// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
#nullable enable
 
using Microsoft.AspNetCore.Mvc.Core;
using Microsoft.Extensions.DependencyInjection;
 
namespace Microsoft.AspNetCore.Mvc.ModelBinding.Binders;
 
/// <summary>
/// An <see cref="IModelBinder"/> for models which specify an <see cref="IModelBinder"/> using
/// <see cref="BindingInfo.BinderType"/>.
/// </summary>
public class BinderTypeModelBinder : IModelBinder
{
    private readonly ObjectFactory _factory;
 
    /// <summary>
    /// Creates a new <see cref="BinderTypeModelBinder"/>.
    /// </summary>
    /// <param name="binderType">The <see cref="Type"/> of the <see cref="IModelBinder"/>.</param>
    public BinderTypeModelBinder(Type binderType)
    {
        ArgumentNullException.ThrowIfNull(binderType);
 
        if (!typeof(IModelBinder).IsAssignableFrom(binderType))
        {
            throw new ArgumentException(
                Resources.FormatBinderType_MustBeIModelBinder(
                    binderType.FullName,
                    typeof(IModelBinder).FullName),
                nameof(binderType));
        }
 
        _factory = ActivatorUtilities.CreateFactory(binderType, Type.EmptyTypes);
    }
 
    /// <inheritdoc />
    public async Task BindModelAsync(ModelBindingContext bindingContext)
    {
        ArgumentNullException.ThrowIfNull(bindingContext);
 
        var requestServices = bindingContext.HttpContext.RequestServices;
        var binder = (IModelBinder)_factory(requestServices, arguments: null);
 
        await binder.BindModelAsync(bindingContext);
    }
}