/*
  Copyright (C) 2002-2013 Jeroen Frijters

  This software is provided 'as-is', without any express or implied
  warranty.  In no event will the authors be held liable for any damages
  arising from the use of this software.

  Permission is granted to anyone to use this software for any purpose,
  including commercial applications, and to alter it and redistribute it
  freely, subject to the following restrictions:

  1. The origin of this software must not be misrepresented; you must not
     claim that you wrote the original software. If you use this software
     in a product, an acknowledgment in the product documentation would be
     appreciated but is not required.
  2. Altered source versions must be plainly marked as such, and must not be
     misrepresented as being the original software.
  3. This notice may not be removed or altered from any source distribution.

  Jeroen Frijters
  jeroen@frijters.net
  
*/
using System;
using System.IO;
using System.Collections.Generic;
#if STUB_GENERATOR
using IKVM.Reflection;
using Type = IKVM.Reflection.Type;
#else
using System.Reflection;
#endif
using IKVM.Attributes;
using IKVM.Internal;

namespace IKVM.StubGen
{
	static class StubGenerator
	{
		internal static void WriteClass(Stream stream, TypeWrapper tw, bool includeNonPublicInterfaces, bool includeNonPublicMembers, bool includeSerialVersionUID, bool includeParameterNames)
		{
			string name = tw.Name.Replace('.', '/');
			string super = null;
			if (tw.IsInterface)
			{
				super = "java/lang/Object";
			}
			else if (tw.BaseTypeWrapper != null)
			{
				super = tw.BaseTypeWrapper.Name.Replace('.', '/');
			}
			ClassFileWriter writer = new ClassFileWriter(tw.Modifiers, name, super, 0, includeParameterNames ? (ushort)52 : (ushort)49);
			foreach (TypeWrapper iface in tw.Interfaces)
			{
				if (iface.IsPublic || includeNonPublicInterfaces)
				{
					writer.AddInterface(iface.Name.Replace('.', '/'));
				}
			}
			InnerClassesAttribute innerClassesAttribute = null;
			if (tw.DeclaringTypeWrapper != null)
			{
				TypeWrapper outer = tw.DeclaringTypeWrapper;
				string innername = name;
				int idx = name.LastIndexOf('$');
				if (idx >= 0)
				{
					innername = innername.Substring(idx + 1);
				}
				innerClassesAttribute = new InnerClassesAttribute(writer);
				innerClassesAttribute.Add(name, outer.Name.Replace('.', '/'), innername, (ushort)tw.ReflectiveModifiers);
			}
			foreach (TypeWrapper inner in tw.InnerClasses)
			{
				if (inner.IsPublic)
				{
					if (innerClassesAttribute == null)
					{
						innerClassesAttribute = new InnerClassesAttribute(writer);
					}
					string namePart = inner.Name;
					namePart = namePart.Substring(namePart.LastIndexOf('$') + 1);
					innerClassesAttribute.Add(inner.Name.Replace('.', '/'), name, namePart, (ushort)inner.ReflectiveModifiers);
				}
			}
			if (innerClassesAttribute != null)
			{
				writer.AddAttribute(innerClassesAttribute);
			}
			string genericTypeSignature = tw.GetGenericSignature();
			if (genericTypeSignature != null)
			{
				writer.AddStringAttribute("Signature", genericTypeSignature);
			}
			AddAnnotations(writer, writer, tw.TypeAsBaseType);
			AddTypeAnnotations(writer, writer, tw, tw.GetRawTypeAnnotations());
			writer.AddStringAttribute("IKVM.NET.Assembly", GetAssemblyName(tw));
			if (tw.TypeAsBaseType.IsDefined(JVM.Import(typeof(ObsoleteAttribute)), false))
			{
				writer.AddAttribute(new DeprecatedAttribute(writer));
			}
			foreach (MethodWrapper mw in tw.GetMethods())
			{
				if (!mw.IsHideFromReflection && (mw.IsPublic || mw.IsProtected || includeNonPublicMembers))
				{
					FieldOrMethod m;
					// HACK javac has a bug in com.sun.tools.javac.code.Types.isSignaturePolymorphic() where it assumes that
					// MethodHandle doesn't have any native methods with an empty argument list
					// (or at least it throws a NPE when it examines the signature of a method without any parameters when it
					// accesses argtypes.tail.tail)
					if (mw.Name == "<init>" || (tw == CoreClasses.java.lang.invoke.MethodHandle.Wrapper && (mw.Modifiers & Modifiers.Native) == 0))
					{
						m = writer.AddMethod(mw.Modifiers, mw.Name, mw.Signature.Replace('.', '/'));
						CodeAttribute code = new CodeAttribute(writer);
						code.MaxLocals = (ushort)(mw.GetParameters().Length * 2 + 1);
						code.MaxStack = 3;
						ushort index1 = writer.AddClass("java/lang/UnsatisfiedLinkError");
						ushort index2 = writer.AddString("ikvmstub generated stubs can only be used on IKVM.NET");
						ushort index3 = writer.AddMethodRef("java/lang/UnsatisfiedLinkError", "<init>", "(Ljava/lang/String;)V");
						code.ByteCode = new byte[] {
						187, (byte)(index1 >> 8), (byte)index1,	// new java/lang/UnsatisfiedLinkError
						89,										// dup
						19,	 (byte)(index2 >> 8), (byte)index2,	// ldc_w "..."
						183, (byte)(index3 >> 8), (byte)index3, // invokespecial java/lang/UnsatisfiedLinkError/init()V
						191										// athrow
					};
						m.AddAttribute(code);
					}
					else
					{
						Modifiers mods = mw.Modifiers;
						if ((mods & Modifiers.Abstract) == 0)
