'use client';

import { useState, useEffect, useRef } from 'react';
import { useForm } from 'react-hook-form';
import { zodResolver } from '@hookform/resolvers/zod';
import { z } from 'zod';
import api from '@/lib/api';
import { useUserStore } from '@/stores/userStore';

const profileSchema = z.object({
  firstName: z.string().optional(),
  lastName: z.string().optional(),
  email: z.string().email('Invalid email format').optional().or(z.literal('')),
  phone: z.string().regex(/^1[3-9]\d{9}$/, 'Invalid phone format').optional().or(z.literal('')),
});

type ProfileFormData = z.infer<typeof profileSchema>;

export default function ProfilePage() {
  const { user, setUser } = useUserStore();
  const [loading, setLoading] = useState(false);
  const [message, setMessage] = useState<string | null>(null);
  const [error, setError] = useState<string | null>(null);
  const fileInputRef = useRef<HTMLInputElement>(null);

  const {
    register,
    handleSubmit,
    reset,
    formState: { errors },
  } = useForm<ProfileFormData>({
    resolver: zodResolver(profileSchema),
  });

  useEffect(() => {
    if (user) {
      reset({
        firstName: user.firstName || '',
        lastName: user.lastName || '',
        email: user.email || '',
        phone: user.phone || '',
      });
    }
  }, [user, reset]);

  const onSubmit = async (data: ProfileFormData) => {
    try {
      setError(null);
      setMessage(null);
      setLoading(true);
      const response = await api.put('/users/me', {
        firstName: data.firstName || undefined,
        lastName: data.lastName || undefined,
        email: data.email || undefined,
        phone: data.phone || undefined,
      });

      const updatedUser = response.data.data;
      setUser({
        ...user,
        ...updatedUser,
      });
      setMessage('Profile updated successfully');
    } catch (err) {
      const error = err as { response?: { data?: { message?: string } } };
      setError(error.response?.data?.message || 'Failed to update profile');
    } finally {
      setLoading(false);
    }
  };

  const handleAvatarUpload = async (e: React.ChangeEvent<HTMLInputElement>) => {
    const file = e.target.files?.[0];
    if (!file) return;

    if (!file.type.startsWith('image/')) {
      setError('Please upload an image file');
      return;
    }

    if (file.size > 5 * 1024 * 1024) {
      setError('Image size must be less than 5MB');
      return;
    }

    try {
      setError(null);
      setLoading(true);
      const formData = new FormData();
      formData.append('avatar', file);

      const response = await api.post('/users/me/avatar', formData, {
        headers: {
          'Content-Type': 'multipart/form-data',
        },
      });

      const updatedUser = response.data.data;
      setUser({
        ...user,
        avatar: updatedUser.avatar,
      });
      setMessage('Avatar updated successfully');
    } catch (err) {
      const error = err as { response?: { data?: { message?: string } } };
      setError(error.response?.data?.message || 'Failed to upload avatar');
    } finally {
      setLoading(false);
    }
  };

  const handleLogout = () => {
    localStorage.removeItem('token');
    setUser(null);
    window.location.href = '/auth/login';
  };

  if (!user) {
    return <div className="p-6">Loading...</div>;
  }

  return (
    <div className="max-w-2xl mx-auto p-6 space-y-6">
      <h1 className="text-2xl font-bold">Profile Settings</h1>

      <div className="space-y-4">
        <div className="flex items-center space-x-4">
          <div className="w-20 h-20 rounded-full bg-gray-200 flex items-center justify-center overflow-hidden">
            {user.avatar ? (
              <img src={user.avatar} alt="Avatar" className="w-full h-full object-cover" />
            ) : (
              <span className="text-2xl font-bold text-gray-500">
                {user.firstName?.[0] || user.username?.[0] || 'U'}
              </span>
            )}
          </div>
          <div>
            <button
              type="button"
              onClick={() => fileInputRef.current?.click()}
              className="px-4 py-2 text-sm border rounded-md hover:bg-gray-50"
              disabled={loading}
            >
              Change Avatar
            </button>
            <input
              ref={fileInputRef}
              type="file"
              accept="image/*"
              onChange={handleAvatarUpload}
              className="hidden"
            />
            <p className="text-xs text-gray-500 mt-1">JPG, PNG, GIF or WebP (max 5MB)</p>
          </div>
        </div>

        <form onSubmit={handleSubmit(onSubmit)} className="space-y-4">
          <div className="grid grid-cols-2 gap-4">
            <div className="space-y-2">
              <label className="text-sm font-medium">First Name</label>
              <input
                type="text"
                {...register('firstName')}
                className="w-full px-3 py-2 border rounded-md"
                placeholder="John"
              />
              {errors.firstName && (
                <p className="text-sm text-red-500">{errors.firstName.message}</p>
              )}
            </div>

            <div className="space-y-2">
              <label className="text-sm font-medium">Last Name</label>
              <input
                type="text"
                {...register('lastName')}
                className="w-full px-3 py-2 border rounded-md"
                placeholder="Doe"
              />
              {errors.lastName && (
                <p className="text-sm text-red-500">{errors.lastName.message}</p>
              )}
            </div>
          </div>

          <div className="space-y-2">
            <label className="text-sm font-medium">Username</label>
            <input
              type="text"
              value={user.username || ''}
              disabled
              className="w-full px-3 py-2 border rounded-md bg-gray-50"
            />
          </div>

          <div className="space-y-2">
            <label className="text-sm font-medium">Email</label>
            <input
              type="email"
              {...register('email')}
              className="w-full px-3 py-2 border rounded-md"
              placeholder="your@email.com"
            />
            {errors.email && (
              <p className="text-sm text-red-500">{errors.email.message}</p>
            )}
          </div>

          <div className="space-y-2">
            <label className="text-sm font-medium">Phone</label>
            <input
              type="tel"
              {...register('phone')}
              className="w-full px-3 py-2 border rounded-md"
              placeholder="13800138000"
            />
            {errors.phone && (
              <p className="text-sm text-red-500">{errors.phone.message}</p>
            )}
          </div>

          {message && (
            <div className="p-3 bg-green-50 border border-green-200 rounded-md text-green-600 text-sm">
              {message}
            </div>
          )}

          {error && (
            <div className="p-3 bg-red-50 border border-red-200 rounded-md text-red-600 text-sm">
              {error}
            </div>
          )}

          <div className="flex space-x-4">
            <button
              type="submit"
              disabled={loading}
              className="flex-1 py-2 px-4 bg-primary text-primary-foreground rounded-md hover:bg-primary/90 disabled:opacity-50 disabled:cursor-not-allowed"
            >
              {loading ? 'Saving...' : 'Save Changes'}
            </button>
            <button
              type="button"
              onClick={handleLogout}
              className="py-2 px-4 border border-red-300 text-red-600 rounded-md hover:bg-red-50"
            >
              Logout
            </button>
          </div>
        </form>
      </div>
    </div>
  );
}