internal static Position processAddSourceItem(int newSourceIndex, bool predicateValue, ref Position newItemPosition,
ref int?newFilteredIndex, List <FilteringItemInfo> filteringItemInfos, Positions <Position> filteredPositions, int count)
{
Position nextItemPosition;
if (newSourceIndex < filteringItemInfos.Count)
{
FilteringItemInfo oldItemInfo = filteringItemInfos[newSourceIndex];
Position oldItemInfoNextFilteredItemPosition = oldItemInfo.NextFilteredItemPosition;
Position oldItemInfoFilteredPosition = oldItemInfo.FilteredPosition;
if (predicateValue)
{
if (oldItemInfoFilteredPosition == null)
{
newItemPosition = filteredPositions.Insert(oldItemInfoNextFilteredItemPosition.Index);
nextItemPosition = oldItemInfoNextFilteredItemPosition;
newFilteredIndex = newItemPosition.Index;
}
else
{
int filteredIndex = oldItemInfoFilteredPosition.Index;
newFilteredIndex = filteredIndex;
newItemPosition = filteredPositions.Insert(filteredIndex);
nextItemPosition = oldItemInfoFilteredPosition;
}
modifyNextFilteredItemIndex(newSourceIndex, newItemPosition, filteringItemInfos);
}
else
{
nextItemPosition = oldItemInfoFilteredPosition ?? oldItemInfoNextFilteredItemPosition;
}
}
else
{
if (predicateValue)
{
newItemPosition = filteredPositions.List[count];
newFilteredIndex = count;
nextItemPosition = filteredPositions.Add();
}
else
{
//здесь newPositionIndex = null; так и должно быть
nextItemPosition = filteredPositions.List[count];
}
}
return(nextItemPosition);
}
//TODO Uncomment new feature and write test
//[ObservableComputationsCall]
//public Filtering<TSourceItem> TryConstructInsertOrRemoveRequestHandlers()
//{
// ConstructInsertOrRemoveActionsVisitor
// constructInsertOrRemoveActionsVisitor =
// new ConstructInsertOrRemoveActionsVisitor();
// constructInsertOrRemoveActionsVisitor.Visit(_predicateExpressionOriginal);
// Action<TSourceItem> transformSourceItemIntoMember =
// constructInsertOrRemoveActionsVisitor.TransformSourceItemIntoMember;
// if (transformSourceItemIntoMember != null)
// {
// InsertItemRequestHandler = (index, item) => transformSourceItemIntoMember(item);
// }
// Action<TSourceItem> transformSourceItemNotIntoMember =
// constructInsertOrRemoveActionsVisitor.TransformSourceItemIntoNotMember;
// if (transformSourceItemNotIntoMember != null)
// {
// RemoveItemRequestHandler = index => transformSourceItemNotIntoMember(this[index]);
// }
// return this;
//}
//private class ConstructInsertOrRemoveActionsVisitor : ExpressionVisitor
//{
// public Action<TSourceItem> TransformSourceItemIntoMember;
// public Action<TSourceItem> TransformSourceItemIntoNotMember;
// #region Overrides of ExpressionVisitor
// //TODO !sourceItem.NullableProp.HasValue должно преобразооваться в sourceItem.NullableProp == null
// // TODO обрабытывать выражения типа '25 == sourceItem.Id'
// protected override Expression VisitBinary(BinaryExpression node)
// {
// ExpressionType nodeType = node.NodeType;
// if (nodeType == ExpressionType.Equal || nodeType == ExpressionType.NotEqual)
// {
// if (node.Left is MemberExpression memberExpression)
// {
// Expression rightExpression = node.Right;
// // ReSharper disable once PossibleNullReferenceException
// MemberInfo memberExpressionMember = memberExpression.Member;
// Type declaringType = memberExpressionMember.DeclaringType;
// // ReSharper disable once PossibleNullReferenceException
// if (declaringType.IsConstructedGenericType
// && declaringType.GetGenericTypeDefinition() == typeof(Nullable<>)
// && memberExpressionMember.Name == "Value")
// {
// memberExpression = (MemberExpression) memberExpression.Expression;
// rightExpression = Expression.Convert(rightExpression,
// typeof (Nullable<>).MakeGenericType(node.Left.Type));
// }
// ParameterExpression parameterExpression = getParameterExpression(memberExpression);
// if (parameterExpression != null)
// {
// if (memberExpression.Type != rightExpression.Type)
// {
// rightExpression = Expression.Convert(rightExpression, memberExpression.Type);
// }
// if (!memberExpressionMember.IsReadOnly())
// {
// if (nodeType == ExpressionType.Equal)
// {
// TransformSourceItemIntoMember = Expression.Lambda<Action<TSourceItem>>(Expression.Assign(memberExpression, rightExpression), parameterExpression).Compile();
// }
// else if (nodeType == ExpressionType.NotEqual)
// {
// TransformSourceItemIntoNotMember = Expression.Lambda<Action<TSourceItem>>(Expression.Assign(memberExpression, rightExpression), parameterExpression).Compile();
// }
// }
// }
// }
// }
// return node;
// }
// private ParameterExpression getParameterExpression(MemberExpression memberExpression)
// {
// if (memberExpression.Expression is ParameterExpression parameterExpression)
// {
// return parameterExpression;
// }
// if (memberExpression.Expression is MemberExpression expressionMemberExpression)
