import 'dart:async';
import 'dart:convert';
import 'dart:io';
import 'dart:math';

import 'package:crypto/crypto.dart' as mcrypto;
import 'package:pyramid/core/fcm_push_service.dart';
import 'package:pyramid/core/notification_service.dart' show openBatteryOptimizationSettings;
import 'package:file_picker/file_picker.dart';
import 'package:flutter/foundation.dart' show compute;
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:flutter_webrtc/flutter_webrtc.dart';
import 'package:http/http.dart' as http;
import 'package:matrix/encryption/ssss.dart';
import 'package:matrix/encryption/utils/bootstrap.dart';
import 'package:matrix/encryption/utils/key_verification.dart' show KeyVerification, KeyVerificationEmoji, KeyVerificationState;
import 'package:matrix/matrix.dart';
import 'package:pretty_qr_code/pretty_qr_code.dart';
import 'package:path_provider/path_provider.dart';
import 'package:pointycastle/export.dart' as pc;
import 'package:pyramid/core/app_state.dart';
import 'package:pyramid/core/auth_log.dart';
import 'package:pyramid/core/e2ee_diagnostics.dart';
import 'package:pyramid/features/auth/bootstrap_dialog.dart' show isKeyBackupMissing;
import 'package:pyramid/features/call_signaling/call_signaling_service.dart';
import 'package:pyramid/features/voice_channel/voice_channel_service.dart';
import 'package:pyramid/core/matrix_client.dart';
import 'package:pyramid/core/settings_prefs.dart';
import 'package:pyramid/core/theme.dart';
import 'package:pyramid/core/update_checker.dart';
import 'package:pyramid/widgets/update_download_dialog.dart';
import 'package:url_launcher/url_launcher.dart';
import 'package:pyramid/widgets/banner_crop_dialog.dart';
import 'package:pyramid/widgets/hover_region.dart';
import 'package:pyramid/widgets/mxc_image.dart';
import 'package:pyramid/widgets/pyramid_loader.dart';

part 'settings/settings_shared.dart';
part 'settings/settings_profile.dart';
part 'settings/settings_notifications.dart';
part 'settings/settings_appearance.dart';
part 'settings/settings_voice.dart';
part 'settings/settings_keybinds.dart';
part 'settings/settings_privacy.dart';
part 'settings/settings_sessions.dart';
part 'settings/settings_verification.dart';
part 'settings/encryption/megolm_crypto.dart';
part 'settings/encryption/encryption_section.dart';
part 'settings/encryption/recovery_key_dialogs.dart';
part 'settings/encryption/fingerprint_passphrase.dart';
part 'settings/settings_account.dart';
part 'settings/settings_about.dart';

class SettingsModal extends ConsumerStatefulWidget {
  final VoidCallback onClose;
  const SettingsModal({super.key, required this.onClose});

  @override
  ConsumerState<SettingsModal> createState() => _SettingsModalState();
}

class _SettingsModalState extends ConsumerState<SettingsModal> {
  // null = show the category list (mobile). On desktop it falls back to the
  // first section so content is always visible.
  String? _section;

  // Categories shared by the desktop sidebar and the mobile list/detail.
  static const List<(String, String, IconData)> _categories = [
    ('profile', 'Mein Profil', Icons.person_outline_rounded),
    ('notifications', 'Benachrichtigungen', Icons.notifications_none_rounded),
    ('appearance', 'Erscheinungsbild', Icons.palette_outlined),
    ('voice', 'Sprache & Video', Icons.headphones_rounded),
    ('keys', 'Tastaturkürzel', Icons.keyboard_rounded),
    ('privacy', 'Datenschutz', Icons.lock_outline_rounded),
    ('sessions', 'Sitzungen', Icons.devices_rounded),
    ('encryption', 'Verschlüsselung', Icons.shield_outlined),
    ('about', 'Über Pyramid', Icons.info_outline_rounded),
  ];

  String _titleFor(String id) =>
      _categories.firstWhere((c) => c.$1 == id, orElse: () => (id, id, Icons.settings)).$2;

  @override
  Widget build(BuildContext context) {
    final pt = PyramidTheme.of(context);
    final isDark = ref.watch(themeModeProvider);
    final accentIdx = ref.watch(accentProvider);
    final radius = ref.watch(radiusProvider);
    final density = ref.watch(densityProvider);
    final motion = ref.watch(motionProvider);

    final size = MediaQuery.sizeOf(context);
    final isMobile = size.width < 700;

    return GestureDetector(
      onTap: widget.onClose,
      child: Container(
        color: Colors.black.withAlpha(150),
        child: Center(
          child: GestureDetector(
            onTap: () {},
            child: Container(
              constraints: const BoxConstraints(maxWidth: 820, maxHeight: 660),
              width: isMobile ? size.width * 0.97 : 740,
              height: isMobile ? size.height * 0.92 : 560,
              decoration: BoxDecoration(
                color: pt.bg1,
                borderRadius: BorderRadius.circular(pt.rXl),
                border: Border.all(color: pt.border),
                boxShadow: [
                  BoxShadow(
                    color: Colors.black.withAlpha(130),
                    blurRadius: 40,
                    offset: const Offset(0, 12),
                  ),
                ],
              ),
              child: ClipRRect(
                borderRadius: BorderRadius.circular(pt.rXl),
                child: isMobile
                    ? _mobileLayout(pt, isDark, accentIdx, radius, density, motion)
                    : _desktopLayout(pt, isDark, accentIdx, radius, density, motion),
              ),
            ),
          ),
        ),
      ),
    );
  }

