import { useState, useEffect } from 'react';
import { useRouter } from 'next/router';
import Link from 'next/link';
import { Mail, Lock, AlertCircle } from 'lucide-react';
import authService from '../services/auth';

export default function LoginPage() {
  const router = useRouter();
  const [formData, setFormData] = useState({
    username: '',
    password: ''
  });
  const [loading, setLoading] = useState(false);
  const [error, setError] = useState('');
  const [redirectTo, setRedirectTo] = useState<string | null>(null);

  // Проверяем, есть ли параметр redirect в URL
  useEffect(() => {
    if (router.query.redirect) {
      setRedirectTo(router.query.redirect as string);
    }
    
    // Если пользователь уже авторизован, перенаправляем его
    if (authService.isAuthenticated()) {
      router.push(redirectTo || '/');
    }
  }, [router.query.redirect, redirectTo, router]);

  const handleChange = (e) => {
    const { name, value } = e.target;
    setFormData(prev => ({
      ...prev,
      [name]: value
    }));
  };

  const handleSubmit = async (e) => {
    e.preventDefault();
    setLoading(true);
    setError('');

    try {
      await authService.login(formData);
      
      // Перенаправляем пользователя после успешного входа
      router.push(redirectTo || '/');
    } catch (err) {
      console.error('Ошибка при входе:', err);
      setError('Неверный email или пароль. Пожалуйста, проверьте введенные данные.');
    } finally {
      setLoading(false);
    }
  };

  return (
    <div className="min-h-screen bg-gray-50 flex flex-col justify-center py-12 sm:px-6 lg:px-8">
      <div className="sm:mx-auto sm:w-full sm:max-w-md">
        <h2 className="mt-6 text-center text-3xl font-extrabold text-gray-900">
          Вход в аккаунт
        </h2>
        <p className="mt-2 text-center text-sm text-gray-600">
          Или{' '}
          <Link href="/register" className="font-medium text-indigo-600 hover:text-indigo-500">
            зарегистрируйтесь, если у вас еще нет аккаунта
          </Link>
        </p>
      </div>

      <div className="mt-8 sm:mx-auto sm:w-full sm:max-w-md">
        <div className="bg-white py-8 px-4 shadow sm:rounded-lg sm:px-10">
          {error && (
            <div className="mb-4 bg-red-50 border-l-4 border-red-500 p-4">
              <div className="flex">
                <div className="flex-shrink-0">
                  <AlertCircle className="h-5 w-5 text-red-500" />
                </div>
                <div className="ml-3">
                  <p className="text-sm text-red-700">{error}</p>
                </div>
              </div>
            </div>
          )}

          <form className="space-y-6" onSubmit={handleSubmit}>
            <div>
              <label htmlFor="username" className="block text-sm font-medium text-gray-700">
                Имя пользователя или Email
              </label>
              <div className="mt-1 relative rounded-md shadow-sm">
                <div className="absolute inset-y-0 left-0 pl-3 flex items-center pointer-events-none">
                  <Mail className="h-5 w-5 text-gray-400" />
                </div>
                <input
                  id="username"
                  name="username"
                  type="text"
                  autoComplete="username"
                  required
                  value={formData.username}
                  onChange={handleChange}
                  className="block w-full pl-10 pr-3 py-2 border border-gray-300 rounded-md shadow-sm placeholder-gray-400 focus:outline-none focus:ring-indigo-500 focus:border-indigo-500 sm:text-sm"
                  placeholder="username или example@example.com"
                />
              </div>
            </div>

            <div>
              <label htmlFor="password" className="block text-sm font-medium text-gray-700">
                Пароль
              </label>
              <div className="mt-1 relative rounded-md shadow-sm">
                <div className="absolute inset-y-0 left-0 pl-3 flex items-center pointer-events-none">
                  <Lock className="h-5 w-5 text-gray-400" />
                </div>
                <input
                  id="password"
                  name="password"
                  type="password"
                  autoComplete="current-password"
                  required
                  value={formData.password}
                  onChange={handleChange}
                  className="block w-full pl-10 pr-3 py-2 border border-gray-300 rounded-md shadow-sm placeholder-gray-400 focus:outline-none focus:ring-indigo-500 focus:border-indigo-500 sm:text-sm"
                  placeholder="••••••••"
                />
              </div>
            </div>

