Type CreateDelegateType(MethodInfo delegateMethod)
{
var args = delegateMethod.GetParameters();
TypeBuilder tb = NetHelpers.DefineGlobalType("$DelegateHelper");
FieldBuilder meth = tb.DefineField("meth", typeof(ILuaValue), FieldAttributes.Private);
FieldBuilder E = tb.DefineField("E", typeof(ILuaEnvironment), FieldAttributes.Private);
MethodBuilder mb = NetHelpers.CloneMethod(tb, "Do", delegateMethod);
ILGenerator gen = mb.GetILGenerator();
// loc = new object[{args.Length}];
LocalBuilder loc = gen.CreateArray(typeof(object), args.Length);
for (int i = 0; i < args.Length; i++)
{
// loc[i] = arg_{i+1};
gen.Emit(OpCodes.Ldloc, loc);
gen.Emit(OpCodes.Ldc_I4, i);
gen.Emit(OpCodes.Ldarg, i + 1);
if (args[i].ParameterType.IsValueType)
{
gen.Emit(OpCodes.Box, args[i].ParameterType);
}
gen.Emit(OpCodes.Stelem, typeof(object));
}
// ILuaMultiValue methodArgs = E.Runtime.CreateMultiValueFromObj(loc);
LocalBuilder methodArgs = gen.DeclareLocal(typeof(ILuaMultiValue));
gen.Emit(OpCodes.Ldfld, E);
gen.Emit(OpCodes.Callvirt, typeof(ILuaEnvironment).GetProperty(nameof(ILuaEnvironment.Runtime)).GetGetMethod());
gen.Emit(OpCodes.Ldloc, loc);
gen.Emit(OpCodes.Callvirt, typeof(ILuaRuntime).GetMethod(nameof(ILuaRuntime.CreateMultiValueFromObj)));
gen.Emit(OpCodes.Stloc, methodArgs);
// ret = this.meth.Invoke(LuaNil.Nil, false, -1, methodArgs)
LocalBuilder ret = gen.DeclareLocal(typeof(ILuaMultiValue));
gen.Emit(OpCodes.Ldarg_0);
gen.Emit(OpCodes.Ldfld, meth);
gen.Emit(OpCodes.Ldnull);
gen.Emit(OpCodes.Ldfld, typeof(LuaNil).GetField(nameof(LuaNil.Nil), BindingFlags.Static | BindingFlags.Public));
gen.Emit(OpCodes.Ldc_I4_0);
gen.Emit(OpCodes.Ldc_I4_M1);
gen.Emit(OpCodes.Ldloc, methodArgs);
gen.Emit(OpCodes.Callvirt, typeof(ILuaValue).GetMethod(nameof(ILuaValue.Invoke)));
gen.Emit(OpCodes.Stloc, ret);
// Store any by-ref parameters in the arguments
for (int i = 0; i < args.Length; i++)
{
if (args[i].IsOut)
{
// arg_{i+1} = methodArgs[{i}].As<T>();
gen.Emit(OpCodes.Ldloc, methodArgs);
gen.Emit(OpCodes.Ldc_I4, i);
gen.Emit(OpCodes.Callvirt, typeof(ILuaMultiValue).GetMethod("get_Item"));
gen.Emit(OpCodes.Callvirt, typeof(ILuaValue).GetMethod(nameof(ILuaValue.As))
.MakeGenericMethod(args[i].ParameterType));
gen.Emit(OpCodes.Starg, i + 1);
}
}
// return ret.As<{info.Return}>();
if (delegateMethod.ReturnType != null && delegateMethod.ReturnType != typeof(void))
{
gen.Emit(OpCodes.Ldloc, ret);
gen.Emit(OpCodes.Callvirt, typeof(ILuaValue).GetMethod(nameof(ILuaValue.As))
.MakeGenericMethod(delegateMethod.ReturnType));
}
gen.Emit(OpCodes.Ret);
//// public <>_type_(ILuaEnvironment E, ILuaValue method)
ConstructorBuilder cb = tb.DefineConstructor(MethodAttributes.Public, CallingConventions.Standard,
new[] { typeof(ILuaEnvironment), typeof(ILuaValue) });
gen = cb.GetILGenerator();
// base();
gen.Emit(OpCodes.Ldarg_0);
gen.Emit(OpCodes.Call, typeof(object).GetConstructor(new Type[0]));
// this.E = E;
gen.Emit(OpCodes.Ldarg_0);
gen.Emit(OpCodes.Ldarg_1);
gen.Emit(OpCodes.Stfld, E);
// this.meth = method;
gen.Emit(OpCodes.Ldarg_0);
gen.Emit(OpCodes.Ldarg_2);
gen.Emit(OpCodes.Stfld, meth);
gen.Emit(OpCodes.Ret);
return(tb.CreateType());
}
