/* ****************************************************************************
 *
 * Copyright (c) Microsoft Corporation. 
 *
 * This source code is subject to terms and conditions of the Apache License, Version 2.0. A 
 * copy of the license can be found in the License.html file at the root of this distribution. If 
 * you cannot locate the  Apache License, Version 2.0, please send an email to 
 * dlr@microsoft.com. By using this source code in any fashion, you are agreeing to be bound 
 * by the terms of the Apache License, Version 2.0.
 *
 * You must not remove this notice, or any other, from this software.
 *
 *
 * ***************************************************************************/

using System;
using System.Dynamic.Utils;
using System.Reflection;
using System.Reflection.Emit;

#if !FEATURE_CORE_DLR
namespace Microsoft.Scripting.Ast.Compiler {
#else
namespace System.Linq.Expressions.Compiler {
#endif
    internal static partial class DelegateHelpers {
        private const MethodAttributes CtorAttributes = MethodAttributes.RTSpecialName | MethodAttributes.HideBySig | MethodAttributes.Public;
        private const MethodImplAttributes ImplAttributes = MethodImplAttributes.Runtime | MethodImplAttributes.Managed;
        private const MethodAttributes InvokeAttributes = MethodAttributes.Public | MethodAttributes.HideBySig | MethodAttributes.NewSlot | MethodAttributes.Virtual;
        private static readonly Type[] _DelegateCtorSignature = new Type[] { typeof(object), typeof(IntPtr) };

        private static Type MakeNewCustomDelegate(Type[] types) {
#if FEATURE_REFEMIT
            Type returnType = types[types.Length - 1];
            Type[] parameters = types.RemoveLast();

            TypeBuilder builder = AssemblyGen.DefineDelegateType("Delegate" + types.Length);
            builder.DefineConstructor(CtorAttributes, CallingConventions.Standard, _DelegateCtorSignature).SetImplementationFlags(ImplAttributes);
            builder.DefineMethod("Invoke", InvokeAttributes, returnType, parameters).SetImplementationFlags(ImplAttributes);
            return builder.CreateType();
#else
            throw new NotSupportedException("Method signature not supported on this platform");
#endif
        }
    }
}