DocumentChangedEventArgs ComputeChanges(ISassStylesheet previous, ISassStylesheet current, ITextSnapshot snapshot, SingleTextChange change)
{
if (previous == null)
return new DocumentChangedEventArgs { Stylesheet = current, ChangeStart = 0, ChangeEnd = snapshot.Length };
int start = 0;
int end = Math.Min(change.Position + change.InsertedLength, snapshot.Length);
// we need to scan both trees until we find where they start lining up again
var offset = change.InsertedLength + (-1 * change.DeletedLength);
var original = previous.Children.FindItemContainingPosition(change.Position - change.DeletedLength) ?? previous as Stylesheet;
var updated = current.Children.FindItemContainingPosition(change.Position + change.InsertedLength) ?? current as Stylesheet;
if (original != null && updated != null)
start = updated.Start;
while (true)
{
if (original == null || updated == null)
break;
// update our positions
start = Math.Min(start, updated.Start);
end = Math.Max(end, updated.End);
if (original.GetType() == updated.GetType())
{
// there are two types of changes (adding characters or removing characters)
// if we added characters then we'll need to adjust end characters
// if we deleted characters then we'll need to offset starting characters OR ending characters
// checking for length being extended by adding characters
if (original.Start == updated.Start && (original.End + change.InsertedLength) == updated.End)
{
end = updated.End;
break;
}
// checking for length being shortened by deleting characters
else if (original.Start == updated.Start && (original.End - change.DeletedLength) == updated.End)
{
break;
}
// checking for removal of nodes?
else if (original.Start == (updated.Start - change.DeletedLength) && (original.End - change.DeletedLength) == updated.End)
{
break;
}
}
original = original.InOrderSuccessor();
updated = updated.InOrderSuccessor();
}
return new DocumentChangedEventArgs
{
Stylesheet = current,
ChangeStart = Math.Min(start, change.Position),
ChangeEnd = Math.Max(end, change.Position + change.InsertedLength)
};
}
void Process(ITextSnapshot snapshot, SingleTextChange change)
{
var stylesheet = ParsingTask.Parse(new TextSnapshotParsingRequest(Buffer, Document));
if (stylesheet != null)
{
var previous = Document.Update(stylesheet);
var args = ComputeChanges(previous, stylesheet, snapshot, change);
OnDocumentChanged(args);
// update intellisense cache
if (Buffer.CurrentSnapshot == snapshot)
{
Task.Run(() => Cache.Update(stylesheet, new SnapshotTextProvider(snapshot)));
}
}
}
void Process(ITextSnapshot snapshot, SingleTextChange change)
{
var stylesheet = ParsingTask.Parse(new TextSnapshotParsingRequest(Buffer, Document));
if (stylesheet != null)
{
var previous = Document.Update(stylesheet);
var args = ComputeChanges(previous, stylesheet, snapshot, change);
OnDocumentChanged(args);
// update intellisense cache
if (Buffer.CurrentSnapshot == snapshot)
Task.Run(() => Cache.Update(stylesheet, new SnapshotTextProvider(snapshot)));
}
}
DocumentChangedEventArgs ComputeChanges(ISassStylesheet previous, ISassStylesheet current, ITextSnapshot snapshot, SingleTextChange change)
{
if (previous == null)
{
return new DocumentChangedEventArgs {
Stylesheet = current, ChangeStart = 0, ChangeEnd = snapshot.Length
}
}
;
int start = 0;
int end = Math.Min(change.Position + change.InsertedLength, snapshot.Length);
// we need to scan both trees until we find where they start lining up again
var offset = change.InsertedLength + (-1 * change.DeletedLength);
var original = previous.Children.FindItemContainingPosition(change.Position - change.DeletedLength) ?? previous as Stylesheet;
var updated = current.Children.FindItemContainingPosition(change.Position + change.InsertedLength) ?? current as Stylesheet;
if (original != null && updated != null)
{
start = updated.Start;
}
while (true)
{
if (original == null || updated == null)
{
break;
}
// update our positions
start = Math.Min(start, updated.Start);
end = Math.Max(end, updated.End);
if (original.GetType() == updated.GetType())
{
// there are two types of changes (adding characters or removing characters)
// if we added characters then we'll need to adjust end characters
// if we deleted characters then we'll need to offset starting characters OR ending characters
// checking for length being extended by adding characters
if (original.Start == updated.Start && (original.End + change.InsertedLength) == updated.End)
{
end = updated.End;
break;
}
// checking for length being shortened by deleting characters
else if (original.Start == updated.Start && (original.End - change.DeletedLength) == updated.End)
{
break;
}
// checking for removal of nodes?
else if (original.Start == (updated.Start - change.DeletedLength) && (original.End - change.DeletedLength) == updated.End)
{
break;
}
}
original = original.InOrderSuccessor();
updated = updated.InOrderSuccessor();
}
return(new DocumentChangedEventArgs
{
Stylesheet = current,
ChangeStart = Math.Min(start, change.Position),
ChangeEnd = Math.Max(end, change.Position + change.InsertedLength)
});
}
