#region Copyright notice and license
// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc. All rights reserved.
// http://github.com/jskeet/dotnet-protobufs/
// Original C++/Java/Python code:
// http://code.google.com/p/protobuf/
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#endregion
using System;
using System.Collections.Generic;
namespace Google.ProtocolBuffers
{
///<summary>
///Interface for an enum value or value descriptor, to be used in FieldSet.
///The lite library stores enum values directly in FieldSets but the full
///library stores EnumValueDescriptors in order to better support reflection.
///</summary>
public interface IEnumLite
{
int Number { get; }
string Name { get; }
}
///<summary>
///Interface for an object which maps integers to {@link EnumLite}s.
///{@link Descriptors.EnumDescriptor} implements this interface by mapping
///numbers to {@link Descriptors.EnumValueDescriptor}s. Additionally,
///every generated enum type has a static method internalGetValueMap() which
///returns an implementation of this type that maps numbers to enum values.
///</summary>
public interface IEnumLiteMap<T> : IEnumLiteMap
where T : IEnumLite
{
new T FindValueByNumber(int number);
}
public interface IEnumLiteMap
{
bool IsValidValue(IEnumLite value);
IEnumLite FindValueByNumber(int number);
IEnumLite FindValueByName(string name);
}
public class EnumLiteMap<TEnum> : IEnumLiteMap<IEnumLite>
where TEnum : struct, IComparable, IFormattable
{
private struct EnumValue : IEnumLite
{
private readonly TEnum value;
public EnumValue(TEnum value)
{
this.value = value;
}
int IEnumLite.Number
{
get { return Convert.ToInt32(value); }
}
string IEnumLite.Name
{
get { return value.ToString(); }
}
}
public IEnumLite FindValueByNumber(int number)
{
TEnum val = default(TEnum);
if (EnumParser<TEnum>.TryConvert(number, ref val))
{
return new EnumValue(val);
}
return null;
}
public IEnumLite FindValueByName(string name)
{
TEnum val = default(TEnum);
if (EnumParser<TEnum>.TryConvert(name, ref val))
{
return new EnumValue(val);
}
return null;
}
public bool IsValidValue(IEnumLite value)
{
TEnum val = default(TEnum);
return EnumParser<TEnum>.TryConvert(value.Number, ref val);
}
}
public static class EnumParser<T> where T : struct, IComparable, IFormattable
{
private static readonly Dictionary<int, T> _byNumber;
private static Dictionary<string, T> _byName;
static EnumParser()
{
int[] array;
try
{
#if CLIENTPROFILE
// It will actually be a T[], but the CLR will let us convert.
array = (int[])Enum.GetValues(typeof(T));
#else
var temp = new List<T>();
foreach (var fld in typeof (T).GetFields(System.Reflection.BindingFlags.Public | System.Reflection.BindingFlags.Static))
{
if (fld.IsLiteral && fld.FieldType == typeof(T))
{
temp.Add((T)fld.GetValue(null));
}
}
array = (int[])(object)temp.ToArray();
#endif
}
catch
{
_byNumber = null;
return;
}
_byNumber = new Dictionary<int, T>(array.Length);
foreach (int i in array)
{
_byNumber[i] = (T)(object)i;
}
}
public static bool TryConvert(object input, ref T value)
{
if (input is int || input is T)
{
return TryConvert((int)input, ref value);
}
if (input is string)
{
return TryConvert((string)input, ref value);
}
return false;
}
/// <summary>
/// Tries to convert an integer to its enum representation. This would take an out parameter,
/// but the caller uses ref, so this approach is simpler.
/// </summary>
public static bool TryConvert(int number, ref T value)
{
// null indicates an exception at construction, use native IsDefined.
if (_byNumber == null)
{
return Enum.IsDefined(typeof(T), number);
}
T converted;
if (_byNumber != null && _byNumber.TryGetValue(number, out converted))
{
value = converted;
return true;
}
return false;
}
/// <summary>
/// Tries to convert a string to its enum representation. This would take an out parameter,
/// but the caller uses ref, so this approach is simpler.
/// </summary>
public static bool TryConvert(string name, ref T value)
{
// null indicates an exception at construction, use native IsDefined/Parse.
if (_byNumber == null)
{
if (Enum.IsDefined(typeof(T), name))
{
value = (T)Enum.Parse(typeof(T), name, false);
return true;
}
return false;
}
// known race, possible multiple threads each build their own copy; however, last writer will win
var map = _byName;
if (map == null)
{
map = new Dictionary<string, T>(StringComparer.Ordinal);
foreach (var possible in _byNumber.Values)
{
map[possible.ToString()] = possible;
}
_byName = map;
}
T converted;
if (map.TryGetValue(name, out converted))
{
value = converted;
return true;
}
return false;
}
}
}
