'use client';

import { useState, useEffect, useCallback, useMemo } from 'react';
import { useRouter } from 'next/navigation';
import { adminService } from '@/services/admin.service';
import { User, CreateEmployeeData, UpdateUserData, PaginatedResponse } from '@/types';
import { Pagination } from '@/components/ui';

export default function UserManagement() {
  const router = useRouter();
  const [users, setUsers] = useState<User[]>([]);
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState<string | null>(null);
  const [page, setPage] = useState(1);
  const [totalPages, setTotalPages] = useState(1);
  const [filterRole, setFilterRole] = useState<string>('');
  const [filterStatus, setFilterStatus] = useState<string>('');
  const [searchQuery, setSearchQuery] = useState<string>('');

  // Filtrage côté client par nom/email
  const filteredUsers = useMemo(() => {
    if (!searchQuery.trim()) return users;
    const query = searchQuery.toLowerCase().trim();
    return users.filter(user =>
      user.firstName?.toLowerCase().includes(query) ||
      user.lastName?.toLowerCase().includes(query) ||
      user.email?.toLowerCase().includes(query) ||
      `${user.firstName} ${user.lastName}`.toLowerCase().includes(query)
    );
  }, [users, searchQuery]);

  // Modals
  const [isCreateEmployeeModalOpen, setIsCreateEmployeeModalOpen] = useState(false);
  const [isEditUserModalOpen, setIsEditUserModalOpen] = useState(false);
  const [editingUser, setEditingUser] = useState<User | null>(null);

  // Form data
  const [employeeFormData, setEmployeeFormData] = useState<CreateEmployeeData>({
    email: '',
    password: '',
    firstName: '',
    lastName: '',
  });

  const [userFormData, setUserFormData] = useState<UpdateUserData>({});

  const loadUsers = useCallback(async () => {
    try {
      setLoading(true);
      setError(null);
      const filters: any = {};
      if (filterRole) filters.role = filterRole;
      if (filterStatus) filters.isActive = filterStatus === 'active';

      const response: PaginatedResponse<User> = await adminService.getAllUsers(
        page,
        100, // Charger plus pour le filtrage côté client
        Object.keys(filters).length > 0 ? filters : undefined
      );
      setUsers(response.data || []);
      setTotalPages(response.totalPages || 1);
    } catch (err: any) {
      setError(err.message || 'Erreur lors du chargement des utilisateurs');
      setUsers([]);
    } finally {
      setLoading(false);
    }
  }, [page, filterRole, filterStatus]);

  useEffect(() => {
    loadUsers();
  }, [loadUsers]);

  const handleCreateEmployee = async (e: React.FormEvent) => {
    e.preventDefault();
    try {
      await adminService.createEmployee(employeeFormData);
      setIsCreateEmployeeModalOpen(false);
      setEmployeeFormData({ email: '', password: '', firstName: '', lastName: '' });
      loadUsers();
    } catch (err: any) {
      alert(err.message || 'Erreur lors de la création de l\'employé');
    }
  };

  const handleEditUser = (user: User) => {
    setEditingUser(user);
    setUserFormData({
      role: user.role,
      firstName: user.firstName,
      lastName: user.lastName,
    });
    setIsEditUserModalOpen(true);
  };

  const handleUpdateUser = async (e: React.FormEvent) => {
    e.preventDefault();
    if (!editingUser) return;

    try {
      await adminService.updateUser(editingUser.id, userFormData);
      setIsEditUserModalOpen(false);
      setEditingUser(null);
      loadUsers();
    } catch (err: any) {
      alert(err.message || 'Erreur lors de la modification de l\'utilisateur');
    }
  };

  const handleToggleUserStatus = async (user: User) => {
    const action = user.isActive ? 'désactiver' : 'réactiver';
    if (!confirm(`Êtes-vous sûr de vouloir ${action} cet utilisateur ?`)) return;

    try {
      await adminService.updateUser(user.id, { isActive: !user.isActive });
      loadUsers();
    } catch (err: any) {
      alert(err.message || `Erreur lors de la ${action}ation`);
    }
  };

