import 'package:flutter/material.dart';
import '../models/models.dart';
import '../theme/app_theme.dart';
import '../widgets/widgets.dart' as w;
import 'splash_screen.dart';

class AdminScreen extends StatefulWidget {
  final UserModel usuario;
  const AdminScreen({super.key, required this.usuario});

  @override
  State<AdminScreen> createState() => _AdminScreenState();
}

class _AdminScreenState extends State<AdminScreen> {
  int _currentTab = 1;
  int _selectedSection = 0;

  final List<UserModel> _usuarios = [
    const UserModel(
      id: 'user-01',
      nombre: 'Ana',
      apellido: 'López',
      email: 'ana.lopez@rutaverde.com',
      telefono: '+52 461 111 2233',
    ),
    const UserModel(
      id: 'user-02',
      nombre: 'Luis',
      apellido: 'Ramírez',
      email: 'luis.ramirez@rutaverde.com',
      telefono: '+52 461 222 3344',
    ),
  ];

  final List<DriverModel> _conductores = [
    const DriverModel(
      id: 'driver-01',
      nombre: 'María Pérez',
      telefono: '+52 461 333 4455',
      placa: 'TRD-451',
      rutaAsignada: 'Ruta Norte',
    ),
    const DriverModel(
      id: 'driver-02',
      nombre: 'Jorge Torres',
      telefono: '+52 461 444 5566',
      placa: 'TRD-752',
      rutaAsignada: 'Ruta Sur',
    ),
  ];

  final List<TruckModel> _camiones = [
    const TruckModel(
      id: 'truck-01',
      placa: 'TRD-451',
      ruta: 'Ruta Norte',
      conductorId: 'driver-01',
      activo: true,
    ),
    const TruckModel(
      id: 'truck-02',
      placa: 'TRD-752',
      ruta: 'Ruta Sur',
      conductorId: 'driver-02',
      activo: false,
    ),
  ];

  void _selectSection(int index) {
    setState(() => _selectedSection = index);
  }

  void _onAddPressed() {
    switch (_selectedSection) {
      case 0:
        _showUserForm();
        break;
      case 1:
        _showDriverForm();
        break;
      case 2:
        _showTruckForm();
        break;
    }
  }

  void _showUserForm({UserModel? user}) {
    final nombre = TextEditingController(text: user?.nombre ?? '');
    final apellido = TextEditingController(text: user?.apellido ?? '');
    final email = TextEditingController(text: user?.email ?? '');
    final telefono = TextEditingController(text: user?.telefono ?? '');
    final formKey = GlobalKey<FormState>();

    showDialog(
      context: context,
      builder: (ctx) {
        return AlertDialog(
          title: Text(user == null ? 'Agregar usuario' : 'Editar usuario'),
          shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(AppTheme.radiusLg),
          ),
          content: Form(
            key: formKey,
            child: SingleChildScrollView(
              child: Column(
                mainAxisSize: MainAxisSize.min,
                children: [
                  _buildTextField('Nombre', nombre),
                  const SizedBox(height: 12),
                  _buildTextField('Apellido', apellido),
                  const SizedBox(height: 12),
                  _buildTextField('Email', email, keyboardType: TextInputType.emailAddress),
                  const SizedBox(height: 12),
                  _buildTextField('Teléfono', telefono, keyboardType: TextInputType.phone),
                ],
              ),
            ),
          ),
          actions: [
            TextButton(
              onPressed: () => Navigator.pop(ctx),
              child: const Text('Cancelar'),
            ),
            ElevatedButton(
              onPressed: () {
                if (!formKey.currentState!.validate()) return;
                final nuevo = UserModel(
                  id: user?.id ?? 'user-${DateTime.now().millisecondsSinceEpoch}',
                  nombre: nombre.text.trim(),
                  apellido: apellido.text.trim(),
                  email: email.text.trim(),
                  telefono: telefono.text.trim(),
                );
                setState(() {
                  if (user == null) {
                    _usuarios.add(nuevo);
                  } else {
                    final index = _usuarios.indexWhere((u) => u.id == user.id);
                    if (index != -1) {
                      _usuarios[index] = nuevo;
                    }
                  }
                });
                Navigator.pop(ctx);
              },
              child: const Text('Guardar'),
            ),
          ],
        );
      },
    );
  }

