public MultiTraitContext()
{
_empty = new MultiTrait(this);
_traits = new ConcurrentDictionary <string, MultiTrait>(StringComparer.Ordinal);
_traits[String.Empty] = _empty;
_creationLock = new Object();
}
MultiTrait FindOrCreate(string traits, bool create)
{
if (traits == null || traits.Length == 0)
{
return(_empty);
}
traits = traits.Normalize();
MultiTrait m;
if (!_traits.TryGetValue(traits, out m))
{
int traitCount;
string[] splitTraits = SplitMultiTrait(traits, out traitCount);
if (traitCount <= 0)
{
return(_empty);
}
if (traitCount == 1)
{
m = FindOrCreateAtomicTrait(splitTraits[0], create);
}
else
{
traits = String.Join("+", splitTraits, 0, traitCount);
if (!_traits.TryGetValue(traits, out m))
{
MultiTrait[] atomics = new MultiTrait[traitCount];
for (int i = 0; i < traitCount; ++i)
{
MultiTrait trait = FindOrCreateAtomicTrait(splitTraits[i], create);
if ((atomics[i] = trait) == null)
{
return(null);
}
}
lock ( _creationLock )
{
if (!_traits.TryGetValue(traits, out m))
{
m = new MultiTrait(this, traits, new ReadOnlyListOnIList <MultiTrait>(atomics));
_traits[traits] = m;
}
}
}
Debug.Assert(!m.IsAtomic && m.AtomicTraits.Count == traitCount, "Combined trait.");
}
}
return(m);
}
private MultiTrait FindOrCreateAtomicTrait(string trait, bool create)
{
MultiTrait m;
if (!_traits.TryGetValue(trait, out m) && create)
{
lock ( _creationLock )
{
if (!_traits.TryGetValue(trait, out m))
{
m = new MultiTrait(this, trait);
_traits[trait] = m;
}
}
Debug.Assert(m.IsAtomic, "Special construction for atomic traits.");
}
return(m);
}
/// <summary>
/// Obtains a trait from a list of atomic (already sorted) traits.
/// Used by fall back generation.
/// </summary>
internal MultiTrait FindOrCreate(MultiTrait[] atomicTraits, int count)
{
Debug.Assert(count > 1, "Atomic traits are handled directly.");
Debug.Assert(!Array.Exists(atomicTraits, delegate(MultiTrait mA) { return(mA.Context != this || mA.AtomicTraits.Count != 1); }),
"Traits are from this Context and they are atomic and not empty.");
StringBuilder b = new StringBuilder(atomicTraits[0].ToString());
for (int i = 1; i < count; ++i)
{
Debug.Assert(StringComparer.Ordinal.Compare(atomicTraits[i - 1].ToString(), atomicTraits[i].ToString()) < 0, "Traits are already sorted and NO DUPLICATE exists.");
b.Append('+').Append(atomicTraits[i].ToString());
}
string traits = b.ToString();
MultiTrait m;
if (!_traits.TryGetValue(traits, out m))
{
// We must clone the array since fallback generation reuses it.
if (atomicTraits.Length != count)
{
MultiTrait[] subArray = new MultiTrait[count];
Array.Copy(atomicTraits, subArray, count);
atomicTraits = subArray;
}
else
{
atomicTraits = (MultiTrait[])atomicTraits.Clone();
}
lock ( _creationLock )
{
if (!_traits.TryGetValue(traits, out m))
{
m = new MultiTrait(this, traits, new ReadOnlyListOnIList <MultiTrait>(atomicTraits));
_traits[traits] = m;
}
}
}
return(m);
}
/// <summary>
/// Obtains a trait from a list of atomic (already sorted) traits.
/// Used by the Add, Toggle, Remove, Intersect methods.
/// </summary>
internal MultiTrait FindOrCreate(List <MultiTrait> atomicTraits)
{
if (atomicTraits.Count == 0)
{
return(_empty);
}
Debug.Assert(atomicTraits[0].Context == this, "This is one of our traits.");
Debug.Assert(atomicTraits[0].AtomicTraits.Count == 1, "This is an atomic trait and not the empty one.");
if (atomicTraits.Count == 1)
{
return(atomicTraits[0]);
}
StringBuilder b = new StringBuilder(atomicTraits[0].ToString());
for (int i = 1; i < atomicTraits.Count; ++i)
{
Debug.Assert(atomicTraits[i].Context == this, "This is one of our traits.");
Debug.Assert(atomicTraits[i].AtomicTraits.Count == 1, "This is an atomic trait and not the empty one.");
Debug.Assert(StringComparer.Ordinal.Compare(atomicTraits[i - 1].ToString(), atomicTraits[i].ToString()) < 0,
"Traits are already sorted and NO DUPLICATES exist.");
b.Append('+').Append(atomicTraits[i].ToString());
}
string traits = b.ToString();
MultiTrait m;
if (!_traits.TryGetValue(traits, out m))
{
lock ( _creationLock )
{
if (!_traits.TryGetValue(traits, out m))
{
m = new MultiTrait(this, traits, new ReadOnlyListOnIList <MultiTrait>(atomicTraits.ToArray()));
_traits[traits] = m;
}
}
}
return(m);
}
/// <summary>
/// Finds a <see cref="MultiTrait"/> with only already existing atomic traits.
/// </summary>
/// <param name="traits">Atomic trait or traits separated by +.</param>
/// <param name="collector">Optional collector for unknown trait. As soon as the collector returns false, the process stops.</param>
/// <returns>A trait that contains only already existing traits or null if none already exists.</returns>
public MultiTrait FindOnlyExisting(string traits, Func <string, bool> collector = null)
{
if (traits == null || traits.Length == 0)
{
return(null);
}
traits = traits.Normalize();
MultiTrait m;
if (!_traits.TryGetValue(traits, out m))
{
int traitCount;
string[] splitTraits = SplitMultiTrait(traits, out traitCount);
if (traitCount <= 0)
{
return(null);
}
if (traitCount == 1)
{
m = FindOrCreateAtomicTrait(splitTraits[0], false);
}
else
{
traits = String.Join("+", splitTraits, 0, traitCount);
if (!_traits.TryGetValue(traits, out m))
{
List <MultiTrait> atomics = new List <MultiTrait>();
for (int i = 0; i < traitCount; ++i)
{
MultiTrait trait = FindOrCreateAtomicTrait(splitTraits[i], false);
if (trait == null)
{
if (collector != null && !collector(splitTraits[i]))
{
break;
}
}
else
{
atomics.Add(trait);
}
}
if (atomics.Count != 0)
{
traits = String.Join("+", atomics);
if (!_traits.TryGetValue(traits, out m))
{
lock ( _creationLock )
{
if (!_traits.TryGetValue(traits, out m))
{
m = new MultiTrait(this, traits, atomics.ToReadOnlyList());
_traits[traits] = m;
}
}
}
}
}
}
}
return(m);
}