// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using Microsoft.AspNetCore.Http.Metadata;
using Microsoft.AspNetCore.Mvc.Filters;
using Microsoft.Extensions.DependencyInjection;
 
namespace Microsoft.AspNetCore.Mvc;
 
/// <summary>
/// Sets the request body size limit to the specified size.
/// </summary>
[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = false, Inherited = true)]
public class RequestSizeLimitAttribute : Attribute, IFilterFactory, IOrderedFilter, IRequestSizeLimitMetadata
{
    private readonly long _bytes;
 
    /// <summary>
    /// Creates a new instance of <see cref="RequestSizeLimitAttribute"/>.
    /// </summary>
    /// <param name="bytes">The request body size limit.</param>
    public RequestSizeLimitAttribute(long bytes)
    {
        _bytes = bytes;
    }
 
    /// <summary>
    /// Gets the order value for determining the order of execution of filters. Filters execute in
    /// ascending numeric value of the <see cref="Order"/> property.
    /// </summary>
    /// <remarks>
    /// <para>
    /// Filters are executed in an ordering determined by an ascending sort of the <see cref="Order"/> property.
    /// </para>
    /// <para>
    /// The default Order for this attribute is 900 because it must run before ValidateAntiForgeryTokenAttribute and
    /// after any filter which does authentication or login in order to allow them to behave as expected (ie Unauthenticated or Redirect instead of 400).
    /// </para>
    /// <para>
    /// Look at <see cref="IOrderedFilter.Order"/> for more detailed info.
    /// </para>
    /// </remarks>
    public int Order { get; set; } = 900;
 
    /// <inheritdoc />
    public bool IsReusable => true;
 
    /// <inheritdoc />
    public IFilterMetadata CreateInstance(IServiceProvider serviceProvider)
    {
        var filter = serviceProvider.GetRequiredService<RequestSizeLimitFilter>();
        filter.Bytes = _bytes;
        return filter;
    }
 
    /// <inheritdoc />
    long? IRequestSizeLimitMetadata.MaxRequestBodySize => _bytes;
}