						{
							mods |= Modifiers.Native;
						}
						m = writer.AddMethod(mods, mw.Name, mw.Signature.Replace('.', '/'));
						if (mw.IsOptionalAttributeAnnotationValue)
						{
							m.AddAttribute(new AnnotationDefaultClassFileAttribute(writer, GetAnnotationDefault(writer, mw.ReturnType)));
						}
					}
					MethodBase mb = mw.GetMethod();
					if (mb != null)
					{
						ThrowsAttribute throws = AttributeHelper.GetThrows(mb);
						if (throws == null)
						{
							string[] throwsArray = mw.GetDeclaredExceptions();
							if (throwsArray != null && throwsArray.Length > 0)
							{
								ExceptionsAttribute attrib = new ExceptionsAttribute(writer);
								foreach (string ex in throwsArray)
								{
									attrib.Add(ex.Replace('.', '/'));
								}
								m.AddAttribute(attrib);
							}
						}
						else
						{
							ExceptionsAttribute attrib = new ExceptionsAttribute(writer);
							if (throws.classes != null)
							{
								foreach (string ex in throws.classes)
								{
									attrib.Add(ex.Replace('.', '/'));
								}
							}
							if (throws.types != null)
							{
								foreach (Type ex in throws.types)
								{
									attrib.Add(ClassLoaderWrapper.GetWrapperFromType(ex).Name.Replace('.', '/'));
								}
							}
							m.AddAttribute(attrib);
						}
						if (mb.IsDefined(JVM.Import(typeof(ObsoleteAttribute)), false)
							// HACK the instancehelper methods are marked as Obsolete (to direct people toward the ikvm.extensions methods instead)
							// but in the Java world most of them are not deprecated (and to keep the Japi results clean we need to reflect this)
							&& (!mb.Name.StartsWith("instancehelper_")
								|| mb.DeclaringType.FullName != "java.lang.String"
							// the Java deprecated methods actually have two Obsolete attributes
								|| GetObsoleteCount(mb) == 2))
						{
							m.AddAttribute(new DeprecatedAttribute(writer));
						}
						CustomAttributeData attr = GetAnnotationDefault(mb);
						if (attr != null)
						{
							m.AddAttribute(new AnnotationDefaultClassFileAttribute(writer, GetAnnotationDefault(writer, attr.ConstructorArguments[0])));
						}
						if (includeParameterNames)
						{
							MethodParametersEntry[] mp = tw.GetMethodParameters(mw);
							if (mp == MethodParametersEntry.Malformed)
							{
								m.AddAttribute(new MethodParametersAttribute(writer, null, null));
							}
							else if (mp != null)
							{
								ushort[] names = new ushort[mp.Length];
								ushort[] flags = new ushort[mp.Length];
								for (int i = 0; i < names.Length; i++)
								{
									if (mp[i].name != null)
									{
										names[i] = writer.AddUtf8(mp[i].name);
									}
									flags[i] = mp[i].flags;
								}
								m.AddAttribute(new MethodParametersAttribute(writer, names, flags));
							}
						}
					}
					string sig = tw.GetGenericMethodSignature(mw);
					if (sig != null)
					{
						m.AddAttribute(writer.MakeStringAttribute("Signature", sig));
					}
					AddAnnotations(writer, m, mw.GetMethod());
					AddParameterAnnotations(writer, m, mw.GetMethod());
					AddTypeAnnotations(writer, m, tw, tw.GetMethodRawTypeAnnotations(mw));
				}
			}
			bool hasSerialVersionUID = false;
			foreach (FieldWrapper fw in tw.GetFields())
			{
				if (!fw.IsHideFromReflection)
				{
					bool isSerialVersionUID = includeSerialVersionUID && fw.Name == "serialVersionUID" && fw.FieldTypeWrapper == PrimitiveTypeWrapper.LONG;
					hasSerialVersionUID |= isSerialVersionUID;
					if (fw.IsPublic || fw.IsProtected || isSerialVersionUID || includeNonPublicMembers)
					{
						object constant = null;
						if (fw.GetField() != null && fw.GetField().IsLiteral && (fw.FieldTypeWrapper.IsPrimitive || fw.FieldTypeWrapper == CoreClasses.java.lang.String.Wrapper))
						{
							constant = fw.GetField().GetRawConstantValue();
							if (fw.GetField().FieldType.IsEnum)
							{
								constant = EnumHelper.GetPrimitiveValue(EnumHelper.GetUnderlyingType(fw.GetField().FieldType), constant);
							}
						}
						FieldOrMethod f = writer.AddField(fw.Modifiers, fw.Name, fw.Signature.Replace('.', '/'), constant);
						string sig = tw.GetGenericFieldSignature(fw);
						if (sig != null)
						{
							f.AddAttribute(writer.MakeStringAttribute("Signature", sig));
						}
						if (fw.GetField() != null && fw.GetField().IsDefined(JVM.Import(typeof(ObsoleteAttribute)), false))
						{
							f.AddAttribute(new DeprecatedAttribute(writer));
						}
						AddAnnotations(writer, f, fw.GetField());
						AddTypeAnnotations(writer, f, tw, tw.GetFieldRawTypeAnnotations(fw));
					}
				}
			}
			if (includeSerialVersionUID && !hasSerialVersionUID && IsSerializable(tw))
			{
				// class is serializable but doesn't have an explicit serialVersionUID, so we add the field to record
				// the serialVersionUID as we see it (mainly to make the Japi reports more realistic)
				writer.AddField(Modifiers.Private | Modifiers.Static | Modifiers.Final, "serialVersionUID", "J", SerialVersionUID.Compute(tw));
			}
			AddMetaAnnotations(writer, tw);
			writer.Write(stream);
		}

