// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
using System.Reflection;
using Microsoft.Extensions.Internal;
 
namespace Microsoft.AspNetCore.Mvc.RazorPages.Infrastructure;
 
internal sealed class DefaultPageModelFactoryProvider : IPageModelFactoryProvider
{
    private static readonly Func<PropertyInfo, PropertyActivator<PageContext>> _createActivateInfo =
        CreateActivateInfo;
    private readonly IPageModelActivatorProvider _modelActivator;
 
    public DefaultPageModelFactoryProvider(IPageModelActivatorProvider modelActivator)
    {
        _modelActivator = modelActivator;
    }
 
    public Func<PageContext, object>? CreateModelFactory(CompiledPageActionDescriptor descriptor)
    {
        ArgumentNullException.ThrowIfNull(descriptor);
 
        if (descriptor.ModelTypeInfo == null)
        {
            return null;
        }
 
        var modelActivator = _modelActivator.CreateActivator(descriptor);
        var propertyActivator = PropertyActivator<PageContext>.GetPropertiesToActivate(
                descriptor.ModelTypeInfo.AsType(),
                typeof(PageContextAttribute),
                _createActivateInfo,
                includeNonPublic: false);
 
        return pageContext =>
        {
            var model = modelActivator(pageContext);
            for (var i = 0; i < propertyActivator.Length; i++)
            {
                propertyActivator[i].Activate(model, pageContext);
            }
 
            return model;
        };
    }
 
    public Action<PageContext, object>? CreateModelDisposer(CompiledPageActionDescriptor descriptor)
    {
        ArgumentNullException.ThrowIfNull(descriptor);
 
        if (descriptor.ModelTypeInfo == null)
        {
            return null;
        }
 
        return _modelActivator.CreateReleaser(descriptor);
    }
 
    public Func<PageContext, object, ValueTask>? CreateAsyncModelDisposer(CompiledPageActionDescriptor descriptor)
    {
        ArgumentNullException.ThrowIfNull(descriptor);
 
        if (descriptor.ModelTypeInfo == null)
        {
            return null;
        }
 
        return _modelActivator.CreateAsyncReleaser(descriptor);
    }
 
    private static PropertyActivator<PageContext> CreateActivateInfo(PropertyInfo property) =>
        new PropertyActivator<PageContext>(property, pageContext => pageContext);
}