showSnackBar(
      const SnackBar(content: Text('Running private AI digest...')),
    );
    final LlmDigestRunResult result = await ref
        .read(llmDigestOrchestratorProvider)
        .runManualDigest();
    if (!context.mounted) {
      return;
    }
    messenger.showSnackBar(
      SnackBar(
        content: Text(
          result.completed
              ? 'Private digest created ${result.createdDraftCount} suggestions.'
              : result.reason ?? 'Private digest did not complete.',
        ),
      ),
    );
  }

  Future<void> _signOut(BuildContext context, WidgetRef ref) async {
    await ref.read(sessionControllerProvider.notifier).signOut();
    if (context.mounted) {
      ScaffoldMessenger.of(
        context,
      ).showSnackBar(const SnackBar(content: Text('Signed out.')));
    }
  }

  Future<void> _requestNotificationPermissions(
    BuildContext context,
    WidgetRef ref,
  ) async {
    final bool granted = await ref
        .read(reminderSchedulerProvider)
        .requestPermissions();
    if (!context.mounted) {
      return;
    }
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(
        content: Text(
          granted
              ? 'Notification access granted.'
              : 'Notification access not granted.',
        ),
      ),
    );
  }

  Future<void> _simulateShareCapture(
    BuildContext context,
    WidgetRef ref,
  ) async {
    final String platformName = Theme.of(context).platform.name;
    final _ShareSimulationDraft? draft =
        await showDialog<_ShareSimulationDraft>(
          context: context,
          builder: (BuildContext context) => const _ShareSimulationDialog(),
        );
    if (draft == null) {
      return;
    }
    if (!context.mounted) {
      return;
    }

    final SharedPayload? payload = buildSharedPayloadFromRawText(
      rawText: draft.rawText,
      platform: platformName,
      sourceAppHint: draft.sourceAppHint,
    );
    if (payload == null) {
      ScaffoldMessenger.of(
        context,
      ).showSnackBar(const SnackBar(content: Text('Shared payload is empty.')));
      return;
    }

    final SharedMessageIngestResult? result = await startShareCaptureReview(
      context,
      ref: ref,
      payload: payload,
    );

    if (!context.mounted || result == null) {
      return;
    }
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(
        content: Text(shareCaptureResultMessage(result)),
        action: SnackBarAction(
          label: result.isQueuedForResolution ? 'Open Inbox' : 'Open Profile',
          onPressed: () =>
              openShareCaptureDestination(context, ref: ref, result: result),
        ),
      ),
    );
  }
}

class _SettingRow extends StatelessWidget {
  const _SettingRow({
    required this.label,
    required this.value,
    required this.compact,
  });

  final String label;
  final String value;
  final bool compact;

  @override
  Widget build(BuildContext context) {
    if (compact) {
      return Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: <Widget>[
          Text(
            label,
            style: Theme.of(
              context,
            ).textTheme.titleMedium?.copyWith(color: AppTheme.textSecondary),
          ),
          const SizedBox(height: 4),
          Text(value, style: Theme.of(context).textTheme.bodyLarge),
        ],
      );
    }

    return Row(
      crossAxisAlignment: CrossAxisAlignment.start,
      children: <Widget>[
        SizedBox(
          width: 140,
          child: Text(
            label,
            style: Theme.of(
              context,
            ).textTheme.titleMedium?.copyWith(color: AppTheme.textSecondary),
          ),
        ),
        Expanded(
          child: Text(value, style: Theme.of(context).textTheme.bodyLarge),
        ),
      ],
    );
  }
}

class _LlmConfigDraft {
  const _LlmConfigDraft({
    required this.provider,
    required this.apiKey,
    this.clearApiKey = false,
  });

  final LlmProvider provider;
  final String apiKey;
  final bool clearApiKey;
}

class _LlmConfigDialog extends StatefulWidget {
  const _LlmConfigDialog({
    required this.currentProvider,
    required this.hasApiKey,
  });

  final LlmProvider currentProvider;
  final bool hasApiKey;

  @override
  State<_LlmConfigDialog> createState() => _LlmConfigDialogState();
}

class _LlmConfigDialogState extends State<_LlmConfigDialog> {
  late LlmProvider _selectedProvider;
  late final TextEditingController _apiKeyController;

  @override
  void initState() {
    super.initState();
    _selectedProvider = widget.currentProvider;
    _apiKeyController = TextEditingController();
  }