  void _showDriverForm({DriverModel? conductor}) {
    final nombre = TextEditingController(text: conductor?.nombre ?? '');
    final telefono = TextEditingController(text: conductor?.telefono ?? '');
    final placa = TextEditingController(text: conductor?.placa ?? '');
    final ruta = TextEditingController(text: conductor?.rutaAsignada ?? '');
    final formKey = GlobalKey<FormState>();

    showDialog(
      context: context,
      builder: (ctx) {
        return AlertDialog(
          title: Text(conductor == null ? 'Agregar conductor' : 'Editar conductor'),
          shape: RoundedRectangleBorder(
            borderRadius: BorderRadius.circular(AppTheme.radiusLg),
          ),
          content: Form(
            key: formKey,
            child: SingleChildScrollView(
              child: Column(
                mainAxisSize: MainAxisSize.min,
                children: [
                  _buildTextField('Nombre', nombre),
                  const SizedBox(height: 12),
                  _buildTextField('Teléfono', telefono, keyboardType: TextInputType.phone),
                  const SizedBox(height: 12),
                  _buildTextField('Placa', placa),
                  const SizedBox(height: 12),
                  _buildTextField('Ruta asignada', ruta),
                ],
              ),
            ),
          ),
          actions: [
            TextButton(
              onPressed: () => Navigator.pop(ctx),
              child: const Text('Cancelar'),
            ),
            ElevatedButton(
              onPressed: () {
                if (!formKey.currentState!.validate()) return;
                final nuevo = DriverModel(
                  id: conductor?.id ?? 'driver-${DateTime.now().millisecondsSinceEpoch}',
                  nombre: nombre.text.trim(),
                  telefono: telefono.text.trim(),
                  placa: placa.text.trim(),
                  rutaAsignada: ruta.text.trim(),
                );
                setState(() {
                  if (conductor == null) {
                    _conductores.add(nuevo);
                  } else {
                    final index = _conductores.indexWhere((d) => d.id == conductor.id);
                    if (index != -1) {
                      _conductores[index] = nuevo;
                    }
                  }
                });
                Navigator.pop(ctx);
              },
              child: const Text('Guardar'),
            ),
          ],
        );
      },
    );
  }

  void _showTruckForm({TruckModel? camion}) {
    final placa = TextEditingController(text: camion?.placa ?? '');
    final ruta = TextEditingController(text: camion?.ruta ?? '');
    var activo = camion?.activo ?? true;
    String conductorId = camion?.conductorId ?? _conductores.first.id;
    final formKey = GlobalKey<FormState>();

    showDialog(
      context: context,
      builder: (ctx) {
        return StatefulBuilder(
          builder: (ctx, setStateDialog) {
            return AlertDialog(
              title: Text(camion == null ? 'Agregar camión' : 'Editar camión'),
              shape: RoundedRectangleBorder(
                borderRadius: BorderRadius.circular(AppTheme.radiusLg),
              ),
              content: Form(
                key: formKey,
                child: SingleChildScrollView(
                  child: Column(
                    mainAxisSize: MainAxisSize.min,
                    children: [
                      _buildTextField('Placa', placa),
                      const SizedBox(height: 12),
                      _buildTextField('Ruta', ruta),
                      const SizedBox(height: 12),
                      DropdownButtonFormField<String>(
                        initialValue: conductorId,
                        decoration: InputDecoration(
                          labelText: 'Conductor',
                          border: OutlineInputBorder(
                            borderRadius: BorderRadius.circular(AppTheme.radiusMd),
                          ),
                        ),
                        items: _conductores
                            .map((d) => DropdownMenuItem(
                                  value: d.id,
                                  child: Text(d.nombre),
                                ))
                            .toList(),
                        onChanged: (value) {
                          if (value != null) {
                            setStateDialog(() => conductorId = value);
                          }
                        },
                      ),
                      const SizedBox(height: 16),
                      Row(
                        mainAxisAlignment: MainAxisAlignment.spaceBetween,
                        children: [
                          const Text('Activo', style: TextStyle(fontWeight: FontWeight.w600)),
                          Switch(
                            value: activo,
                            onChanged: (value) => setStateDialog(() => activo = value),
                          ),
                        ],
                      ),
                    ],
                  ),
                ),
              ),
              actions: [
                TextButton(
                  onPressed: () => Navigator.pop(ctx),
                  child: const Text('Cancelar'),
                ),
                ElevatedButton(
                  onPressed: () {
                    if (!formKey.currentState!.validate()) return;
                    final nuevo = TruckModel(
                      id: camion?.id ?? 'truck-${DateTime.now().millisecondsSinceEpoch}',
                      placa: placa.text.trim(),
                      ruta: ruta.text.trim(),
                      conductorId: conductorId,
                      activo: activo,
                    );
                    setState(() {
                      if (camion == null) {
                        _camiones.add(nuevo);
                      } else {
                        final index = _camiones.indexWhere((t) => t.id == camion.id);
                        if (index != -1) {
                          _camiones[index] = nuevo;
                        }
                      }
                    });
                    Navigator.pop(ctx);
                  },
                  child: const Text('Guardar'),
                ),
              ],
            );
          },
        );
      },
    );
  }