		private static void AddAnnotations(ClassFileWriter writer, IAttributeOwner target, MemberInfo source)
		{
#if !FIRST_PASS && !STUB_GENERATOR
			if (source != null)
			{
				RuntimeVisibleAnnotationsAttribute attr = null;
				foreach (CustomAttributeData cad in CustomAttributeData.GetCustomAttributes(source))
				{
					object[] ann = GetAnnotation(cad);
					if (ann != null)
					{
						if (attr == null)
						{
							attr = new RuntimeVisibleAnnotationsAttribute(writer);
						}
						attr.Add(ann);
					}
				}
				if (attr != null)
				{
					target.AddAttribute(attr);
				}
			}
#endif
		}

		private static void AddParameterAnnotations(ClassFileWriter writer, FieldOrMethod target, MethodBase source)
		{
#if !FIRST_PASS && !STUB_GENERATOR
			if (source != null)
			{
				RuntimeVisibleParameterAnnotationsAttribute attr = null;
				ParameterInfo[] parameters = source.GetParameters();
				for (int i = 0; i < parameters.Length; i++)
				{
					RuntimeVisibleAnnotationsAttribute param = null;
					foreach (CustomAttributeData cad in CustomAttributeData.GetCustomAttributes(parameters[i]))
					{
						object[] ann = GetAnnotation(cad);
						if (ann != null)
						{
							if (param == null)
							{
								if (attr == null)
								{
									attr = new RuntimeVisibleParameterAnnotationsAttribute(writer);
									for (int j = 0; j < i; j++)
									{
										attr.Add(new RuntimeVisibleAnnotationsAttribute(writer));
									}
								}
								param = new RuntimeVisibleAnnotationsAttribute(writer);
							}
							param.Add(ann);
						}
					}
					if (attr != null)
					{
						attr.Add(param ?? new RuntimeVisibleAnnotationsAttribute(writer));
					}
				}
				if (attr != null)
				{
					target.AddAttribute(attr);
				}
			}
#endif
		}

