public ICaexViewModelFactory GetFactory <T>(ICAEXWrapper model) where T : CaexObjectViewModel
{
var factories = new List <ICaexViewModelFactory>();
foreach (var factory in _factories)
{
// only factories that can create the destination type
var canCreateDestinationType = factory.CanCreate <T>(model);
if (!canCreateDestinationType)
{
continue;
}
// only factories that can handle the given CAEX object
if (factory.TypeOfViewModel(model) == null)
{
continue;
}
factories.Add(factory);
}
if (factories.Count == 0)
{
return(null);
}
if (factories.Count == 1)
{
return(factories[0]);
}
ICaexViewModelFactory match = null;
foreach (var factory in factories)
{
var hasSubClass = false;
foreach (var f in factories)
{
var thisType = factory.TypeOfViewModel(model);
var otherType = f.TypeOfViewModel(model);
if (otherType.IsSubclassOf(thisType))
{
hasSubClass = true;
}
}
if (!hasSubClass)
{
if (match != null)
{
throw new Exception("Multiple factories found");
}
match = factory;
}
}
if (match == null)
{
throw new Exception("Weird: factory missing for type " + model.GetType());
}
return(match);
}
public void Register(ICaexViewModelFactory factory)
{
_factories.Add(factory);
}