private static IEnumerable <T> DescendantsCore <T, K>(IEnumerable <T> source, Func <T, K> keySelector, Func <T, K> parentKeySelector, Equality <K> equality, K startKey, bool descendantsOnly = false, int?levelsCount = null)
where T : class
where K : class
{
PwrList <T> list = new PwrList <T>();
PwrFrameListView <T> view = new PwrFrameListView <T>(list);
int priorCount = list.Count;
if (descendantsOnly)
{
list.AddRange(source.Where(t => equality(parentKeySelector(t), startKey)));
}
else if (startKey != null)
{
list.AddRange(source.Where(t => equality(keySelector(t), startKey)));
}
int takeCount = list.Count - priorCount;
for (int passCount = 1; (!levelsCount.HasValue || levelsCount.Value > passCount) && takeCount > 0; passCount++)
{
view.FrameOffset = priorCount;
view.FrameSize = takeCount;
priorCount = list.Count;
list.AddRange(source.Where(t1 => parentKeySelector(t1) != null && view.Any(t2 => equality(keySelector(t2), parentKeySelector(t1)))));
takeCount = list.Count - priorCount;
}
return(list.AsEnumerable());
}
private static IEnumerable <T> AscendantsCore <T, K>(IEnumerable <T> source, Func <T, K> keySelector, Func <T, K> parentKeySelector, Equality <K> equality, K startKey, bool ascendantsOnly = false, int?levelsCount = null)
where T : class
where K : class
{
PwrList <T> list = new PwrList <T>();
T item = source.SingleOrDefault(t => equality(keySelector(t), startKey));
if (item != null && ascendantsOnly)
{
K parentKey = parentKeySelector(item);
item = parentKey != null?source.SingleOrDefault(t => equality(keySelector(t), parentKey)) : null;
}
if (item != null)
{
list.Add(item);
}
for (int passCount = 1; (!levelsCount.HasValue || levelsCount.Value > passCount) && item != null; passCount++)
{
K parentKey = parentKeySelector(item);
item = parentKey != null?source.SingleOrDefault(t => equality(keySelector(t), parentKey)) : null;
if (item != null)
{
list.Add(item);
}
}
return(list.AsEnumerable());
}
public PwrList <T> DequeueRangeFront(int count)
{
if (count < 0 || count > _innerList.Count)
{
throw new ArgumentOutOfRangeException("count");
}
var list = new PwrList <T>(InnerList.Enumerate(0, count, false));
InnerList.RemoveRange(0, count);
return(list);
}
public PwrList <T> DequeueRangeBack(int count)
{
if (count < 0 || count > _innerList.Count)
{
throw new ArgumentOutOfRangeException("count");
}
var index = InnerList.Count - count;
var list = new PwrList <T>(InnerList.Enumerate(index, count, true));
InnerList.RemoveRange(index, count);
return(list);
}
public PwrList <T> DequeRangeBack(K key, int count)
{
if (count < 0 || count > InnerList.Count)
{
throw new ArgumentOutOfRangeException("count");
}
var list = new PwrList <T>(count);
var index = InnerList.BinarySearch(t => KeyComparison(KeySelector(t), key), SortingOption.Last);
while (index >= 0 && index < InnerList.Count && KeyComparison(KeySelector(InnerList[index]), key) == 0 && count-- > 0)
{
list.Add(InnerList[index]);
InnerList.RemoveAt(index--);
}
return(list);
}
public LookbackStream(Stream stream, int maxSize, bool leaveOpen)
{
_stream = stream;
_leaveOpen = leaveOpen;
_buffer = new PwrList <byte>(maxSize)
{
AutoTrim = false
};
_offset = _buffer.Count;
try
{
_position = _stream.Position;
}
catch (Exception)
{
_position = 0L;
}
}
public HierarchicalContext()
{
_innerList = new PwrList <T>();
_ancestors = new PwrListView <T>(_innerList);
}
public static IEnumerable <String> ReadLines(this TextReader reader, Func <IList <Char>, int> terminatorMatcher, Func <IList <Char>, string> terminatorConverter, int maxCount)
{
if (reader == null)
{
throw new ArgumentNullException("reader");
}
if (terminatorMatcher == null)
{
throw new ArgumentNullException("matchTerm");
}
if (maxCount < 0)
{
throw new ArgumentOutOfRangeException("maxCount");
}
if (maxCount == 0)
{
yield break;
}
int matched = 0;
var list = new PwrList <Char>();
var view = new PwrFrameListView <Char>(list);
var sb = new StringBuilder();
while (maxCount > 0)
{
int read = 0;
int accepted = 0;
while (true)
{
if (matched == list.Count)
{
if ((read = reader.Read()) < 0)
{
break;
}
else
{
list.PushLast((char)read);
}
}
view.FrameSize = matched + 1;
accepted = terminatorMatcher(view);
if (accepted > 0)
{
break;
}
else if (accepted == 0)
{
matched++;
}
else
{
matched = 0;
sb.Append(list.PopFirst());
}
}
if (accepted > matched + 1)
{
throw new InvalidOperationException("Accepted value is greater matched length.");
}
if (accepted > 0)
{
if (terminatorConverter == null)
{
sb.Append(list.GetRange(0, accepted).ToArray());
}
else
{
view.FrameSize = accepted;
string term = terminatorConverter(view);
if (!string.IsNullOrEmpty(term))
{
sb.Append(term);
}
}
yield return(sb.ToString());
sb.Clear();
list.RemoveRange(0, accepted);
matched = 0;
maxCount--;
}
if (read < 0)
{
break;
}
}
if (maxCount > 0)
{
if (list.Count > 0)
{
sb.AppendChars(list);
}
if (sb.Length > 0)
{
yield return(sb.ToString());
sb.Clear();
list.Clear();
}
}
}