  Widget _buildTextField(String label, TextEditingController controller,
      {TextInputType keyboardType = TextInputType.text}) {
    return TextFormField(
      controller: controller,
      keyboardType: keyboardType,
      validator: (value) {
        if (value == null || value.trim().isEmpty) {
          return 'Debe completar este campo';
        }
        return null;
      },
      decoration: InputDecoration(
        labelText: label,
        border: OutlineInputBorder(
          borderRadius: BorderRadius.circular(AppTheme.radiusMd),
        ),
      ),
    );
  }

  void _confirmDelete<T>(T item, List<T> lista, String tipo) {
    showDialog(
      context: context,
      builder: (ctx) {
        return AlertDialog(
          title: Text('Eliminar $tipo'),
          content: Text('¿Seguro que deseas eliminar este $tipo?'),
          actions: [
            TextButton(
              onPressed: () => Navigator.pop(ctx),
              child: const Text('Cancelar'),
            ),
            TextButton(
              onPressed: () {
                setState(() => lista.remove(item));
                Navigator.pop(ctx);
              },
              style: TextButton.styleFrom(foregroundColor: AppTheme.danger),
              child: const Text('Eliminar'),
            ),
          ],
        );
      },
    );
  }

  @override
  Widget build(BuildContext context) {
    if (!widget.usuario.isAdmin) {
      return Scaffold(
        backgroundColor: AppTheme.background,
        appBar: AppBar(title: const Text('Acceso denegado')),
        body: Center(
          child: Padding(
            padding: const EdgeInsets.symmetric(horizontal: 24),
            child: Column(
              mainAxisSize: MainAxisSize.min,
              children: [
                const Text(
                  'Este panel solo está disponible para administradores.',
                  textAlign: TextAlign.center,
                  style: TextStyle(fontSize: 16, color: AppTheme.textPrimary),
                ),
                const SizedBox(height: 18),
                ElevatedButton(
                  onPressed: () {
                    Navigator.pushAndRemoveUntil(
                      context,
                      MaterialPageRoute(builder: (_) => const SplashScreen()),
                      (_) => false,
                    );
                  },
                  child: const Text('Volver al inicio'),
                ),
              ],
            ),
          ),
        ),
      );
    }

    return Scaffold(
      backgroundColor: AppTheme.background,
      appBar: AppBar(
        title: Text(_currentTab == 0 ? 'Mi perfil' : 'Panel administrador'),
        actions: _currentTab == 1
            ? [
                IconButton(
                  icon: const Icon(Icons.add),
                  onPressed: _onAddPressed,
                  tooltip: 'Agregar',
                ),
              ]
            : null,
      ),
      body: IndexedStack(
        index: _currentTab,
        children: [
          _buildAdminProfile(),
          _buildAdminBody(),
        ],
      ),
      bottomNavigationBar: BottomNavigationBar(
        currentIndex: _currentTab,
        onTap: (value) => setState(() => _currentTab = value),
        items: const [
          BottomNavigationBarItem(
            icon: Icon(Icons.person_outline),
            label: 'Perfil',
          ),
          BottomNavigationBarItem(
            icon: Icon(Icons.admin_panel_settings_outlined),
            label: 'Admin',
          ),
        ],
      ),
    );
  }