  const getRoleBadgeColor = (role: string) => {
    switch (role) {
      case 'ADMIN':
        return 'bg-red-100 text-red-800';
      case 'EMPLOYEE':
        return 'bg-blue-100 text-blue-800';
      case 'CLIENT':
        return 'bg-green-100 text-green-800';
      default:
        return 'bg-gray-100 text-gray-800';
    }
  };

  if (loading && users.length === 0) {
    return <div className="text-center py-8">Chargement des utilisateurs...</div>;
  }

  return (
    <div className="p-6">
      <div className="flex justify-between items-center mb-6">
        <h1 className="text-2xl font-bold">Gestion des Utilisateurs</h1>
        <button
          onClick={() => setIsCreateEmployeeModalOpen(true)}
          className="bg-blue-600 text-white px-4 py-2 rounded-lg hover:bg-blue-700"
        >
          Créer un employé
        </button>
      </div>

      {error && (
        <div className="bg-red-100 border border-red-400 text-red-700 px-4 py-3 rounded mb-4">
          {error}
        </div>
      )}

      {/* Filtres */}
      <div className="mb-4 flex flex-wrap gap-4">
        <div className="flex-1 min-w-[250px]">
          <input
            type="text"
            placeholder="Rechercher par nom ou email..."
            value={searchQuery}
            onChange={(e) => setSearchQuery(e.target.value)}
            className="w-full border rounded px-3 py-2"
          />
        </div>
        <select
          value={filterRole}
          onChange={(e) => {
            setFilterRole(e.target.value);
            setPage(1);
          }}
          className="border rounded px-3 py-2"
        >
          <option value="">Tous les rôles</option>
          <option value="CLIENT">Clients</option>
          <option value="EMPLOYEE">Employés</option>
          <option value="ADMIN">Administrateurs</option>
        </select>
        <select
          value={filterStatus}
          onChange={(e) => {
            setFilterStatus(e.target.value);
            setPage(1);
          }}
          className="border rounded px-3 py-2"
        >
          <option value="">Tous les statuts</option>
          <option value="active">Actifs</option>
          <option value="inactive">Inactifs (archivés)</option>
        </select>
      </div>

      {/* Table des utilisateurs */}
      <div className="bg-white rounded-lg shadow overflow-hidden">
        <table className="min-w-full divide-y divide-gray-200">
          <thead className="bg-gray-50">
            <tr>
              <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">
                Utilisateur
              </th>
              <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">
                Email
              </th>
              <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">
                Rôle
              </th>
              <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">
                Statut
              </th>
              <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">
                Date création
              </th>
              <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">
                Actions
              </th>
            </tr>
          </thead>
          <tbody className="bg-white divide-y divide-gray-200">
            {filteredUsers.length === 0 ? (
              <tr>
                <td colSpan={6} className="px-6 py-8 text-center text-gray-500">
                  {searchQuery ? 'Aucun résultat pour cette recherche' : 'Aucun utilisateur trouvé'}
                </td>
              </tr>
            ) : (
              filteredUsers.map((user) => (
                <tr key={user.id} className="hover:bg-gray-50">
                <td className="px-6 py-4 whitespace-nowrap">
                  <div className="text-sm font-medium text-gray-900">
                    {user.firstName} {user.lastName}
                  </div>
                </td>
                <td className="px-6 py-4 whitespace-nowrap">
                  <div className="text-sm text-gray-500">{user.email}</div>
                </td>
                <td className="px-6 py-4 whitespace-nowrap">
                  <span className={`px-2 inline-flex text-xs leading-5 font-semibold rounded-full ${getRoleBadgeColor(user.role)}`}>
                    {user.role}
                  </span>
                </td>
                <td className="px-6 py-4 whitespace-nowrap">
                  <span className={`px-2 inline-flex text-xs leading-5 font-semibold rounded-full ${user.isActive !== false ? 'bg-green-100 text-green-800' : 'bg-red-100 text-red-800'}`}>
                    {user.isActive !== false ? 'Actif' : 'Inactif'}
                  </span>
                </td>
                <td className="px-6 py-4 whitespace-nowrap text-sm text-gray-500">
                  {new Date(user.createdAt).toLocaleDateString('fr-FR')}
                </td>
                <td className="px-6 py-4 whitespace-nowrap text-sm font-medium">
                  <button
                    onClick={() => router.push(`/admin/utilisateurs/${user.id}`)}
                    className="text-blue-600 hover:text-blue-900"
                  >
                    Détails
                  </button>
                </td>
              </tr>
            ))
            )}
          </tbody>
        </table>
      </div>

