import 'package:flutter/material.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'login_screen.dart';
import 'desktop_login_screen.dart';
import '../core/theme_manager.dart';
import 'privacy_policy_screen.dart'; // new import
import '../core/app_decoration.dart';

class SettingsScreen extends StatefulWidget {
  const SettingsScreen({Key? key}) : super(key: key);

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

class _SettingsScreenState extends State<SettingsScreen> {
  bool _notifications = true;
  String _appVersion = '1.2(p)';

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

  Future<void> _loadPreferences() async {
    final prefs = await SharedPreferences.getInstance();
    setState(() {
      _notifications = prefs.getBool('reminders_enabled') ?? true;
      // app version may come from pubspec or preferences; kept static otherwise
    });
  }

  Future<void> _saveNotifications(bool value) async {
    final prefs = await SharedPreferences.getInstance();
    await prefs.setBool('reminders_enabled', value);
    setState(() => _notifications = value);
  }

  Future<void> _confirmLogout() async {
    final should = await showDialog<bool>(
      context: context,
      builder: (ctx) {
        return AlertDialog(
          title: const Text('Logout'),
          content: const Text('Are you sure you want to logout? This will clear saved login data.'),
          actions: [
            TextButton(onPressed: () => Navigator.of(ctx).pop(false), child: const Text('Cancel')),
            ElevatedButton(onPressed: () => Navigator.of(ctx).pop(true), child: const Text('Logout')),
          ],
        );
      },
    );

    if (should == true) {
      await _performLogout();
    }
  }

  Future<void> _performLogout() async {
    final prefs = await SharedPreferences.getInstance();
    await prefs.remove('username');
    await prefs.remove('email');
    await prefs.remove('profileImage');

    // Decide which login screen to show depending on current window width
    final double width = MediaQuery.of(context).size.width;
    const double desktopBreakpoint = 820; // same breakpoint used elsewhere
    final bool isDesktop = width >= desktopBreakpoint;

    // Navigate and remove all previous routes
    Navigator.of(context).pushAndRemoveUntil(
      MaterialPageRoute(
        builder: (_) => isDesktop ? const DesktopLoginScreen() : const LoginScreen(),
      ),
      (route) => false,
    );
  }

  Widget _buildTile({required IconData icon, required String title, String? subtitle, VoidCallback? onTap}) {
    return Container(
      margin: const EdgeInsets.symmetric(vertical: 6),
      decoration: BoxDecoration(
        color: Theme.of(context).cardColor,
        borderRadius: BorderRadius.circular(12),
        boxShadow: const [BoxShadow(color: Colors.black12, blurRadius: 6, offset: Offset(0, 4))],
      ),
      child: ListTile(
        leading: Container(
          width: 44,
          height: 44,
          decoration: BoxDecoration(color: Theme.of(context).scaffoldBackgroundColor, borderRadius: BorderRadius.circular(10)),
          child: Icon(icon, color: const Color(0xFF0B63D6)),
        ),
        title: Text(title, style: const TextStyle(fontWeight: FontWeight.w600)),
        subtitle: subtitle != null ? Text(subtitle) : null,
        onTap: onTap,
        contentPadding: const EdgeInsets.symmetric(horizontal: 12, vertical: 8),
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    const primary = Color(0xFF0B63D6);

    return Scaffold(
      backgroundColor: Theme.of(context).scaffoldBackgroundColor,
      body: SafeArea(
        child: Column(
          children: [
            // Header
            Container(
              width: double.infinity,
              padding: const EdgeInsets.fromLTRB(20, 18, 20, 18),
              decoration: AppDecoration.blueGradient.copyWith(
                borderRadius: const BorderRadius.only(bottomLeft: Radius.circular(24), bottomRight: Radius.circular(24)),
              ),
              child: Row(
                children: [
                  const Expanded(child: Text('Settings', style: TextStyle(color: Colors.white, fontSize: 20, fontWeight: FontWeight.w600))),
                  InkWell(
                    onTap: () => ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('Help tapped (demo)'))),
                    child: Container(
                      width: 40,
                      height: 40,
                      decoration: BoxDecoration(color: Colors.white24, borderRadius: BorderRadius.circular(10)),
                      child: const Icon(Icons.help_outline, color: Colors.white),
                    ),
                  ),
                ],
              ),
            ),

