ArraySegmentMessageSerializer.cs

#region -- License Terms --
//
// MessagePack for CLI
//
// Copyright (C) 2010-2012 FUJIWARA, Yusuke
//
//    Licensed under the Apache License, Version 2.0 (the "License");
//    you may not use this file except in compliance with the License.
//    You may obtain a copy of the License at
//
//        http://www.apache.org/licenses/LICENSE-2.0
//
//    Unless required by applicable law or agreed to in writing, software
//    distributed under the License is distributed on an "AS IS" BASIS,
//    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//    See the License for the specific language governing permissions and
//    limitations under the License.
//
#endregion -- License Terms --

using System;
using System.Linq;
using System.Reflection;
using System.Diagnostics.CodeAnalysis;

namespace MsgPack.Serialization.DefaultSerializers
{
	internal static class ArraySegmentMessageSerializer
	{
		public static readonly MethodInfo PackByteArraySegmentToMethod =
			FromExpression.ToMethod( ( Packer packer, ArraySegment<byte> objectTree, MessagePackSerializer<byte> itemSerializer ) => PackByteArraySegmentTo( packer, objectTree, itemSerializer ) );
		public static readonly MethodInfo PackCharArraySegmentToMethod =
			FromExpression.ToMethod( ( Packer packer, ArraySegment<char> objectTree, MessagePackSerializer<char> itemSerializer ) => PackCharArraySegmentTo( packer, objectTree, itemSerializer ) );
		public static readonly MethodInfo PackGenericArraySegmentTo1Method =
			typeof( ArraySegmentMessageSerializer ).GetMethod( "PackGenericArraySegmentTo" );
		public static readonly MethodInfo UnpackByteArraySegmentFromMethod =
			FromExpression.ToMethod( ( Unpacker unpacker, MessagePackSerializer<byte> itemSerializer ) => UnpackByteArraySegmentFrom( unpacker, itemSerializer ) );
		public static readonly MethodInfo UnpackCharArraySegmentFromMethod =
			FromExpression.ToMethod( ( Unpacker unpacker, MessagePackSerializer<char> itemSerializer ) => UnpackCharArraySegmentFrom( unpacker, itemSerializer ) );
		public static readonly MethodInfo UnpackGenericArraySegmentFrom1Method =
			typeof( ArraySegmentMessageSerializer ).GetMethod( "UnpackGenericArraySegmentFrom" );

		[SuppressMessage( "Microsoft.Usage", "CA1801:ReviewUnusedParameters", MessageId = "itemSerializer", Justification = "For Delegate signature compatibility" )]
		public static void PackByteArraySegmentTo( Packer packer, ArraySegment<byte> objectTree, MessagePackSerializer<byte> itemSerializer )
		{
			if ( objectTree.Array == null )
			{
				packer.PackBinaryHeader( 0 );
				return;
			}

			packer.PackBinaryHeader( objectTree.Count );
			packer.PackRawBody( objectTree.Array.Skip( objectTree.Offset ).Take( objectTree.Count ) );
		}

		[SuppressMessage( "Microsoft.Usage", "CA1801:ReviewUnusedParameters", MessageId = "itemSerializer", Justification = "For Delegate signature compatibility" )]
		public static void PackCharArraySegmentTo( Packer packer, ArraySegment<char> objectTree, MessagePackSerializer<char> itemSerializer )
		{
			// TODO: More efficient
			packer.PackStringHeader( objectTree.Count );
			packer.PackRawBody( MessagePackConvert.EncodeString( new string( objectTree.Array.Skip( objectTree.Offset ).Take( objectTree.Count ).ToArray() ) ) );
		}

		public static void PackGenericArraySegmentTo<T>( Packer packer, ArraySegment<T> objectTree, MessagePackSerializer<T> itemSerializer )
		{
			packer.PackArrayHeader( objectTree.Count );
			for ( int i = 0; i < objectTree.Count; i++ )
			{
				itemSerializer.PackTo( packer, objectTree.Array[ i + objectTree.Offset ] );
			}
		}

		[SuppressMessage( "Microsoft.Usage", "CA1801:ReviewUnusedParameters", MessageId = "itemSerializer", Justification = "For Delegate signature compatibility" )]
		public static ArraySegment<byte> UnpackByteArraySegmentFrom( Unpacker unpacker, MessagePackSerializer<byte> itemSerializer )
		{
			return new ArraySegment<byte>( unpacker.LastReadData.AsBinary() );
		}

		[SuppressMessage( "Microsoft.Usage", "CA1801:ReviewUnusedParameters", MessageId = "itemSerializer", Justification = "For Delegate signature compatibility" )]
		public static ArraySegment<char> UnpackCharArraySegmentFrom( Unpacker unpacker, MessagePackSerializer<char> itemSerializer )
		{
			// TODO: More efficient
			return new ArraySegment<char>( unpacker.LastReadData.AsCharArray() );
		}

		public static ArraySegment<T> UnpackGenericArraySegmentFrom<T>( Unpacker unpacker, MessagePackSerializer<T> itemSerializer )
		{
			T[] array = new T[ unpacker.ItemsCount ];
			for ( int i = 0; i < array.Length; i++ )
			{
				if ( !unpacker.Read() )
				{
					throw SerializationExceptions.NewMissingItem( i );
				}

				array[ i ] = itemSerializer.UnpackFrom( unpacker );
			}

			return new ArraySegment<T>( array );
		}
	}
}