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

using System;

using Internal.Runtime.Augments;

namespace Internal.Runtime.TypeLoader
{
    public partial struct ExternalReferencesTable
    {
        private unsafe bool Initialize(NativeFormatModuleInfo module, ReflectionMapBlob blobId)
        {
            byte* pBlob;
            uint cbBlob;
            if (!module.TryFindBlob(blobId, out pBlob, out cbBlob))
            {
                _elements = IntPtr.Zero;
                _elementsCount = 0;
                return false;
            }

            _elements = (IntPtr)pBlob;
            _elementsCount = (uint)(cbBlob / sizeof(uint));

            return true;
        }

        /// <summary>
        /// Initialize ExternalReferencesTable using the NativeReferences metadata blob on a given module.
        /// </summary>
        /// <param name="module">Module handle is used to locate the NativeReferences blob</param>
        /// <returns>true when the NativeReferences blob was found in the given module, false when not</returns>
        public bool InitializeNativeReferences(NativeFormatModuleInfo module)
        {
            return Initialize(module, ReflectionMapBlob.NativeReferences);
        }

        /// <summary>
        /// Initialize ExternalReferencesTable using the NativeStatics metadata blob on a given module.
        /// </summary>
        /// <param name="module">Module handle is used to locate the NativeStatics blob</param>
        /// <returns>true when the NativeStatics blob was found in the given module, false when not</returns>
        public bool InitializeNativeStatics(NativeFormatModuleInfo module)
        {
            return Initialize(module, ReflectionMapBlob.NativeStatics);
        }

        /// <summary>
        /// Initialize ExternalReferencesTable using the CommonFixupsTable metadata blob on a given module.
        /// </summary>
        /// <param name="module">Module handle is used to locate the CommonFixupsTable blob</param>
        /// <returns>true when the CommonFixupsTable blob was found in the given module, false when not</returns>
        public bool InitializeCommonFixupsTable(NativeFormatModuleInfo module)
        {
            return Initialize(module, ReflectionMapBlob.CommonFixupsTable);
        }
    }
}