internal AttemptTuple <MapperDefinition> TryGetMapper(Type source, Type target, bool createIfNonExistant)
{
Func <AttemptTuple <MapperDefinition> > findTypeMapper = () =>
{
//if we have a specified TypeMapper for <TSource,Target>
MapperDefinition mapper;
if (_mappers.TryGetValue(new TypeMapDefinition(source, target), out mapper))
{
return(new AttemptTuple <MapperDefinition>(true, mapper));
}
//now, check if we have the specified mapper using type inheritance
var found = _mappers.Where(x => x.Value.Metadata.PermitTypeInheritance && x.Value.Metadata.SourceType.IsAssignableFrom(source) &&
x.Value.Metadata.DestinationType.IsAssignableFrom(target)).ToArray();
if (found.Any())
{
return(new AttemptTuple <MapperDefinition>(true, found.Single().Value));
}
return(AttemptTuple <MapperDefinition> .False);
};
var result = findTypeMapper();
if (result.Success)
{
return(result);
}
//if we've got this far, then create a new default map and add it to our mappers
if (createIfNonExistant)
{
//need to lock as there could be many threads trying to do the same thing with the same types
using (new WriteLockDisposable(_locker))
{
//we'll now actually need to re-check if it exists
result = findTypeMapper();
if (result.Success)
{
return(result);
}
//if both Source and Target types are Enumerables return new EnumerableTypeMapper<TSource,TTarget>()
if (source.IsEnumerable() && target.IsEnumerable())
{
var mapper = (ITypeMapper)
Activator.CreateInstance(typeof(EnumerableTypeMapper <,>).MakeGenericType(source, target)
, this); //pass this factory into the constructor
//create the map and store it against our list
var meta = new TypeMapperMetadata(source, target, false);
var mapperDef = new MapperDefinition(mapper, meta);
return(new AttemptTuple <MapperDefinition>(true,
_mappers.GetOrAdd(new TypeMapDefinition(source, target), mapperDef)));
}
else
{
//if not enumerable, just create a normal map
var concreteTypeMapper = typeof(TypeMapper <,>).MakeGenericType(new[] { source, target });
var mapper = (ITypeMapper)Creator.Create(concreteTypeMapper, this);
var defaultMeta = new TypeMapperMetadata(source, target, false);
var defaultMapperDef = new MapperDefinition(mapper, defaultMeta);
return(new AttemptTuple <MapperDefinition>(true,
_mappers.GetOrAdd(new TypeMapDefinition(source, target), defaultMapperDef)));
}
}
}
return(AttemptTuple <MapperDefinition> .False);
}
