// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
 
/*============================================================
**
**
**
**
**
** Eventbuilder is for client to define eevnts for a class
**
**
===========================================================*/
 
using System.Runtime.CompilerServices;
 
namespace System.Reflection.Emit
{
    //
    // A EventBuilder is always associated with a TypeBuilder.  The TypeBuilder.DefineEvent
    // method will return a new EventBuilder to a client.
    //
    internal sealed class RuntimeEventBuilder : EventBuilder
    {
        // Constructs a RuntimeEventBuilder.
        //
        internal RuntimeEventBuilder(
            RuntimeModuleBuilder mod,               // the module containing this EventBuilder
            string name,                            // Event name
            EventAttributes attr,                   // event attribute such as Public, Private, and Protected defined above
            RuntimeTypeBuilder type,                // containing type
            int evToken)
        {
            m_name = name;
            m_module = mod;
            m_attributes = attr;
            m_evToken = evToken;
            m_type = type;
        }
 
        // Return the Token for this event within the TypeBuilder that the
        // event is defined within.
        internal int GetEventToken()
        {
            return m_evToken;
        }
 
        private void SetMethodSemantics(MethodBuilder mdBuilder, MethodSemanticsAttributes semantics)
        {
            ArgumentNullException.ThrowIfNull(mdBuilder);
 
            m_type.ThrowIfCreated();
            RuntimeModuleBuilder module = m_module;
            RuntimeTypeBuilder.DefineMethodSemantics(
                new QCallModule(ref module),
                m_evToken,
                semantics,
                mdBuilder.MetadataToken);
        }
 
        protected override void SetAddOnMethodCore(MethodBuilder mdBuilder)
        {
            SetMethodSemantics(mdBuilder, MethodSemanticsAttributes.AddOn);
        }
 
        protected override void SetRemoveOnMethodCore(MethodBuilder mdBuilder)
        {
            SetMethodSemantics(mdBuilder, MethodSemanticsAttributes.RemoveOn);
        }
 
        protected override void SetRaiseMethodCore(MethodBuilder mdBuilder)
        {
            SetMethodSemantics(mdBuilder, MethodSemanticsAttributes.Fire);
        }
 
        protected override void AddOtherMethodCore(MethodBuilder mdBuilder)
        {
            SetMethodSemantics(mdBuilder, MethodSemanticsAttributes.Other);
        }
 
        // Use this function if client decides to form the custom attribute blob themselves
 
        protected override void SetCustomAttributeCore(ConstructorInfo con, ReadOnlySpan<byte> binaryAttribute)
        {
            m_type.ThrowIfCreated();
 
            RuntimeTypeBuilder.DefineCustomAttribute(
                m_module,
                m_evToken,
                m_module.GetMethodMetadataToken(con),
                binaryAttribute);
        }
 
        private readonly string m_name;         // The name of the event
        private readonly int m_evToken;      // The token of this event
        private readonly RuntimeModuleBuilder m_module;
        private readonly EventAttributes m_attributes;
        private readonly RuntimeTypeBuilder m_type;
    }
}