		private static void AddTypeAnnotations(ClassFileWriter writer, IAttributeOwner target, TypeWrapper tw, byte[] typeAnnotations)
		{
#if !FIRST_PASS && !STUB_GENERATOR
			if (typeAnnotations != null)
			{
				typeAnnotations = (byte[])typeAnnotations.Clone();
				object[] constantPool = tw.GetConstantPool();
				try
				{
					int pos = 0;
					ushort num_annotations = ReadUInt16BE(typeAnnotations, ref pos);
					for (int i = 0; i < num_annotations; i++)
					{
						FixupTypeAnnotationConstantPoolIndexes(writer, typeAnnotations, constantPool, ref pos);
					}
				}
				catch (IndexOutOfRangeException)
				{
					// if the attribute is malformed, we add it anyway and hope the Java parser will agree and throw the right error
				}
				target.AddAttribute(new RuntimeVisibleTypeAnnotationsAttribute(writer, typeAnnotations));
			}
#endif
		}

		private static void FixupTypeAnnotationConstantPoolIndexes(ClassFileWriter writer, byte[] typeAnnotations, object[] constantPool, ref int pos)
		{
			switch (typeAnnotations[pos++])		// target_type
			{
				case 0x00:
				case 0x01:
				case 0x16:
					pos++;
					break;
				case 0x10:
				case 0x11:
				case 0x12:
				case 0x17:
					pos += 2;
					break;
				case 0x13:
				case 0x14:
				case 0x15:
					break;
				default:
					throw new IndexOutOfRangeException();
			}
			byte path_length = typeAnnotations[pos++];
			pos += path_length * 2;
			FixupAnnotationConstantPoolIndexes(writer, typeAnnotations, constantPool, ref pos);
		}

		private static void FixupAnnotationConstantPoolIndexes(ClassFileWriter writer, byte[] typeAnnotations, object[] constantPool, ref int pos)
		{
			FixupConstantPoolIndex(writer, typeAnnotations, constantPool, ref pos);
			ushort num_components = ReadUInt16BE(typeAnnotations, ref pos);
			for (int i = 0; i < num_components; i++)
			{
				FixupConstantPoolIndex(writer, typeAnnotations, constantPool, ref pos);
				FixupAnnotationComponentValueConstantPoolIndexes(writer, typeAnnotations, constantPool, ref pos);
			}
		}

		private static void FixupConstantPoolIndex(ClassFileWriter writer, byte[] typeAnnotations, object[] constantPool, ref int pos)
		{
			ushort index = ReadUInt16BE(typeAnnotations, ref pos);
			object item = constantPool[index];
			if (item is int)
			{
				index = writer.AddInt((int)item);
			}
			else if (item is long)
			{
				index = writer.AddLong((long)item);
			}
			else if (item is float)
			{
				index = writer.AddFloat((float)item);
			}
			else if (item is double)
			{
				index = writer.AddDouble((double)item);
			}
			else if (item is string)
			{
				index = writer.AddUtf8((string)item);
			}
			else
			{
				throw new IndexOutOfRangeException();
			}
			typeAnnotations[pos - 2] = (byte)(index >> 8);
			typeAnnotations[pos - 1] = (byte)(index >> 0);
		}

