public TextLineList(TextData owner)
{
this.owner = owner;
}
public static TextData ApplyEdit(TextData previous, TextLocation start, TextLocation end, TextData replacement)
{
// Optimized for the vast majority of text edits -- an edit (single-line, typically single-character) on the active line
if (replacement.Lines.Count == 1 && start.Line == previous.ActiveLineIndex && end.Line == start.Line)
{
Debug.Assert(replacement.Lines[0].EndMarker == EndMarker.EOB);
string editedLineText = previous.activeLine.Text.Substring(0, start.Index) + replacement.lines[0].Text + previous.activeLine.Text.Substring(end.Index);
TextLine editedLine = new TextLine(editedLineText, previous.activeLine.EndMarker);
return(new TextData(previous.beforeBlock, editedLine, previous.afterBlock, previous.TextLength + editedLine.Length - previous.activeLine.Length));
}
// All other cases require reconstruction of the before/after blocks (in the current implementation -- more intelligent
// mechanisms could be built to increase memory reuse). This is still not terrible, as the untouched lines are reused; only the
// blocks (arrays of line references) are recreated.
// After this edit, we assume that the *end* of the inserted text is the active line.
int linesAdded = replacement.Lines.Count - 1;
int linesRemoved = end.Line - start.Line;
int totalLines = previous.Lines.Count + linesAdded - linesRemoved;
int beforeLines = start.Line + replacement.Lines.Count - 1;
int afterLines = totalLines - beforeLines - 1;
Debug.Assert(totalLines == beforeLines + afterLines + 1, "Miscalculation in line totals");
var before = new TextLine[beforeLines];
var after = new TextLine[afterLines];
TextLine newActiveLine;
string editLineText;
int newLength = 0;
// There are two cases -- the replacement is only one line (so we only end up creating one new TextLine), or it is more than one
// (so we end up creating 2 new TextLines). There are other opportunities for optimization in the latter (inserting at index 0, or
// the last line of the replacement being empty) to consider later.
if (replacement.Lines.Count == 1)
{
for (int i = 0; i < beforeLines; i++)
{
before[i] = previous.Lines[i];
newLength += before[i].LengthWithEndMarker;
}
editLineText = previous.Lines[start.Line].Text.Substring(0, start.Index) + replacement.Lines[0].Text + previous.Lines[end.Line].Text.Substring(end.Index);
newActiveLine = new TextLine(editLineText, previous.Lines[end.Line].EndMarker);
newLength += newActiveLine.LengthWithEndMarker;
for (int i = 0; i < afterLines; i++)
{
after[i] = previous.Lines[end.Line + i + 1];
newLength += after[i].LengthWithEndMarker;
}
}
else
{
for (int i = 0; i < start.Line; i++)
{
before[i] = previous.Lines[i];
newLength += before[i].LengthWithEndMarker;
}
editLineText = previous.Lines[start.Line].Text.Substring(0, start.Index) + replacement.Lines[0].Text;
before[start.Line] = new TextLine(editLineText, replacement.Lines[0].EndMarker);
newLength += before[start.Line].LengthWithEndMarker;
for (int i = 1; i < replacement.Lines.Count - 1; i++)
{
before[start.Line + i] = replacement.Lines[i];
newLength += before[start.Line + i].LengthWithEndMarker;
}
editLineText = replacement.Lines[replacement.Lines.Count - 1].Text + previous.Lines[end.Line].Text.Substring(end.Index);
newActiveLine = new TextLine(editLineText, previous.Lines[end.Line].EndMarker);
newLength += newActiveLine.LengthWithEndMarker;
for (int i = 0; i < afterLines; i++)
{
after[i] = previous.Lines[end.Line + i + 1];
newLength += after[i].LengthWithEndMarker;
}
}
return(new TextData(before, newActiveLine, after, newLength));
}
static TextData()
{
Empty = TextData.FromString(null);
}
public TextData GetSubrange(TextLocation start, TextLocation end)
{
return(TextData.FromString(this.ToString(start, end)));
}
public abstract bool Write(TextLocation start, TextLocation end, TextData replacement);
protected abstract List <TextFormatInfo> Parse(TextData textData, Func <bool> isCanceled);
public static TextBuffer FromText(string text, bool normalizeEndMarkers = false)
{
return(new TextBuffer(TextData.FromString(text, normalizeEndMarkers)));
}