  // ── Desktop: sidebar + content side by side ──────────────────────────────
  Widget _desktopLayout(PyramidTheme pt, bool isDark, int accentIdx,
      double radius, double density, double motion) {
    final active = _section ?? 'appearance';
    return Row(
      children: [
        Container(
          width: 200,
          decoration: BoxDecoration(
            color: pt.bg2,
            border: Border(right: BorderSide(color: pt.border)),
          ),
          child: SingleChildScrollView(
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                const SizedBox(height: 16),
                _NavSection('Account', pt),
                _NavItem('profile', 'Mein Profil', Icons.person_outline_rounded, active, pt, () => setState(() => _section = 'profile')),
                _NavItem('notifications', 'Benachrichtigungen', Icons.notifications_none_rounded, active, pt, () => setState(() => _section = 'notifications')),
                const SizedBox(height: 14),
                _NavSection('App', pt),
                _NavItem('appearance', 'Erscheinungsbild', Icons.palette_outlined, active, pt, () => setState(() => _section = 'appearance')),
                _NavItem('voice', 'Sprache & Video', Icons.headphones_rounded, active, pt, () => setState(() => _section = 'voice')),
                _NavItem('keys', 'Tastaturkürzel', Icons.keyboard_rounded, active, pt, () => setState(() => _section = 'keys')),
                const SizedBox(height: 14),
                _NavSection('Sicherheit', pt),
                _NavItem('privacy', 'Datenschutz', Icons.lock_outline_rounded, active, pt, () => setState(() => _section = 'privacy')),
                _NavItem('sessions', 'Sitzungen', Icons.devices_rounded, active, pt, () => setState(() => _section = 'sessions')),
                _NavItem('encryption', 'Verschlüsselung', Icons.shield_outlined, active, pt, () => setState(() => _section = 'encryption')),
                const SizedBox(height: 14),
                _NavItem('about', 'Über Pyramid', Icons.info_outline_rounded, active, pt, () => setState(() => _section = 'about')),
                const Divider(height: 24, indent: 12, endIndent: 12),
                _LogoutNavButton(pt: pt, isMobile: false, onClose: widget.onClose),
                const SizedBox(height: 16),
              ],
            ),
          ),
        ),
        Expanded(
          child: Stack(
            children: [
              Padding(
                padding: const EdgeInsets.all(28),
                child: _buildContent(pt, isDark, accentIdx, radius, density, motion, active),
              ),
              Positioned(
                top: 8,
                right: 8,
                child: PyrIconBtn(
                  icon: const Icon(Icons.close_rounded, size: 20),
                  tooltip: 'Schließen',
                  onPressed: widget.onClose,
                ),
              ),
            ],
          ),
        ),
      ],
    );
  }

  // ── Mobile: full-width category list → detail with a back arrow ───────────
  Widget _mobileLayout(PyramidTheme pt, bool isDark, int accentIdx,
      double radius, double density, double motion) {
    final section = _section;
    if (section == null) {
      // Category list
      return Column(
        children: [
          _MobileHeader(title: 'Einstellungen', pt: pt, onClose: widget.onClose),
          Expanded(
            child: ListView(
              padding: const EdgeInsets.symmetric(vertical: 8),
              children: [
                for (final c in _categories)
                  _MobileCategoryTile(
                    label: c.$2,
                    icon: c.$3,
                    pt: pt,
                    onTap: () => setState(() => _section = c.$1),
                  ),
                const Divider(height: 24, indent: 16, endIndent: 16),
                _LogoutNavButton(pt: pt, isMobile: false, onClose: widget.onClose),
                const SizedBox(height: 16),
              ],
            ),
          ),
        ],
      );
    }
    // Detail view with a back arrow
    return Column(
      children: [
        _MobileHeader(
          title: _titleFor(section),
          pt: pt,
          onBack: () => setState(() => _section = null),
          onClose: widget.onClose,
        ),
        Expanded(
          child: Padding(
            padding: const EdgeInsets.fromLTRB(16, 8, 16, 16),
            child: _buildContent(pt, isDark, accentIdx, radius, density, motion, section),
          ),
        ),
      ],
    );
  }

  Widget _buildContent(PyramidTheme pt, bool isDark, int accentIdx,
      double radius, double density, double motion, String section) {
    return switch (section) {
      'appearance' => _AppearanceSection(
          pt: pt,
          isDark: isDark,
          accentIdx: accentIdx,
          radius: radius,
          density: density,
          motion: motion,
          ref: ref),
      'profile' => _ProfileSection(pt: pt),
      'notifications' => _NotificationsSection(pt: pt),
      'voice' => _VoiceSection(pt: pt),
      'keys' => _KeysSection(pt: pt),
      'privacy' => _PrivacySection(pt: pt),
      'sessions' => _SessionsSection(pt: pt),
      'encryption' => _EncryptionSection(pt: pt, ref: ref),
      'about' => _AboutSection(pt: pt),
      _ => _AppearanceSection(
          pt: pt,
          isDark: isDark,
          accentIdx: accentIdx,
          radius: radius,
          density: density,
          motion: motion,
          ref: ref),
    };
  }
}