		private static void FixupAnnotationComponentValueConstantPoolIndexes(ClassFileWriter writer, byte[] typeAnnotations, object[] constantPool, ref int pos)
		{
			switch ((char)typeAnnotations[pos++])	// tag
			{
				case 'B':
				case 'C':
				case 'D':
				case 'F':
				case 'I':
				case 'J':
				case 'S':
				case 'Z':
				case 's':
				case 'c':
					FixupConstantPoolIndex(writer, typeAnnotations, constantPool, ref pos);
					break;
				case 'e':
					FixupConstantPoolIndex(writer, typeAnnotations, constantPool, ref pos);
					FixupConstantPoolIndex(writer, typeAnnotations, constantPool, ref pos);
					break;
				case '@':
					FixupAnnotationConstantPoolIndexes(writer, typeAnnotations, constantPool, ref pos);
					break;
				case '[':
					ushort num_values = ReadUInt16BE(typeAnnotations, ref pos);
					for (int i = 0; i < num_values; i++)
					{
						FixupAnnotationComponentValueConstantPoolIndexes(writer, typeAnnotations, constantPool, ref pos);
					}
					break;
				default:
					throw new IndexOutOfRangeException();
			}
		}

		private static ushort ReadUInt16BE(byte[] buf, ref int pos)
		{
			ushort s = (ushort)((buf[pos] << 8) + buf[pos + 1]);
			pos += 2;
			return s;
		}

#if !FIRST_PASS && !STUB_GENERATOR
		private static object[] GetAnnotation(CustomAttributeData cad)
		{
			if (cad.ConstructorArguments.Count == 1 && cad.ConstructorArguments[0].ArgumentType == typeof(object[]) &&
				(cad.Constructor.DeclaringType.BaseType == typeof(ikvm.@internal.AnnotationAttributeBase)
				|| cad.Constructor.DeclaringType == typeof(DynamicAnnotationAttribute)))
			{
				return UnpackArray((IList<CustomAttributeTypedArgument>)cad.ConstructorArguments[0].Value);
			}
			else if (cad.Constructor.DeclaringType.BaseType == typeof(ikvm.@internal.AnnotationAttributeBase))
			{
				string annotationType = GetAnnotationInterface(cad);
				if (annotationType != null)
				{
					// this is a custom attribute annotation applied in a non-Java module
					List<object> list = new List<object>();
					list.Add(AnnotationDefaultAttribute.TAG_ANNOTATION);
					list.Add("L" + annotationType.Replace('.', '/') + ";");
					ParameterInfo[] parameters = cad.Constructor.GetParameters();
					for (int i = 0; i < parameters.Length; i++)
					{
						list.Add(parameters[i].Name);
						list.Add(EncodeAnnotationValue(cad.ConstructorArguments[i]));
					}
					foreach (CustomAttributeNamedArgument arg in cad.NamedArguments)
					{
						list.Add(arg.MemberInfo.Name);
						list.Add(EncodeAnnotationValue(arg.TypedValue));
					}
					return list.ToArray();
				}
			}
			return null;
		}

		private static string GetAnnotationInterface(CustomAttributeData cad)
		{
			object[] attr = cad.Constructor.DeclaringType.GetCustomAttributes(typeof(IKVM.Attributes.ImplementsAttribute), false);
			if (attr.Length == 1)
			{
				string[] interfaces = ((IKVM.Attributes.ImplementsAttribute)attr[0]).Interfaces;
				if (interfaces.Length == 1)
				{
					return interfaces[0];
				}
			}
			return null;
		}

		private static object EncodeAnnotationValue(CustomAttributeTypedArgument arg)
		{
			if (arg.ArgumentType.IsEnum)
			{
				// if GetWrapperFromType returns null, we've got an ikvmc synthesized .NET enum nested inside a Java enum
				TypeWrapper tw = ClassLoaderWrapper.GetWrapperFromType(arg.ArgumentType) ?? ClassLoaderWrapper.GetWrapperFromType(arg.ArgumentType.DeclaringType);
				return new object[] { AnnotationDefaultAttribute.TAG_ENUM, EncodeTypeName(tw), Enum.GetName(arg.ArgumentType, arg.Value) };
			}
			else if (arg.Value is Type)
			{
				return new object[] { AnnotationDefaultAttribute.TAG_CLASS, EncodeTypeName(ClassLoaderWrapper.GetWrapperFromType((Type)arg.Value)) };
			}
			else if (arg.ArgumentType.IsArray)
			{
				IList<CustomAttributeTypedArgument> array = (IList<CustomAttributeTypedArgument>)arg.Value;
				object[] arr = new object[array.Count + 1];
				arr[0] = AnnotationDefaultAttribute.TAG_ARRAY;
				for (int i = 0; i < array.Count; i++)
				{
					arr[i + 1] = EncodeAnnotationValue(array[i]);
				}
				return arr;
			}
			else
			{
				return arg.Value;
			}
		}