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

  @override
  Widget build(BuildContext context) {
    return AlertDialog(
      title: const Text('Configure AI Provider'),
      content: Column(
        mainAxisSize: MainAxisSize.min,
        crossAxisAlignment: CrossAxisAlignment.start,
        children: <Widget>[
          const Text('Provider'),
          const SizedBox(height: 8),
          DropdownButtonFormField<LlmProvider>(
            initialValue: _selectedProvider,
            decoration: const InputDecoration(border: OutlineInputBorder()),
            items: const <DropdownMenuItem<LlmProvider>>[
              DropdownMenuItem<LlmProvider>(
                value: LlmProvider.openai,
                child: Text('OpenAI'),
              ),
              DropdownMenuItem<LlmProvider>(
                value: LlmProvider.anthropic,
                child: Text('Anthropic (Claude)'),
              ),
              DropdownMenuItem<LlmProvider>(
                value: LlmProvider.google,
                child: Text('Google AI'),
              ),
            ],
            onChanged: (LlmProvider? value) {
              if (value != null) {
                setState(() {
                  _selectedProvider = value;
                });
              }
            },
          ),
          const SizedBox(height: 16),
          const Text('API Key'),
          const SizedBox(height: 8),
          TextField(
            controller: _apiKeyController,
            obscureText: true,
            decoration: InputDecoration(
              hintText: widget.hasApiKey
                  ? 'Leave empty to keep current'
                  : 'Enter your API key',
              border: const OutlineInputBorder(),
            ),
          ),
        ],
      ),
      actions: <Widget>[
        TextButton(
          onPressed: () => Navigator.of(context).pop(),
          child: const Text('Cancel'),
        ),
        if (widget.hasApiKey)
          TextButton(
            onPressed: () {
              Navigator.of(context).pop(
                _LlmConfigDraft(
                  provider: _selectedProvider,
                  apiKey: '',
                  clearApiKey: true,
                ),
              );
            },
            child: const Text('Clear Key'),
          ),
        FilledButton(
          onPressed: () {
            Navigator.of(context).pop(
              _LlmConfigDraft(
                provider: _selectedProvider,
                apiKey: _apiKeyController.text.trim(),
              ),
            );
          },
          child: const Text('Save'),
        ),
      ],
    );
  }
}

class _ShareSimulationDraft {
  const _ShareSimulationDraft({
    required this.rawText,
    required this.sourceAppHint,
  });

  final String rawText;
  final String sourceAppHint;
}

class _ShareSimulationDialog extends StatefulWidget {
  const _ShareSimulationDialog();

  @override
  State<_ShareSimulationDialog> createState() => _ShareSimulationDialogState();
}

class _ShareSimulationDialogState extends State<_ShareSimulationDialog> {
  late final TextEditingController _controller;
  String _selectedSourceApp = 'whatsapp';

  @override
  void initState() {
    super.initState();
    _controller = TextEditingController(
      text: '[2/18/26, 20:11] Ava Hart: Can we do coffee this Saturday?',
    );
  }

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

  @override
  Widget build(BuildContext context) {
    return AlertDialog(
      title: const Text('Simulate Share Capture'),
      content: Column(
        mainAxisSize: MainAxisSize.min,
        children: <Widget>[
          DropdownButtonFormField<String>(
            initialValue: _selectedSourceApp,
            decoration: const InputDecoration(labelText: 'Source app'),
            items: const <DropdownMenuItem<String>>[
              DropdownMenuItem<String>(
                value: 'whatsapp',
                child: Text('WhatsApp'),
              ),
              DropdownMenuItem<String>(value: 'signal', child: Text('Signal')),
              DropdownMenuItem<String>(value: 'notes', child: Text('Notes')),
              DropdownMenuItem<String>(
                value: 'share_sheet',
                child: Text('Generic text/link'),
              ),
            ],
            onChanged: (String? value) {
              if (value == null) {
                return;
              }
              setState(() {
                _selectedSourceApp = value;
              });
            },
          ),
          const SizedBox(height: 12),
          TextField(
            controller: _controller,
            minLines: 3,
            maxLines: 6,
            decoration: const InputDecoration(
              hintText: 'Paste shared text or URL payload',
            ),
          ),
        ],
      ),
      actions: <Widget>[
        TextButton(
          onPressed: () => Navigator.of(context).pop(),
          child: const Text('Cancel'),
        ),
        FilledButton(
          onPressed: () {
            final String rawText = _controller.text.trim();
            if (rawText.isEmpty) {
              return;
            }
            Navigator.of(context).pop(
              _ShareSimulationDraft(
                rawText: rawText,
                sourceAppHint: _selectedSourceApp,
              ),
            );
          },
          child: const Text('Import'),
        ),
      ],
    );
  }
}