      {/* Pagination */}
      <Pagination
        currentPage={page}
        totalPages={totalPages}
        onPageChange={setPage}
        showPageNumbers={false}
      />

      {/* Modal créer employé */}
      {isCreateEmployeeModalOpen && (
        <div className="fixed inset-0 bg-black bg-opacity-50 flex items-center justify-center z-50">
          <div className="bg-white rounded-lg p-6 max-w-md w-full">
            <h2 className="text-xl font-bold mb-4">Créer un employé</h2>
            <form onSubmit={handleCreateEmployee} className="space-y-4">
              <div>
                <label className="block text-sm font-medium mb-1">Email</label>
                <input
                  type="email"
                  value={employeeFormData.email}
                  onChange={(e) => setEmployeeFormData({ ...employeeFormData, email: e.target.value })}
                  className="w-full border rounded px-3 py-2"
                  required
                />
              </div>
              <div>
                <label className="block text-sm font-medium mb-1">Mot de passe</label>
                <input
                  type="password"
                  value={employeeFormData.password}
                  onChange={(e) => setEmployeeFormData({ ...employeeFormData, password: e.target.value })}
                  className="w-full border rounded px-3 py-2"
                  required
                />
              </div>
              <div>
                <label className="block text-sm font-medium mb-1">Prénom</label>
                <input
                  type="text"
                  value={employeeFormData.firstName}
                  onChange={(e) => setEmployeeFormData({ ...employeeFormData, firstName: e.target.value })}
                  className="w-full border rounded px-3 py-2"
                  required
                />
              </div>
              <div>
                <label className="block text-sm font-medium mb-1">Nom</label>
                <input
                  type="text"
                  value={employeeFormData.lastName}
                  onChange={(e) => setEmployeeFormData({ ...employeeFormData, lastName: e.target.value })}
                  className="w-full border rounded px-3 py-2"
                  required
                />
              </div>
              <div className="flex gap-2 pt-4">
                <button
                  type="submit"
                  className="flex-1 bg-blue-600 text-white px-4 py-2 rounded hover:bg-blue-700"
                >
                  Créer
                </button>
                <button
                  type="button"
                  onClick={() => setIsCreateEmployeeModalOpen(false)}
                  className="flex-1 bg-gray-300 text-gray-700 px-4 py-2 rounded hover:bg-gray-400"
                >
                  Annuler
                </button>
              </div>
            </form>
          </div>
        </div>
      )}

      {/* Modal modifier utilisateur */}
      {isEditUserModalOpen && editingUser && (
        <div className="fixed inset-0 bg-black bg-opacity-50 flex items-center justify-center z-50">
          <div className="bg-white rounded-lg p-6 max-w-md w-full">
            <h2 className="text-xl font-bold mb-4">Modifier l'utilisateur</h2>
            <form onSubmit={handleUpdateUser} className="space-y-4">
              <div>
                <label className="block text-sm font-medium mb-1">Rôle</label>
                <select
                  value={userFormData.role}
                  onChange={(e) => setUserFormData({ ...userFormData, role: e.target.value as 'CLIENT' | 'EMPLOYEE' | 'ADMIN' })}
                  className="w-full border rounded px-3 py-2"
                >
                  <option value="CLIENT">Client</option>
                  <option value="EMPLOYEE">Employé</option>
                  <option value="ADMIN">Administrateur</option>
                </select>
              </div>
              <div className="flex gap-2 pt-4">
                <button
                  type="submit"
                  className="flex-1 bg-blue-600 text-white px-4 py-2 rounded hover:bg-blue-700"
                >
                  Mettre à jour
                </button>
                <button
                  type="button"
                  onClick={() => setIsEditUserModalOpen(false)}
                  className="flex-1 bg-gray-300 text-gray-700 px-4 py-2 rounded hover:bg-gray-400"
                >
                  Annuler
                </button>
              </div>
            </form>
          </div>
        </div>
      )}
    </div>
  );
}