		private static string EncodeTypeName(TypeWrapper tw)
		{
			return tw.SigName.Replace('.', '/');
		}
#endif

		private static object[] UnpackArray(IList<CustomAttributeTypedArgument> list)
		{
			object[] arr = new object[list.Count];
			for (int i = 0; i < arr.Length; i++)
			{
				if (list[i].Value is IList<CustomAttributeTypedArgument>)
				{
					arr[i] = UnpackArray((IList<CustomAttributeTypedArgument>)list[i].Value);
				}
				else
				{
					arr[i] = list[i].Value;
				}
			}
			return arr;
		}

		private static int GetObsoleteCount(MethodBase mb)
		{
#if STUB_GENERATOR
			return mb.__GetCustomAttributes(JVM.Import(typeof(ObsoleteAttribute)), false).Count;
#else
			return mb.GetCustomAttributes(typeof(ObsoleteAttribute), false).Length;
#endif
		}

		private static CustomAttributeData GetAnnotationDefault(MethodBase mb)
		{
#if STUB_GENERATOR
			IList<CustomAttributeData> attr = CustomAttributeData.__GetCustomAttributes(mb, JVM.LoadType(typeof(AnnotationDefaultAttribute)), false);
			return attr.Count == 1 ? attr[0] : null;
#else
			foreach (CustomAttributeData cad in CustomAttributeData.GetCustomAttributes(mb))
			{
				if (cad.Constructor.DeclaringType == typeof(AnnotationDefaultAttribute))
				{
					return cad;
				}
			}
			return null;
#endif
		}

		private static string GetAssemblyName(TypeWrapper tw)
		{
			ClassLoaderWrapper loader = tw.GetClassLoader();
			AssemblyClassLoader acl = loader as AssemblyClassLoader;
			if (acl != null)
			{
				return acl.GetAssembly(tw).FullName;
			}
			else
			{
				return ((GenericClassLoaderWrapper)loader).GetName();
			}
		}

		private static bool IsSerializable(TypeWrapper tw)
		{
			if (tw.Name == "java.io.Serializable")
			{
				return true;
			}
			while (tw != null)
			{
				foreach (TypeWrapper iface in tw.Interfaces)
				{
					if (IsSerializable(iface))
					{
						return true;
					}
				}
				tw = tw.BaseTypeWrapper;
			}
			return false;
		}

		private static void AddMetaAnnotations(ClassFileWriter writer, TypeWrapper tw)
		{
			DotNetTypeWrapper.AttributeAnnotationTypeWrapperBase attributeAnnotation = tw as DotNetTypeWrapper.AttributeAnnotationTypeWrapperBase;
			if (attributeAnnotation != null)
			{
				// TODO write the annotation directly, instead of going thru the object[] encoding
				RuntimeVisibleAnnotationsAttribute annot = new RuntimeVisibleAnnotationsAttribute(writer);
				annot.Add(new object[] {
					AnnotationDefaultAttribute.TAG_ANNOTATION,
					"Ljava/lang/annotation/Retention;",
					"value",
					new object[] { AnnotationDefaultAttribute.TAG_ENUM, "Ljava/lang/annotation/RetentionPolicy;", "RUNTIME" }
				});
				AttributeTargets validOn = attributeAnnotation.AttributeTargets;
				List<object> targets = new List<object>();
				targets.Add(AnnotationDefaultAttribute.TAG_ARRAY);
				if ((validOn & (AttributeTargets.Class | AttributeTargets.Interface | AttributeTargets.Struct | AttributeTargets.Enum | AttributeTargets.Delegate | AttributeTargets.Assembly)) != 0)
				{
					targets.Add(new object[] { AnnotationDefaultAttribute.TAG_ENUM, "Ljava/lang/annotation/ElementType;", "TYPE" });
				}
				if ((validOn & AttributeTargets.Constructor) != 0)
				{
					targets.Add(new object[] { AnnotationDefaultAttribute.TAG_ENUM, "Ljava/lang/annotation/ElementType;", "CONSTRUCTOR" });
				}
				if ((validOn & AttributeTargets.Field) != 0)
				{
					targets.Add(new object[] { AnnotationDefaultAttribute.TAG_ENUM, "Ljava/lang/annotation/ElementType;", "FIELD" });
				}
				if ((validOn & (AttributeTargets.Method | AttributeTargets.ReturnValue)) != 0)
				{
					targets.Add(new object[] { AnnotationDefaultAttribute.TAG_ENUM, "Ljava/lang/annotation/ElementType;", "METHOD" });
				}
				if ((validOn & AttributeTargets.Parameter) != 0)
				{
					targets.Add(new object[] { AnnotationDefaultAttribute.TAG_ENUM, "Ljava/lang/annotation/ElementType;", "PARAMETER" });
				}
				annot.Add(new object[] {
					AnnotationDefaultAttribute.TAG_ANNOTATION,
					"Ljava/lang/annotation/Target;",
					"value",
					targets.ToArray()
				});
				if (IsRepeatableAnnotation(tw))
				{
					annot.Add(new object[] {
						AnnotationDefaultAttribute.TAG_ANNOTATION,
						"Ljava/lang/annotation/Repeatable;",
						"value",
						new object[] { AnnotationDefaultAttribute.TAG_CLASS, "L" + (tw.Name + DotNetTypeWrapper.AttributeAnnotationMultipleSuffix).Replace('.', '/') + ";" }
					});
				}
				writer.AddAttribute(annot);
			}
		}