// {
// return getParameterExpression(expressionMemberExpression); // memberExpression.Expression может быть не MemberExpression
// }
// return null;
// }
// #endregion
//}
protected override void processSource()
{
int originalCount = _items.Count;
if (_sourceReadAndSubscribed)
{
Utils.disposeExpressionItemInfos(_itemInfos, _predicateExpressionCallCount, this);
Utils.removeDownstreamConsumedComputing(_itemInfos, this);
_filteredPositions = new Positions <Position>(new List <Position>(_initialCapacity));
Utils.disposeSource(
_sourceScalar,
_source,
out _itemInfos,
out _sourcePositions,
_sourceAsList,
handleSourceCollectionChanged);
_sourceReadAndSubscribed = false;
}
Utils.changeSource(ref _source, _sourceScalar, _downstreamConsumedComputings, _consumers, this, out _sourceAsList, false);
if (_source != null && _isActive)
{
Utils.initializeFromObservableCollectionWithChangeMarker(
_source,
ref _sourceAsList,
ref _rootSourceWrapper,
ref _lastProcessedSourceChangeMarker);
Position nextItemPosition = _filteredPositions.Add();
int count = _sourceAsList.Count;
TSourceItem[] sourceCopy = new TSourceItem[count];
_sourceAsList.CopyTo(sourceCopy, 0);
_sourceAsList.CollectionChanged += handleSourceCollectionChanged;
int insertingIndex = 0;
int sourceIndex;
for (sourceIndex = 0; sourceIndex < count; sourceIndex++)
{
TSourceItem sourceItem = sourceCopy[sourceIndex];
Position currentFilteredItemPosition = null;
FilteringItemInfo itemInfo = registerSourceItem(sourceItem, sourceIndex, null, null);
if (_thisAsFiltering.applyPredicate(sourceItem, itemInfo.PredicateFunc))
{
if (originalCount > insertingIndex)
{
_items[insertingIndex++] = sourceItem;
}
else
{
_items.Insert(insertingIndex++, sourceItem);
}
currentFilteredItemPosition = nextItemPosition;
nextItemPosition = _filteredPositions.Add();
}
itemInfo.FilteredPosition = currentFilteredItemPosition;
itemInfo.NextFilteredItemPosition = nextItemPosition;
}
for (int index = originalCount - 1; index >= insertingIndex; index--)
{
_items.RemoveAt(index);
}
_sourceReadAndSubscribed = true;
}
else
{
_items.Clear();
}
reset();
}
private void initializeFromSource()
{
int originalCount = _items.Count;
if (_sourceNotifyCollectionChangedEventHandler != null)
{
int itemInfosCount = _itemInfos.Count;
for (int index = 0; index < itemInfosCount; index++)
{
ItemInfo itemInfo = _itemInfos[index];
ExpressionWatcher expressionWatcher = itemInfo.ExpressionWatcher;
expressionWatcher.Dispose();
}
int capacity = _sourceScalar != null?Utils.getCapacity(_sourceScalar) : Utils.getCapacity(_source);
_filteredPositions = new Positions <Position>(new List <Position>(_initialCapacity));
_itemInfos = new List <ItemInfo>(capacity);
_sourcePositions = new Positions <ItemInfo>(_itemInfos);
if (_rootSourceWrapper)
{
_sourceAsList.CollectionChanged -= _sourceNotifyCollectionChangedEventHandler;
}
else
{
_sourceAsList.CollectionChanged -= _sourceWeakNotifyCollectionChangedEventHandler.Handle;
_sourceWeakNotifyCollectionChangedEventHandler = null;
}
_sourceNotifyCollectionChangedEventHandler = null;
}
if (_sourceScalar != null)
{
_source = _sourceScalar.Value;
}
_sourceAsList = null;
if (_source != null)
{
if (_source is ObservableCollectionWithChangeMarker <TSourceItem> sourceAsList)
{
_sourceAsList = sourceAsList;
_rootSourceWrapper = false;
}
else
{
_sourceAsList = new RootSourceWrapper <TSourceItem>(_source);
_rootSourceWrapper = true;
}
_lastProcessedSourceChangeMarker = _sourceAsList.ChangeMarkerField;
Position nextItemPosition = _filteredPositions.Add();
int count = _sourceAsList.Count;
int insertingIndex = 0;
int sourceIndex;
for (sourceIndex = 0; sourceIndex < count; sourceIndex++)
{
TSourceItem sourceItem = _sourceAsList[sourceIndex];
Position currentFilteredItemPosition = null;
ItemInfo itemInfo = registerSourceItem(sourceItem, sourceIndex, null, null);
if (ApplyPredicate(sourceIndex))
{
if (originalCount > insertingIndex)
{
_items[insertingIndex++] = sourceItem;
}
else
{
_items.Insert(insertingIndex++, sourceItem);
}
currentFilteredItemPosition = nextItemPosition;
nextItemPosition = _filteredPositions.Add();
}
itemInfo.FilteredPosition = currentFilteredItemPosition;
itemInfo.NextFilteredItemPosition = nextItemPosition;
}
for (int index = originalCount - 1; index >= insertingIndex; index--)
{
_items.RemoveAt(index);
}
_sourceNotifyCollectionChangedEventHandler = handleSourceCollectionChanged;
if (_rootSourceWrapper)
{
_sourceAsList.CollectionChanged += _sourceNotifyCollectionChangedEventHandler;
}
else
{
_sourceWeakNotifyCollectionChangedEventHandler =
new WeakNotifyCollectionChangedEventHandler(_sourceNotifyCollectionChangedEventHandler);
_sourceAsList.CollectionChanged += _sourceWeakNotifyCollectionChangedEventHandler.Handle;
}
}
else
{
_items.Clear();
}
reset();
}
