// 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.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
 
namespace Microsoft.AspNetCore.Mvc.ModelBinding.Binders;
 
/// <summary>
/// An <see cref="IModelBinderProvider"/> for arrays.
/// </summary>
public class ArrayModelBinderProvider : IModelBinderProvider
{
    /// <inheritdoc />
    public IModelBinder? GetBinder(ModelBinderProviderContext context)
    {
        ArgumentNullException.ThrowIfNull(context);
 
        if (context.Metadata.ModelType.IsArray)
        {
            var elementType = context.Metadata.ElementMetadata!.ModelType;
            var binderType = typeof(ArrayModelBinder<>).MakeGenericType(elementType);
            var elementBinder = context.CreateBinder(context.Metadata.ElementMetadata);
 
            var loggerFactory = context.Services.GetRequiredService<ILoggerFactory>();
            var mvcOptions = context.Services.GetRequiredService<IOptions<MvcOptions>>().Value;
            return (IModelBinder)Activator.CreateInstance(
                binderType,
                elementBinder,
                loggerFactory,
                true /* allowValidatingTopLevelNodes */,
                mvcOptions)!;
        }
 
        return null;
    }
}