            const SizedBox(height: 18),

            // Content
            Expanded(
              child: SingleChildScrollView(
                padding: const EdgeInsets.fromLTRB(18, 0, 18, 24),
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    // Account
                    const Text('Account', style: TextStyle(fontSize: 16, fontWeight: FontWeight.bold)),
                    const SizedBox(height: 12),
                    _buildTile(
                      icon: Icons.person,
                      title: 'Edit Profile',
                      subtitle: 'Change username, email or photo',
                      onTap: () {
                        ScaffoldMessenger.of(context).showSnackBar(const SnackBar(content: Text('Open Profile tab (demo)')));
                      },
                    ),
                    const SizedBox(height: 12),

                    // Preferences
                    const Text('Preferences', style: TextStyle(fontSize: 16, fontWeight: FontWeight.bold)),
                    const SizedBox(height: 12),

                    // Reminders switch wrapped in card-like container
                    Container(
                      margin: const EdgeInsets.symmetric(vertical: 6),
                      decoration: BoxDecoration(
                        color: Theme.of(context).cardColor,
                        borderRadius: BorderRadius.circular(12),
                        boxShadow: const [BoxShadow(color: Colors.black12, blurRadius: 6, offset: Offset(0, 4))],
                      ),
                      child: SwitchListTile(
                        tileColor: Theme.of(context).cardColor,
                        contentPadding: const EdgeInsets.symmetric(horizontal: 12, vertical: 4),
                        value: _notifications,
                        onChanged: (v) => _saveNotifications(v),
                        title: const Text('Reminders'),
                        secondary: const Icon(Icons.notifications, color: primary),
                      ),
                    ),

                    const SizedBox(height: 8),

                    // Dark Mode switch wrapped in card-like container and hooked to ThemeManager
                    Container(
                      margin: const EdgeInsets.symmetric(vertical: 6),
                      decoration: BoxDecoration(
                        color: Theme.of(context).cardColor,
                        borderRadius: BorderRadius.circular(12),
                        boxShadow: const [BoxShadow(color: Colors.black12, blurRadius: 6, offset: Offset(0, 4))],
                      ),
                      child: ValueListenableBuilder<ThemeMode>(
                        valueListenable: ThemeManager.themeMode,
                        builder: (context, mode, _) {
                          final isDark = mode == ThemeMode.dark;
                          return SwitchListTile(
                            tileColor: Theme.of(context).cardColor,
                            contentPadding: const EdgeInsets.symmetric(horizontal: 12, vertical: 4),
                            value: isDark,
                            onChanged: (v) => ThemeManager.setThemeMode(v ? ThemeMode.dark : ThemeMode.light),
                            title: const Text('Dark Mode'),
                            secondary: const Icon(Icons.dark_mode, color: primary),
                          );
                        },
                      ),
                    ),

                    const SizedBox(height: 18),

                    // About
                    const Text('About', style: TextStyle(fontSize: 16, fontWeight: FontWeight.bold)),
                    const SizedBox(height: 12),
                    _buildTile(icon: Icons.info_outline, title: 'App Version', subtitle: _appVersion, onTap: () {}),
                    const SizedBox(height: 12),

                    // Privacy Policy tile now navigates to PrivacyPolicyScreen
                    _buildTile(
                      icon: Icons.privacy_tip_outlined,
                      title: 'Privacy Policy',
                      subtitle: 'Demo app',
                      onTap: () {
                        Navigator.of(context).push(MaterialPageRoute(builder: (_) => const PrivacyPolicyScreen()));
                      },
                    ),

                    const SizedBox(height: 24),

                    // Logout area
                    Center(
                      child: Column(
                        children: [
                          ElevatedButton(
                            onPressed: _confirmLogout,
                            style: ElevatedButton.styleFrom(
                              backgroundColor: primary,
                              padding: const EdgeInsets.symmetric(horizontal: 28, vertical: 14),
                              shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(24)),
                            ),
                            child: const Text('Logout', style: TextStyle(color: Colors.white)),
                          ),
                          const SizedBox(height: 12),
                          const Text('Logging out will return you to the login screen.', style: TextStyle(color: Colors.black54, fontSize: 12)),
                        ],
                      ),
                    ),

                    const SizedBox(height: 32),
                  ],
                ),
              ),
            ),
          ],
        ),
      ),
    );
  }
}