private static DiffItem Next(DiffList diffList, int diffIndex)
{
if (diffIndex < diffList.Count)
{
return(diffList[diffIndex]);
}
return(null);
}
public static DiffList Compress(DiffList diffList)
{
DiffList result = new DiffList();
foreach (DiffItem diffItem in diffList)
{
if (diffItem.Status != DiffStatus.Unchanged)
{
result.Add(diffItem);
}
}
return(result);
}
public static System.IO.TextReader Patch(System.IO.TextReader source, DiffList diffList)
{
System.Collections.ArrayList sourceList = new System.Collections.ArrayList();
string line;
while ((line = source.ReadLine()) != null)
{
sourceList.Add(line);
}
System.Collections.ArrayList results = Patch(sourceList, diffList);
System.IO.MemoryStream memoryStream = new System.IO.MemoryStream();
System.IO.StreamWriter streamWriter = new System.IO.StreamWriter(memoryStream);
int i = 0;
foreach (string result in results)
{
if (i == (results.Count - 1))
{
streamWriter.Write(result);
}
else
{
streamWriter.WriteLine(result);
}
i++;
}
streamWriter.Flush();
memoryStream.Position = 0;
System.IO.StreamReader streamReader = new System.IO.StreamReader(memoryStream);
return(streamReader);
}
public static DiffList Diff(System.Collections.IList source, System.Collections.IList target)
{
DiffList results = new DiffList();
int i = 0;
int j = 0;
int k = 0;
while (!(i == source.Count && j == target.Count))
{
//End of target.
if (j == target.Count)
{
results.Add(new DiffItem(DiffStatus.Deleted, i, source[i]));
i++;
continue;
}
//End of source.
if (i == source.Count)
{
results.Add(new DiffItem(DiffStatus.Inserted, j, target[j]));
j++;
continue;
}
//End of source.
if ((i + k) == source.Count)
{
results.Add(new DiffItem(DiffStatus.Deleted, i, source[i]));
results.Add(new DiffItem(DiffStatus.Inserted, j, target[j]));
i++;
j++;
k = 0;
continue;
}
//End of target.
if ((j + k) == target.Count)
{
results.Add(new DiffItem(DiffStatus.Deleted, i, source[i]));
results.Add(new DiffItem(DiffStatus.Inserted, j, target[j]));
i++;
j++;
k = 0;
continue;
}
bool match_i = false;
bool match_j = false;
if (source[i + k].Equals(target[j]))
{
match_i = true;
}
if (source[i].Equals(target[j + k]))
{
match_j = true;
}
if (match_i && match_j)
{
results.Add(new DiffItem(DiffStatus.Unchanged, i, source[i]));
i++;
j++;
k = 0;
}
else if (match_i)
{
results.Add(new DiffItem(DiffStatus.Deleted, i, source[i]));
i++;
k = 0;
}
else if (match_j)
{
results.Add(new DiffItem(DiffStatus.Inserted, j, target[j]));
j++;
k = 0;
}
else
{
k++;
}
}
return(results);
}
public static System.Collections.ArrayList Patch(System.Collections.IList target, DiffList diffList)
{
System.Collections.ArrayList results = new System.Collections.ArrayList();
diffList = Differ.Compress(diffList);
int length = target.Count;
foreach (DiffItem item in diffList)
{
switch (item.Status)
{
case DiffStatus.Deleted:
{
length--;
break;
}
case DiffStatus.Inserted:
{
length++;
break;
}
}
}
int diffIndex = 0;
DiffItem diffItem = Next(diffList, diffIndex);
int targetLineNumber = 0;
int line = 0;
for (int i = 0; i < length; i++)
{
if (diffItem != null && diffItem.Position == targetLineNumber && diffItem.Status == DiffStatus.Deleted)
{
//Skip a target line.
targetLineNumber++;
diffIndex++;
diffItem = Next(diffList, diffIndex);
}
if (diffItem != null && diffItem.Position == line && diffItem.Status == DiffStatus.Inserted)
{
results.Add(diffItem.Value);
line++;
diffIndex++;
diffItem = Next(diffList, diffIndex);
continue;
}
results.Add(target[targetLineNumber]);
targetLineNumber++;
line++;
}
return(results);
}