		private static bool IsRepeatableAnnotation(TypeWrapper tw)
		{
			foreach (TypeWrapper nested in tw.InnerClasses)
			{
				if (nested.Name == tw.Name + DotNetTypeWrapper.AttributeAnnotationMultipleSuffix)
				{
					return true;
				}
			}
			return false;
		}

		private static byte[] GetAnnotationDefault(ClassFileWriter classFile, TypeWrapper type)
		{
			MemoryStream mem = new MemoryStream();
			BigEndianStream bes = new BigEndianStream(mem);
			if (type == PrimitiveTypeWrapper.BOOLEAN)
			{
				bes.WriteByte((byte)'Z');
				bes.WriteUInt16(classFile.AddInt(0));
			}
			else if (type == PrimitiveTypeWrapper.BYTE)
			{
				bes.WriteByte((byte)'B');
				bes.WriteUInt16(classFile.AddInt(0));
			}
			else if (type == PrimitiveTypeWrapper.CHAR)
			{
				bes.WriteByte((byte)'C');
				bes.WriteUInt16(classFile.AddInt(0));
			}
			else if (type == PrimitiveTypeWrapper.SHORT)
			{
				bes.WriteByte((byte)'S');
				bes.WriteUInt16(classFile.AddInt(0));
			}
			else if (type == PrimitiveTypeWrapper.INT)
			{
				bes.WriteByte((byte)'I');
				bes.WriteUInt16(classFile.AddInt(0));
			}
			else if (type == PrimitiveTypeWrapper.FLOAT)
			{
				bes.WriteByte((byte)'F');
				bes.WriteUInt16(classFile.AddFloat(0));
			}
			else if (type == PrimitiveTypeWrapper.LONG)
			{
				bes.WriteByte((byte)'J');
				bes.WriteUInt16(classFile.AddLong(0));
			}
			else if (type == PrimitiveTypeWrapper.DOUBLE)
			{
				bes.WriteByte((byte)'D');
				bes.WriteUInt16(classFile.AddDouble(0));
			}
			else if (type == CoreClasses.java.lang.String.Wrapper)
			{
				bes.WriteByte((byte)'s');
				bes.WriteUInt16(classFile.AddUtf8(""));
			}
			else if ((type.Modifiers & Modifiers.Enum) != 0)
			{
				bes.WriteByte((byte)'e');
				bes.WriteUInt16(classFile.AddUtf8("L" + type.Name.Replace('.', '/') + ";"));
				bes.WriteUInt16(classFile.AddUtf8("__unspecified"));
			}
			else if (type == CoreClasses.java.lang.Class.Wrapper)
			{
				bes.WriteByte((byte)'c');
				bes.WriteUInt16(classFile.AddUtf8("Likvm/internal/__unspecified;"));
			}
			else if (type.IsArray)
			{
				bes.WriteByte((byte)'[');
				bes.WriteUInt16(0);
			}
			else
			{
				throw new InvalidOperationException();
			}
			return mem.ToArray();
		}

