'use client';

import { useEffect, useState, useCallback } from 'react';
import { 
  Search, 
  Plus, 
  MoreVertical,
  Edit,
  Trash2,
  UserCheck,
  UserX,
  Crown,
} from 'lucide-react';
import { 
  fetchAdminUsers, 
  createAdminUser, 
  updateAdminUser, 
  deleteAdminUser 
} from '@/lib/api';
import type { AdminUser, UserRole, UserTier } from '@/lib/types';

interface UserModalProps {
  user?: AdminUser;
  onClose: () => void;
  onSave: (data: { email: string; password?: string; displayName: string; role: UserRole; tier: UserTier }) => void;
}

function UserModal({ user, onClose, onSave }: UserModalProps) {
  const [email, setEmail] = useState(user?.email || '');
  const [password, setPassword] = useState('');
  const [displayName, setDisplayName] = useState(user?.displayName || '');
  const [role, setRole] = useState<UserRole>(user?.role || 'user');
  const [tier, setTier] = useState<UserTier>(user?.tier || 'free');

  const handleSubmit = (e: React.FormEvent) => {
    e.preventDefault();
    onSave({ 
      email, 
      password: password || undefined, 
      displayName, 
      role, 
      tier 
    });
  };

  return (
    <div className="fixed inset-0 bg-black/50 flex items-center justify-center z-50">
      <div className="bg-surface rounded-xl p-6 w-full max-w-md">
        <h2 className="text-xl font-bold text-primary mb-4">
          {user ? 'Редактировать пользователя' : 'Новый пользователь'}
        </h2>
        <form onSubmit={handleSubmit} className="space-y-4">
          <div>
            <label className="block text-sm text-secondary mb-1">Email</label>
            <input
              type="email"
              value={email}
              onChange={(e) => setEmail(e.target.value)}
              className="w-full px-3 py-2 bg-base border border-border/50 rounded-lg text-primary focus:outline-none focus:border-primary"
              required
            />
          </div>
          {!user && (
            <div>
              <label className="block text-sm text-secondary mb-1">Пароль</label>
              <input
                type="password"
                value={password}
                onChange={(e) => setPassword(e.target.value)}
                className="w-full px-3 py-2 bg-base border border-border/50 rounded-lg text-primary focus:outline-none focus:border-primary"
                required={!user}
              />
            </div>
          )}
          <div>
            <label className="block text-sm text-secondary mb-1">Имя</label>
            <input
              type="text"
              value={displayName}
              onChange={(e) => setDisplayName(e.target.value)}
              className="w-full px-3 py-2 bg-base border border-border/50 rounded-lg text-primary focus:outline-none focus:border-primary"
              required
            />
          </div>
          <div className="grid grid-cols-2 gap-4">
            <div>
              <label className="block text-sm text-secondary mb-1">Роль</label>
              <select
                value={role}
                onChange={(e) => setRole(e.target.value as UserRole)}
                className="w-full px-3 py-2 bg-base border border-border/50 rounded-lg text-primary focus:outline-none focus:border-primary"
              >
                <option value="user">Пользователь</option>
                <option value="admin">Администратор</option>
              </select>
            </div>
            <div>
              <label className="block text-sm text-secondary mb-1">Тариф</label>
              <select
                value={tier}
                onChange={(e) => setTier(e.target.value as UserTier)}
                className="w-full px-3 py-2 bg-base border border-border/50 rounded-lg text-primary focus:outline-none focus:border-primary"
              >
                <option value="free">Free</option>
                <option value="pro">Pro</option>
                <option value="business">Business</option>
              </select>
            </div>
          </div>
          <div className="flex gap-3 pt-4">
            <button
              type="button"
              onClick={onClose}
              className="flex-1 px-4 py-2 border border-border/50 rounded-lg text-secondary hover:bg-base transition-colors"
            >
              Отмена
            </button>
            <button
              type="submit"
              className="flex-1 px-4 py-2 bg-primary text-white rounded-lg hover:bg-primary/90 transition-colors"
            >
              Сохранить
            </button>
          </div>
        </form>
      </div>
    </div>
  );
}

export default function AdminUsersPage() {
  const [users, setUsers] = useState<AdminUser[]>([]);
  const [total, setTotal] = useState(0);
  const [page, setPage] = useState(1);
  const [search, setSearch] = useState('');
  const [loading, setLoading] = useState(true);
  const [modalUser, setModalUser] = useState<AdminUser | null | undefined>(undefined);
  const [activeMenu, setActiveMenu] = useState<string | null>(null);

  const loadUsers = useCallback(async () => {
    setLoading(true);
    try {
      const data = await fetchAdminUsers(page, 20, search || undefined);
      setUsers(data.users);
      setTotal(data.total);
    } catch (err) {
      console.error('Failed to load users:', err);
    } finally {
      setLoading(false);
    }
  }, [page, search]);

