/// <summary>The subSpans are ordered in the same doc, so there is a possible match.
/// Compute the slop while making the match as short as possible by advancing
/// all subSpans except the last one in reverse order.
/// </summary>
private bool ShrinkToAfterShortestMatch()
{
matchStart = subSpans[subSpans.Length - 1].Start();
matchEnd = subSpans[subSpans.Length - 1].End();
System.Collections.Generic.Dictionary <byte[], byte[]> possibleMatchPayloads = new System.Collections.Generic.Dictionary <byte[], byte[]>();
if (subSpans[subSpans.Length - 1].IsPayloadAvailable())
{
System.Collections.Generic.ICollection <byte[]> payload = subSpans[subSpans.Length - 1].GetPayload();
foreach (byte[] pl in payload)
{
if (!possibleMatchPayloads.ContainsKey(pl))
{
possibleMatchPayloads.Add(pl, pl);
}
}
}
System.Collections.Generic.List <byte[]> possiblePayload = null;
int matchSlop = 0;
int lastStart = matchStart;
int lastEnd = matchEnd;
for (int i = subSpans.Length - 2; i >= 0; i--)
{
Spans prevSpans = subSpans[i];
if (collectPayloads && prevSpans.IsPayloadAvailable())
{
System.Collections.Generic.ICollection <byte[]> payload = prevSpans.GetPayload();
possiblePayload = new System.Collections.Generic.List <byte[]>(payload.Count);
possiblePayload.AddRange(payload);
}
int prevStart = prevSpans.Start();
int prevEnd = prevSpans.End();
while (true)
{
// Advance prevSpans until after (lastStart, lastEnd)
if (!prevSpans.Next())
{
inSameDoc = false;
more = false;
break; // Check remaining subSpans for final match.
}
else if (matchDoc != prevSpans.Doc())
{
inSameDoc = false; // The last subSpans is not advanced here.
break; // Check remaining subSpans for last match in this document.
}
else
{
int ppStart = prevSpans.Start();
int ppEnd = prevSpans.End(); // Cannot avoid invoking .end()
if (!DocSpansOrdered(ppStart, ppEnd, lastStart, lastEnd))
{
break; // Check remaining subSpans.
}
else
{
// prevSpans still before (lastStart, lastEnd)
prevStart = ppStart;
prevEnd = ppEnd;
if (collectPayloads && prevSpans.IsPayloadAvailable())
{
System.Collections.Generic.ICollection <byte[]> payload = prevSpans.GetPayload();
possiblePayload = new System.Collections.Generic.List <byte[]>(payload.Count);
possiblePayload.AddRange(payload);
}
}
}
}
if (collectPayloads && possiblePayload != null)
{
foreach (byte[] pl in possiblePayload)
{
if (!possibleMatchPayloads.ContainsKey(pl))
{
possibleMatchPayloads.Add(pl, pl);
}
}
}
System.Diagnostics.Debug.Assert(prevStart <= matchStart);
if (matchStart > prevEnd)
{
// Only non overlapping spans add to slop.
matchSlop += (matchStart - prevEnd);
}
/* Do not break on (matchSlop > allowedSlop) here to make sure
* that subSpans[0] is advanced after the match, if any.
*/
matchStart = prevStart;
lastStart = prevStart;
lastEnd = prevEnd;
}
bool match = matchSlop <= allowedSlop;
if (collectPayloads && match && possibleMatchPayloads.Count > 0)
{
matchPayload.AddRange(possibleMatchPayloads.Keys);
}
return(match); // ordered and allowed slop
}
public override int End()
{
return(spans.End());
}
/// <summary>Check whether two Spans in the same document are ordered.</summary>
/// <param name="spans1">
/// </param>
/// <param name="spans2">
/// </param>
/// <returns> true iff spans1 starts before spans2
/// or the spans start at the same position,
/// and spans1 ends before spans2.
/// </returns>
internal static bool DocSpansOrdered(Spans spans1, Spans spans2)
{
System.Diagnostics.Debug.Assert(spans1.Doc() == spans2.Doc(), "doc1 " + spans1.Doc() + " != doc2 " + spans2.Doc());
int start1 = spans1.Start();
int start2 = spans2.Start();
/* Do not call docSpansOrdered(int,int,int,int) to avoid invoking .end() : */
return (start1 == start2)?(spans1.End() < spans2.End()):(start1 < start2);
}