  Widget _buildAdminBody() {
    return Column(
      children: [
        Padding(
          padding: const EdgeInsets.all(16),
          child: Row(
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: [
              _buildSectionButton('Usuarios', 0),
              _buildSectionButton('Conductores', 1),
              _buildSectionButton('Camiones', 2),
            ],
          ),
        ),
        Expanded(
          child: Padding(
            padding: const EdgeInsets.symmetric(horizontal: 16),
            child: _buildCurrentSection(),
          ),
        ),
      ],
    );
  }

  Widget _buildAdminProfile() {
    return SingleChildScrollView(
      padding: const EdgeInsets.all(16),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          w.AppCard(
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                Row(
                  children: [
                    Container(
                      width: 56,
                      height: 56,
                      decoration: BoxDecoration(
                        color: AppTheme.primaryLight,
                        shape: BoxShape.circle,
                      ),
                      child: Center(
                        child: Text(
                          widget.usuario.iniciales,
                          style: const TextStyle(
                            fontSize: 20,
                            fontWeight: FontWeight.w700,
                            color: AppTheme.primaryDark,
                          ),
                        ),
                      ),
                    ),
                    const SizedBox(width: 16),
                    Expanded(
                      child: Column(
                        crossAxisAlignment: CrossAxisAlignment.start,
                        children: [
                          Text(widget.usuario.nombreCompleto,
                              style: const TextStyle(
                                fontSize: 18,
                                fontWeight: FontWeight.w700,
                              )),
                          const SizedBox(height: 6),
                          Text(widget.usuario.email,
                              style: const TextStyle(color: AppTheme.textSecondary)),
                          const SizedBox(height: 2),
                          Text(widget.usuario.telefono,
                              style: const TextStyle(color: AppTheme.textSecondary)),
                        ],
                      ),
                    ),
                  ],
                ),
                const SizedBox(height: 16),
                Wrap(
                  spacing: 8,
                  children: [
                    w.StatusBadge.green('Administrador'),
                    w.StatusBadge.gray(widget.usuario.role == UserRole.admin ? 'Admin' : 'Usuario'),
                  ],
                ),
              ],
            ),
          ),
          const SizedBox(height: 20),
          w.SectionTitle(title: 'Cuenta'),
          w.MenuTile(
            icon: Icons.person_outline,
            title: 'Editar perfil',
            subtitle: widget.usuario.nombreCompleto,
            onTap: () {},
          ),
          w.MenuTile(
            icon: Icons.email_outlined,
            title: 'Email',
            subtitle: widget.usuario.email,
            onTap: () {},
          ),
          w.MenuTile(
            icon: Icons.phone_outlined,
            title: 'Teléfono',
            subtitle: widget.usuario.telefono,
            onTap: () {},
          ),
        ],
      ),
    );
  }

  Widget _buildSectionButton(String label, int index) {
    final selected = _selectedSection == index;
    return Expanded(
      child: Padding(
        padding: const EdgeInsets.symmetric(horizontal: 4),
        child: ElevatedButton(
          onPressed: () => _selectSection(index),
          style: ElevatedButton.styleFrom(
            backgroundColor: selected ? AppTheme.primary : AppTheme.surface,
            foregroundColor: selected ? Colors.white : AppTheme.textPrimary,
            padding: const EdgeInsets.symmetric(vertical: 12),
            shape: RoundedRectangleBorder(
              borderRadius: BorderRadius.circular(AppTheme.radiusMd),
            ),
            elevation: selected ? 2 : 0,
          ),
          child: Text(label, textAlign: TextAlign.center),
        ),
      ),
    );
  }

  Widget _buildCurrentSection() {
    switch (_selectedSection) {
      case 0:
        return _buildUsuarioSection();
      case 1:
        return _buildDriverSection();
      default:
        return _buildTruckSection();
    }
  }