		private static byte[] GetAnnotationDefault(ClassFileWriter classFile, CustomAttributeTypedArgument value)
		{
			MemoryStream mem = new MemoryStream();
			BigEndianStream bes = new BigEndianStream(mem);
			try
			{
				WriteAnnotationElementValue(classFile, bes, value);
			}
			catch (InvalidCastException)
			{
				Warning("Warning: incorrect annotation default value");
			}
			catch (IndexOutOfRangeException)
			{
				Warning("Warning: incorrect annotation default value");
			}
			return mem.ToArray();
		}

		private static void WriteAnnotationElementValue(ClassFileWriter classFile, BigEndianStream bes, CustomAttributeTypedArgument value)
		{
			if (value.ArgumentType == Types.Boolean)
			{
				bes.WriteByte((byte)'Z');
				bes.WriteUInt16(classFile.AddInt((bool)value.Value ? 1 : 0));
			}
			else if (value.ArgumentType == Types.Byte)
			{
				bes.WriteByte((byte)'B');
				bes.WriteUInt16(classFile.AddInt((byte)value.Value));
			}
			else if (value.ArgumentType == Types.Char)
			{
				bes.WriteByte((byte)'C');
				bes.WriteUInt16(classFile.AddInt((char)value.Value));
			}
			else if (value.ArgumentType == Types.Int16)
			{
				bes.WriteByte((byte)'S');
				bes.WriteUInt16(classFile.AddInt((short)value.Value));
			}
			else if (value.ArgumentType == Types.Int32)
			{
				bes.WriteByte((byte)'I');
				bes.WriteUInt16(classFile.AddInt((int)value.Value));
			}
			else if (value.ArgumentType == Types.Single)
			{
				bes.WriteByte((byte)'F');
				bes.WriteUInt16(classFile.AddFloat((float)value.Value));
			}
			else if (value.ArgumentType == Types.Int64)
			{
				bes.WriteByte((byte)'J');
				bes.WriteUInt16(classFile.AddLong((long)value.Value));
			}
			else if (value.ArgumentType == Types.Double)
			{
				bes.WriteByte((byte)'D');
				bes.WriteUInt16(classFile.AddDouble((double)value.Value));
			}
			else if (value.ArgumentType == Types.String)
			{
				bes.WriteByte((byte)'s');
				bes.WriteUInt16(classFile.AddUtf8((string)value.Value));
			}
			else if (value.ArgumentType == Types.Object.MakeArrayType())
			{
				CustomAttributeTypedArgument[] array = (CustomAttributeTypedArgument[])value.Value;
				byte type = (byte)array[0].Value;
				if (type == AnnotationDefaultAttribute.TAG_ARRAY)
				{
					bes.WriteByte((byte)'[');
					bes.WriteUInt16((ushort)(array.Length - 1));
					for (int i = 1; i < array.Length; i++)
					{
						WriteAnnotationElementValue(classFile, bes, array[i]);
					}
				}
				else if (type == AnnotationDefaultAttribute.TAG_CLASS)
				{
					bes.WriteByte((byte)'c');
					bes.WriteUInt16(classFile.AddUtf8((string)array[1].Value));
				}
				else if (type == AnnotationDefaultAttribute.TAG_ENUM)
				{
					bes.WriteByte((byte)'e');
					bes.WriteUInt16(classFile.AddUtf8((string)array[1].Value));
					bes.WriteUInt16(classFile.AddUtf8((string)array[2].Value));
				}
				else if (type == AnnotationDefaultAttribute.TAG_ANNOTATION)
				{
					bes.WriteByte((byte)'@');
					bes.WriteUInt16(classFile.AddUtf8((string)array[1].Value));
					bes.WriteUInt16((ushort)((array.Length - 2) / 2));
					for (int i = 2; i < array.Length; i += 2)
					{
						bes.WriteUInt16(classFile.AddUtf8((string)array[i].Value));
						WriteAnnotationElementValue(classFile, bes, array[i + 1]);
					}
				}
				else
				{
					Warning("Warning: incorrect annotation default element tag: " + type);
				}
			}
			else
			{
				Warning("Warning: incorrect annotation default element type: " + value.ArgumentType);
			}
		}

		private static void Warning(string message)
		{
#if STUB_GENERATOR
			Console.Error.WriteLine(message);
#endif
		}
	}
}