            <div className="flex items-center justify-between">
              <div className="flex items-center">
                <input
                  id="remember_me"
                  name="remember_me"
                  type="checkbox"
                  className="h-4 w-4 text-indigo-600 focus:ring-indigo-500 border-gray-300 rounded"
                />
                <label htmlFor="remember_me" className="ml-2 block text-sm text-gray-900">
                  Запомнить меня
                </label>
              </div>

              <div className="text-sm">
                <Link href="/forgot-password" className="font-medium text-indigo-600 hover:text-indigo-500">
                  Забыли пароль?
                </Link>
              </div>
            </div>

            <div>
              <button
                type="submit"
                disabled={loading}
                className="w-full flex justify-center py-2 px-4 border border-transparent rounded-md shadow-sm text-sm font-medium text-white bg-indigo-600 hover:bg-indigo-700 focus:outline-none focus:ring-2 focus:ring-offset-2 focus:ring-indigo-500 disabled:opacity-50 disabled:cursor-not-allowed"
              >
                {loading ? 'Вход...' : 'Войти'}
              </button>
            </div>
          </form>

          <div className="mt-6">
            <div className="relative">
              <div className="absolute inset-0 flex items-center">
                <div className="w-full border-t border-gray-300"></div>
              </div>
              <div className="relative flex justify-center text-sm">
                <span className="px-2 bg-white text-gray-500">Или войдите через</span>
              </div>
            </div>

            <div className="mt-6 grid grid-cols-2 gap-3">
              <div>
                <a
                  href="#"
                  className="w-full inline-flex justify-center py-2 px-4 border border-gray-300 rounded-md shadow-sm bg-white text-sm font-medium text-gray-500 hover:bg-gray-50"
                >
                  <span className="sr-only">Войти через Google</span>
                  <svg className="w-5 h-5" fill="currentColor" viewBox="0 0 24 24" aria-hidden="true">
                    <path d="M12.48 10.92v3.28h7.84c-.24 1.84-.853 3.187-1.787 4.133-1.147 1.147-2.933 2.4-6.053 2.4-4.827 0-8.6-3.893-8.6-8.72s3.773-8.72 8.6-8.72c2.6 0 4.507 1.027 5.907 2.347l2.307-2.307C18.747 1.44 16.133 0 12.48 0 5.867 0 .307 5.387.307 12s5.56 12 12.173 12c3.573 0 6.267-1.173 8.373-3.36 2.16-2.16 2.84-5.213 2.84-7.667 0-.76-.053-1.467-.173-2.053H12.48z" />
                  </svg>
                </a>
              </div>

              <div>
                <a
                  href="#"
                  className="w-full inline-flex justify-center py-2 px-4 border border-gray-300 rounded-md shadow-sm bg-white text-sm font-medium text-gray-500 hover:bg-gray-50"
                >
                  <span className="sr-only">Войти через Facebook</span>
                  <svg className="w-5 h-5" fill="currentColor" viewBox="0 0 24 24" aria-hidden="true">
                    <path fillRule="evenodd" d="M22 12c0-5.523-4.477-10-10-10S2 6.477 2 12c0 4.991 3.657 9.128 8.438 9.878v-6.987h-2.54V12h2.54V9.797c0-2.506 1.492-3.89 3.777-3.89 1.094 0 2.238.195 2.238.195v2.46h-1.26c-1.243 0-1.63.771-1.63 1.562V12h2.773l-.443 2.89h-2.33v6.988C18.343 21.128 22 16.991 22 12z" clipRule="evenodd" />
                  </svg>
                </a>
              </div>
            </div>
          </div>
        </div>
      </div>
    </div>
  );
}