  Widget _buildUsuarioSection() {
    if (_usuarios.isEmpty) {
      return const Center(child: Text('No hay usuarios registrados.'));
    }
    return ListView.builder(
      padding: const EdgeInsets.only(bottom: 16),
      itemCount: _usuarios.length,
      itemBuilder: (context, index) {
        final usuario = _usuarios[index];
        return w.AppCard(
          padding: const EdgeInsets.all(16),
          child: Row(
            children: [
              Expanded(
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Text(usuario.nombreCompleto,
                        style: const TextStyle(
                          fontSize: 15,
                          fontWeight: FontWeight.w700,
                        )),
                    const SizedBox(height: 6),
                    Text(usuario.email,
                        style: const TextStyle(color: AppTheme.textSecondary)),
                    const SizedBox(height: 2),
                    Text(usuario.telefono,
                        style: const TextStyle(color: AppTheme.textSecondary)),
                  ],
                ),
              ),
              IconButton(
                icon: const Icon(Icons.edit_outlined),
                onPressed: () => _showUserForm(user: usuario),
              ),
              IconButton(
                icon: const Icon(Icons.delete_outline, color: AppTheme.danger),
                onPressed: () => _confirmDelete(usuario, _usuarios, 'usuario'),
              ),
            ],
          ),
        );
      },
    );
  }

  Widget _buildDriverSection() {
    if (_conductores.isEmpty) {
      return const Center(child: Text('No hay conductores registrados.'));
    }
    return ListView.builder(
      padding: const EdgeInsets.only(bottom: 16),
      itemCount: _conductores.length,
      itemBuilder: (context, index) {
        final conductor = _conductores[index];
        return w.AppCard(
          padding: const EdgeInsets.all(16),
          child: Row(
            children: [
              Expanded(
                child: Column(
                  crossAxisAlignment: CrossAxisAlignment.start,
                  children: [
                    Text(conductor.nombre,
                        style: const TextStyle(
                          fontSize: 15,
                          fontWeight: FontWeight.w700,
                        )),
                    const SizedBox(height: 6),
                    Text(conductor.telefono,
                        style: const TextStyle(color: AppTheme.textSecondary)),
                    const SizedBox(height: 2),
                    Text('${conductor.placa} · ${conductor.rutaAsignada}',
                        style: const TextStyle(color: AppTheme.textSecondary)),
                  ],
                ),
              ),
              IconButton(
                icon: const Icon(Icons.edit_outlined),
                onPressed: () => _showDriverForm(conductor: conductor),
              ),
              IconButton(
                icon: const Icon(Icons.delete_outline, color: AppTheme.danger),
                onPressed: () => _confirmDelete(conductor, _conductores, 'conductor'),
              ),
            ],
          ),
        );
      },
    );
  }

  Widget _buildTruckSection() {
    if (_camiones.isEmpty) {
      return const Center(child: Text('No hay camiones registrados.'));
    }
    return ListView.builder(
      padding: const EdgeInsets.only(bottom: 16),
      itemCount: _camiones.length,
      itemBuilder: (context, index) {
        final camion = _camiones[index];
        final conductor = _conductores.firstWhere(
          (d) => d.id == camion.conductorId,
          orElse: () => const DriverModel(
            id: 'none',
            nombre: 'Sin conductor',
            telefono: '-',
            placa: '-',
            rutaAsignada: '-',
          ),
        );
        return w.AppCard(
          padding: const EdgeInsets.all(16),
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              Row(
                children: [
                  Expanded(
                    child: Column(
                      crossAxisAlignment: CrossAxisAlignment.start,
                      children: [
                        Text(camion.placa,
                            style: const TextStyle(
                              fontSize: 15,
                              fontWeight: FontWeight.w700,
                            )),
                        const SizedBox(height: 6),
                        Text(camion.ruta,
                            style:
                                const TextStyle(color: AppTheme.textSecondary)),
                      ],
                    ),
                  ),
                  w.StatusBadge.gray(camion.activo ? 'Activo' : 'Inactivo'),
                ],
              ),
              const SizedBox(height: 10),
              Text('Conductor: ${conductor.nombre}',
                  style: const TextStyle(color: AppTheme.textSecondary)),
              const SizedBox(height: 8),
              Row(
                children: [
                  TextButton.icon(
                    icon: const Icon(Icons.edit_outlined),
                    label: const Text('Editar'),
                    onPressed: () => _showTruckForm(camion: camion),
                  ),
                  const SizedBox(width: 8),
                  TextButton.icon(
                    icon: const Icon(Icons.delete_outline, color: AppTheme.danger),
                    label: const Text('Eliminar',
                        style: TextStyle(color: AppTheme.danger)),
                    onPressed: () => _confirmDelete(camion, _camiones, 'camión'),
                  ),
                ],
              ),
            ],
          ),
        );
      },
    );
  }
}