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

  const handleSave = async (data: { email: string; password?: string; displayName: string; role: UserRole; tier: UserTier }) => {
    try {
      if (modalUser) {
        await updateAdminUser(modalUser.id, data);
      } else {
        await createAdminUser({ ...data, password: data.password || '' });
      }
      setModalUser(undefined);
      loadUsers();
    } catch (err) {
      console.error('Failed to save user:', err);
    }
  };

  const handleDelete = async (id: string) => {
    if (!confirm('Удалить пользователя?')) return;
    try {
      await deleteAdminUser(id);
      loadUsers();
    } catch (err) {
      console.error('Failed to delete user:', err);
    }
  };

  const handleToggleActive = async (user: AdminUser) => {
    try {
      await updateAdminUser(user.id, { isActive: !user.isActive });
      loadUsers();
    } catch (err) {
      console.error('Failed to toggle user:', err);
    }
  };

  const totalPages = Math.ceil(total / 20);

  return (
    <div className="space-y-6">
      <div className="flex items-center justify-between">
        <div>
          <h1 className="text-2xl font-bold text-primary">Пользователи</h1>
          <p className="text-muted">Управление пользователями платформы</p>
        </div>
        <button
          onClick={() => setModalUser(null)}
          className="flex items-center gap-2 px-4 py-2 bg-primary text-white rounded-lg hover:bg-primary/90 transition-colors"
        >
          <Plus className="w-4 h-4" />
          Добавить
        </button>
      </div>

      <div className="bg-surface rounded-xl border border-border/30">
        <div className="p-4 border-b border-border/30">
          <div className="relative">
            <Search className="absolute left-3 top-1/2 -translate-y-1/2 w-4 h-4 text-muted" />
            <input
              type="text"
              placeholder="Поиск по email или имени..."
              value={search}
              onChange={(e) => {
                setSearch(e.target.value);
                setPage(1);
              }}
              className="w-full pl-10 pr-4 py-2 bg-base border border-border/50 rounded-lg text-primary placeholder:text-muted focus:outline-none focus:border-primary"
            />
          </div>
        </div>

