// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.

using Internal.Metadata.NativeFormat.Writer;

using Cts = Internal.TypeSystem;
using Ecma = System.Reflection.Metadata;

namespace ILCompiler.Metadata
{
    /// <summary>
    /// Controls metadata generation policy. Decides what types and members will get metadata.
    /// </summary>
    /// <remarks>
    /// Thread safety: the implementers are required to be thread safe.
    /// </remarks>
    public interface IMetadataPolicy
    {
        /// <summary>
        /// Returns true if the type should generate <see cref="TypeDefinition"/> metadata. If false,
        /// the type will generate a <see cref="TypeReference"/> if required within the object graph.
        /// </summary>
        /// <param name="typeDef">Uninstantiated type definition to check.</param>
        bool GeneratesMetadata(Cts.MetadataType typeDef);

        /// <summary>
        /// Returns true if the method should generate <see cref="Method"/> metadata. If false,
        /// the method should generate a <see cref="MemberReference"/> when needed.
        /// </summary>
        /// <param name="methodDef">Uninstantiated method definition to check.</param>
        bool GeneratesMetadata(Cts.MethodDesc methodDef);

        /// <summary>
        /// Returns true if the field should generate <see cref="Field"/> metadata. If false,
        /// the field should generate a <see cref="MemberReference"/> when needed.
        /// </summary>
        /// <param name="fieldDef">Uninstantiated field definition to check.</param>
        bool GeneratesMetadata(Cts.FieldDesc fieldDef);

        /// <summary>
        /// Returns true if the custom attribute should generate <see cref="CustomAttribute"/> metadata.
        /// If false, the custom attribute is not generated.
        /// </summary>
        bool GeneratesMetadata(Cts.Ecma.EcmaModule module, Ecma.CustomAttributeHandle customAttribute);

        /// <summary>
        /// Returns true if the parameter should generate <see cref="Parameter"/> metadata.
        /// If false, the parameter is not generated.
        /// </summary>
        bool GeneratesMetadata(Cts.Ecma.EcmaModule module, Ecma.ParameterHandle parameter);

        /// <summary>
        /// Returns true if an exported type entry should generate <see cref="TypeForwarder"/> metadata.
        /// </summary>
        bool GeneratesMetadata(Cts.Ecma.EcmaModule module, Ecma.ExportedTypeHandle exportedType);

        /// <summary>
        /// Returns true if InterfaceImpl should be generated for this type.
        /// </summary>
        bool GeneratesInterfaceImpl(Cts.MetadataType typeDef, Cts.MetadataType interfaceImpl);

        /// <summary>
        /// Returns true if a type should be blocked from generating any metadata.
        /// Blocked interfaces are skipped from interface lists, and custom attributes referring to
        /// blocked types are dropped from metadata.
        /// </summary>
        bool IsBlocked(Cts.MetadataType typeDef);

        bool IsBlocked(Cts.MethodDesc methodDef);
    }
}