// isRightSideContext is true when linenumber corresponds to the right side (sha2).
// linenumber is one-based
private DiffContext createDiffContext(int linenumber, bool isRightSideContext, FullContextDiff context,
ContextDepth depth)
{
int startLineNumber = Math.Max(1, linenumber - depth.Up);
int endLineNumber = linenumber + depth.Down;
SparsedListIterator <string> itLeft = context.Left.Begin();
SparsedListIterator <string> itRight = context.Right.Begin();
if (isRightSideContext)
{
itRight = SparsedListUtils.FindNth(itRight, startLineNumber - 1);
itLeft = SparsedListUtils.Advance(itLeft, itRight.Position);
}
else
{
itLeft = SparsedListUtils.FindNth(itLeft, startLineNumber - 1);
itRight = SparsedListUtils.Advance(itRight, itLeft.Position);
}
DiffContext diffContext = new DiffContext
{
Lines = new List <DiffContext.Line>()
};
int iContextLine = 0;
while (true)
{
int?leftLineNumber = itLeft.LineNumber != null ? itLeft.LineNumber + 1 : null;
int?rightLineNumber = itRight.LineNumber != null ? itRight.LineNumber + 1 : null;
DiffContext.Line line = getLineContext(leftLineNumber, rightLineNumber, itLeft.Current, itRight.Current);
diffContext.Lines.Add(line);
if ((leftLineNumber.HasValue && !isRightSideContext && leftLineNumber == linenumber) ||
(rightLineNumber.HasValue && isRightSideContext && rightLineNumber == linenumber))
{
// zero-based index of a selected line in DiffContext.Lines
diffContext.SelectedIndex = iContextLine;
}
if ((leftLineNumber.HasValue && !isRightSideContext && leftLineNumber >= endLineNumber) ||
(rightLineNumber.HasValue && isRightSideContext && rightLineNumber >= endLineNumber))
{
// we've just reached a line that should not be included in the context
break;
}
if (!itLeft.Next() || !itRight.Next())
{
// we've just reached the end
break;
}
++iContextLine;
}
return(diffContext);
}
// linenumber is one-based
private static DiffContext.Line getContextLine(int linenumber, bool isRightSideContext, string text)
{
DiffContext.Line line = new DiffContext.Line
{
Text = text
};
DiffContext.Line.Side side = new DiffContext.Line.Side
{
Number = linenumber,
// this 'maker' cannot distinguish between modified and unmodified lines
State = DiffContext.Line.State.Changed
};
if (isRightSideContext)
{
line.Right = side;
}
else
{
line.Left = side;
}
return(line);
}
// leftLineNumber and rightLineNumber are one-based
private static DiffContext.Line getLineContext(int?leftLineNumber, int?rightLineNumber,
string leftLine, string rightLine)
{
DiffContext.Line line = new DiffContext.Line();
if (leftLineNumber.HasValue && rightLineNumber.HasValue)
{
Debug.Assert(leftLine == rightLine);
line.Left = getSide(leftLineNumber.Value, DiffContext.Line.State.Unchanged);
line.Right = getSide(rightLineNumber.Value, DiffContext.Line.State.Unchanged);
line.Text = leftLine;
}
else if (leftLineNumber.HasValue)
{
line.Left = getSide(leftLineNumber.Value, DiffContext.Line.State.Changed);
line.Text = leftLine;
}
else if (rightLineNumber.HasValue)
{
line.Right = getSide(rightLineNumber.Value, DiffContext.Line.State.Changed);
line.Text = rightLine;
}
else
{
Debug.Assert(false);
}
return(line);
}
private static string getCode(DiffContext.Line line)
{
if (line.Text.Length == 0)
{
return("<br");
}
// replace some special symbols such as '<' or '>'
string encodedText = System.Net.WebUtility.HtmlEncode(line.Text);
// replace spaces with  
return(encodedText
.Replace("\t", " ") /* replace each TAB with four spaces */
.Replace(" ", " ")); /* replace each SPACE with */
}
private string getDiffCellClass(DiffContext.Line line)
{
if (line.Left.HasValue && line.Right.HasValue)
{
return("unchanged");
}
else if (line.Left.HasValue)
{
return(line.Left.Value.State == DiffContext.Line.State.Unchanged ? "unchanged" : "removed");
}
else if (line.Right.HasValue)
{
return(line.Right.Value.State == DiffContext.Line.State.Unchanged ? "unchanged" : "added");
}
throw new ArgumentException(String.Format("Bad context line: {0}", line.ToString()));
}
private string getCode(DiffContext.Line line)
{
if (line.Text.Length == 0)
{
return("<br");
}
string trimmed = line.Text.TrimStart();
int leadingSpaces = line.Text.Length - trimmed.Length;
string spaces = string.Empty;
for (int i = 0; i < leadingSpaces; ++i)
{
spaces += " ";
}
return(spaces + System.Net.WebUtility.HtmlEncode(trimmed));
}
private string getCode(DiffContext.Line line)
{
if (line.Text.Length == 0)
{
return("<br");
}
string trimmed = line.Text.TrimStart();
int leadingSpaces = line.Text.Length - trimmed.Length;
StringBuilder result = new StringBuilder();
for (int i = 0; i < leadingSpaces; ++i)
{
result.Append(" ");
}
result.Append(System.Net.WebUtility.HtmlEncode(trimmed));
return(result.ToString());
}
private string getRightLineNumber(DiffContext.Line line)
{
return(line.Right?.Number.ToString() ?? "");
}
private static string getLeftLineNumber(DiffContext.Line line)
{
return(line.Left?.Number.ToString() ?? "");
}