        {loading ? (
          <div className="flex items-center justify-center h-64">
            <div className="animate-spin rounded-full h-8 w-8 border-b-2 border-primary" />
          </div>
        ) : (
          <>
            <div className="overflow-x-auto">
              <table className="w-full">
                <thead>
                  <tr className="border-b border-border/30">
                    <th className="text-left px-4 py-3 text-sm font-medium text-muted">Пользователь</th>
                    <th className="text-left px-4 py-3 text-sm font-medium text-muted">Роль</th>
                    <th className="text-left px-4 py-3 text-sm font-medium text-muted">Тариф</th>
                    <th className="text-left px-4 py-3 text-sm font-medium text-muted">Статус</th>
                    <th className="text-left px-4 py-3 text-sm font-medium text-muted">Создан</th>
                    <th className="w-12"></th>
                  </tr>
                </thead>
                <tbody>
                  {users.map((user) => (
                    <tr key={user.id} className="border-b border-border/20 hover:bg-base/50">
                      <td className="px-4 py-3">
                        <div className="flex items-center gap-3">
                          <div className="w-10 h-10 rounded-full bg-primary/10 flex items-center justify-center">
                            {user.avatarUrl ? (
                              <img src={user.avatarUrl} alt="" className="w-10 h-10 rounded-full" />
                            ) : (
                              <span className="text-primary font-medium">
                                {user.displayName.charAt(0).toUpperCase()}
                              </span>
                            )}
                          </div>
                          <div>
                            <p className="text-primary font-medium">{user.displayName}</p>
                            <p className="text-xs text-muted">{user.email}</p>
                          </div>
                        </div>
                      </td>
                      <td className="px-4 py-3">
                        <span className={`inline-flex items-center gap-1 px-2 py-1 rounded-full text-xs ${
                          user.role === 'admin' 
                            ? 'bg-purple-500/10 text-purple-400' 
                            : 'bg-blue-500/10 text-blue-400'
                        }`}>
                          {user.role === 'admin' && <Crown className="w-3 h-3" />}
                          {user.role === 'admin' ? 'Админ' : 'Пользователь'}
                        </span>
                      </td>
                      <td className="px-4 py-3">
                        <span className={`px-2 py-1 rounded-full text-xs ${
                          user.tier === 'business' 
                            ? 'bg-yellow-500/10 text-yellow-400'
                            : user.tier === 'pro'
                            ? 'bg-green-500/10 text-green-400'
                            : 'bg-gray-500/10 text-gray-400'
                        }`}>
                          {user.tier.toUpperCase()}
                        </span>
                      </td>
                      <td className="px-4 py-3">
                        <span className={`inline-flex items-center gap-1 px-2 py-1 rounded-full text-xs ${
                          user.isActive 
                            ? 'bg-green-500/10 text-green-400' 
                            : 'bg-red-500/10 text-red-400'
                        }`}>
                          {user.isActive ? <UserCheck className="w-3 h-3" /> : <UserX className="w-3 h-3" />}
                          {user.isActive ? 'Активен' : 'Неактивен'}
                        </span>
                      </td>
                      <td className="px-4 py-3 text-sm text-muted">
                        {new Date(user.createdAt).toLocaleDateString('ru-RU')}
                      </td>
                      <td className="px-4 py-3">
                        <div className="relative">
                          <button
                            onClick={() => setActiveMenu(activeMenu === user.id ? null : user.id)}
                            className="p-1 hover:bg-base rounded"
                          >
                            <MoreVertical className="w-4 h-4 text-muted" />
                          </button>
                          {activeMenu === user.id && (
                            <div className="absolute right-0 top-full mt-1 bg-surface border border-border/50 rounded-lg shadow-lg z-10 min-w-[150px]">
                              <button
                                onClick={() => {
                                  setModalUser(user);
                                  setActiveMenu(null);
                                }}
                                className="w-full flex items-center gap-2 px-3 py-2 text-sm text-secondary hover:bg-base"
                              >
                                <Edit className="w-4 h-4" />
                                Редактировать
                              </button>
                              <button
                                onClick={() => {
                                  handleToggleActive(user);
                                  setActiveMenu(null);
                                }}
                                className="w-full flex items-center gap-2 px-3 py-2 text-sm text-secondary hover:bg-base"
                              >
                                {user.isActive ? <UserX className="w-4 h-4" /> : <UserCheck className="w-4 h-4" />}
                                {user.isActive ? 'Деактивировать' : 'Активировать'}
                              </button>
                              <button
                                onClick={() => {
                                  handleDelete(user.id);
                                  setActiveMenu(null);
                                }}
                                className="w-full flex items-center gap-2 px-3 py-2 text-sm text-red-400 hover:bg-base"
                              >
                                <Trash2 className="w-4 h-4" />
                                Удалить
                              </button>
                            </div>
                          )}
                        </div>
                      </td>
                    </tr>
                  ))}
                </tbody>
              </table>
            </div>

            {totalPages > 1 && (
              <div className="flex items-center justify-between px-4 py-3 border-t border-border/30">
                <p className="text-sm text-muted">
                  Показано {users.length} из {total}
                </p>
                <div className="flex gap-2">
                  <button
                    onClick={() => setPage(Math.max(1, page - 1))}
                    disabled={page === 1}
                    className="px-3 py-1 border border-border/50 rounded text-sm disabled:opacity-50"
                  >
                    Назад
                  </button>
                  <span className="px-3 py-1 text-sm text-muted">
                    {page} / {totalPages}
                  </span>
                  <button
                    onClick={() => setPage(Math.min(totalPages, page + 1))}
                    disabled={page === totalPages}
                    className="px-3 py-1 border border-border/50 rounded text-sm disabled:opacity-50"
                  >
                    Вперёд
                  </button>
                </div>
              </div>
            )}
          </>
        )}
      </div>

      {modalUser !== undefined && (
        <UserModal
          user={modalUser || undefined}
          onClose={() => setModalUser(undefined)}
          onSave={handleSave}
        />
      )}
    </div>
  );
}