public DifferenceState GetByIndex(int index)
{
DifferenceState retval = _array[index];
if (retval == null)
{
retval = new DifferenceState();
_array[index] = retval;
}
return(retval);
}
private void GetLongestSourceMatch(DifferenceState curItem, int destIndex, int destEnd, int sourceStart, int sourceEnd)
{
int maxDestLength = (destEnd - destIndex) + 1;
int currentBestLength = 0;
int currentBestIndex = -1;
for (int sourceIndex = sourceStart; sourceIndex <= sourceEnd; sourceIndex++)
{
int maxLength = Math.Min(maxDestLength, (sourceEnd - sourceIndex) + 1);
if (maxLength <= currentBestLength)
{
// No chance to find a longer one any more
break;
}
int currentLength = GetSourceMatchLength(destIndex, sourceIndex, maxLength);
if (currentLength > currentBestLength)
{
// This is the best match so far
currentBestIndex = sourceIndex;
currentBestLength = currentLength;
}
// Jump over the match
sourceIndex += currentBestLength;
}
// DifferenceState current = _stateList.GetByIndex(destIndex);
if (currentBestIndex == -1)
{
curItem.SetNoMatch();
}
else
{
curItem.SetMatch(currentBestIndex, currentBestLength);
}
}
public DifferenceState GetByIndex(int index)
{
DifferenceState retval = _array[index];
if (retval == null)
{
retval = new DifferenceState();
_array[index] = retval;
}
return retval;
}
private void ProcessRange(int destStart, int destEnd, int sourceStart, int sourceEnd)
{
int curBestIndex = -1;
int curBestLength = -1;
DifferenceState curItem;
DifferenceState bestItem = null;
for (int destIndex = destStart; destIndex <= destEnd; destIndex++)
{
int maxPossibleDestLength = (destEnd - destIndex) + 1;
if (maxPossibleDestLength <= curBestLength)
{
// we won't find a longer one even if we looked
break;
}
curItem = _stateList.GetByIndex(destIndex);
if (!curItem.HasValidLength(sourceStart, sourceEnd, maxPossibleDestLength))
{
// recalc new best length since it isn't valid or has never been done.
GetLongestSourceMatch(curItem, destIndex, destEnd, sourceStart, sourceEnd);
}
if (curItem.Status == DifferenceStatus.Matched)
{
switch (_level)
{
case DifferenceEngineLevel.FastImperfect:
if (curItem.Length > curBestLength)
{
// this is longest match so far
curBestIndex = destIndex;
curBestLength = curItem.Length;
bestItem = curItem;
}
// Jump over the match
destIndex += curItem.Length - 1;
break;
case DifferenceEngineLevel.Medium:
if (curItem.Length > curBestLength)
{
// this is longest match so far
curBestIndex = destIndex;
curBestLength = curItem.Length;
bestItem = curItem;
// Jump over the match
destIndex += curItem.Length - 1;
}
break;
default:
if (curItem.Length > curBestLength)
{
// this is longest match so far
curBestIndex = destIndex;
curBestLength = curItem.Length;
bestItem = curItem;
}
break;
}
}
}
if (curBestIndex < 0)
{
// we are done - there are no matches in this span
}
else
{
if (bestItem != null)
{
int sourceIndex = bestItem.StartIndex;
_matchList.Add(DifferenceResultSpan.CreateNoChange(curBestIndex, sourceIndex, curBestLength));
if (destStart < curBestIndex)
{
// Still have more lower destination data
if (sourceStart < sourceIndex)
{
// Still have more lower source data
// Recursive call to process lower indexes
ProcessRange(destStart, curBestIndex - 1, sourceStart, sourceIndex - 1);
}
}
int upperDestStart = curBestIndex + curBestLength;
int upperSourceStart = sourceIndex + curBestLength;
if (destEnd > upperDestStart)
{
// we still have more upper dest data
if (sourceEnd > upperSourceStart)
{
// set still have more upper source data
// Recursive call to process upper indexes
ProcessRange(upperDestStart, destEnd, upperSourceStart, sourceEnd);
}
}
}
}
}
private void GetLongestSourceMatch(DifferenceState curItem, int destIndex, int destEnd, int sourceStart, int sourceEnd)
{
int maxDestLength = (destEnd - destIndex) + 1;
int currentBestLength = 0;
int currentBestIndex = -1;
for (int sourceIndex = sourceStart; sourceIndex <= sourceEnd; sourceIndex++)
{
int maxLength = Math.Min(maxDestLength, (sourceEnd - sourceIndex) + 1);
if (maxLength <= currentBestLength)
{
// No chance to find a longer one any more
break;
}
int currentLength = GetSourceMatchLength(destIndex, sourceIndex, maxLength);
if (currentLength > currentBestLength)
{
// This is the best match so far
currentBestIndex = sourceIndex;
currentBestLength = currentLength;
}
// Jump over the match
sourceIndex += currentBestLength;
}
// DifferenceState current = _stateList.GetByIndex(destIndex);
if (currentBestIndex == -1)
{
curItem.SetNoMatch();
}
else
{
curItem.SetMatch(currentBestIndex, currentBestLength);
}
}