CecilGenericSerializerFactory.cs

// Copyright (c) .NET Foundation and Contributors (https://dotnetfoundation.org/ & https://stride3d.net) and Silicon Studio Corp. (https://www.siliconstudio.co.jp)
// Distributed under the MIT license. See the LICENSE.md file in the project root for more information.

using Mono.Cecil;

namespace Stride.Core.AssemblyProcessor;

/// <summary>
/// Gives the specified serializer type constructed with generic arguments of the serialized type.
/// As an example, this instance with <see cref="ListSerializer{}"/> will give <see cref="ListSerializer{int}"/> from <see cref="int"/>.
/// </summary>
public class CecilGenericSerializerFactory : ICecilSerializerFactory
{
    private readonly Type genericSerializableType;
    private readonly bool checkInterfaces;

    protected Func<TypeReference, TypeReference> CreateSerializer { get; set; }

    private CecilGenericSerializerFactory(Type genericSerializableType, Func<TypeReference, TypeReference> createSerializer)
    {
        this.genericSerializableType = genericSerializableType;
        CreateSerializer = createSerializer;
        checkInterfaces = genericSerializableType.IsInterface;
    }

    public CecilGenericSerializerFactory(Type genericSerializableType, TypeReference genericSerializerType)
        : this(genericSerializableType, type => genericSerializerType.MakeGenericType([.. ((GenericInstanceType)type).GenericArguments]))
    {
        if (genericSerializerType == null)
            throw new ArgumentNullException(nameof(genericSerializerType));
        if (genericSerializableType == null)
            throw new ArgumentNullException(nameof(genericSerializableType));
    }

    #region IDataSerializerFactory Members

    public virtual TypeReference? GetSerializer(TypeReference objectType)
    {
        // Check if objectType matches genericSerializableType.
        // Note: Not perfectly valid but hopefully it should be fast enough.
        if (objectType.IsGenericInstance && checkInterfaces)
        {
            if (objectType.GetElementType().Resolve().Interfaces.Any(x => x.InterfaceType.IsGenericInstance && x.InterfaceType.GetElementType().FullName == genericSerializableType.FullName))
                return CreateSerializer(objectType);
        }
        if (objectType.IsGenericInstance && objectType.GetElementType().FullName == genericSerializableType.FullName)
            return CreateSerializer(objectType);

        return null;
    }

    #endregion
}