internal static Position findBeginningOfFragment(IScintillaGateway scintillaGateway, Position start, Predicate <char> predicate)
{
for (int pos = start.Value; ; pos--)
{
if (pos == 0)
{
if (predicate((char)scintillaGateway.GetCharAt(new Position(0))))
{
return(new Position(0));
}
else
{
return(new Position(1));
}
}
if (!predicate((char)scintillaGateway.GetCharAt(new Position(pos))))
{
return(new Position(pos + 1));
}
}
}
internal static Tuple <string, Position, Position> extractHexFromCurrentPosition(IScintillaGateway scintillaGateway)
{
Position position = scintillaGateway.GetCurrentPos();
int ch = scintillaGateway.GetCharAt(position);
if (!isValidHex((char)ch))
{
MessageBox.Show("invalid hex character under cursor");
return(null);
}
// scan backward
Position positionOfHex = findBeginningOfFragment(scintillaGateway, position, isValidHex);
// get hex from known start position until last valid character
return(getFragmentStartingFrom(scintillaGateway, positionOfHex.Value, isValidHex));
}
internal static Tuple <string, Position, Position> extractBase64FromCurrentPosition(IScintillaGateway scintillaGateway)
{
int max = scintillaGateway.GetLength();
Position position = scintillaGateway.GetCurrentPos();
int ch = scintillaGateway.GetCharAt(position);
if (!isValidBase64Character((char)ch))
{
MessageBox.Show("invalid base64 character under cursor");
return(null);
}
// scan backward
Position positionOfBase64 = findBeginningOfFragment(scintillaGateway, position, isValidBase64Character);
// get base64 from known start position until last valid character
return(getFragmentStartingFrom(scintillaGateway, positionOfBase64.Value, isValidBase64Character));
}
internal static Tuple <string, Position, Position> getFragmentStartingFrom(IScintillaGateway scintillaGateway, int start, Predicate <char> predicate)
{
int length = scintillaGateway.GetLength();
int lastValid = start;
List <char> chars = new List <char>();
for (int pos = start; pos < length; pos++)
{
int ch = scintillaGateway.GetCharAt(new Position(pos));
if (predicate((char)ch))
{
chars.Add((char)ch);
lastValid = pos;
}
else
{
break;
}
}
return(new Tuple <string, Position, Position>(new string(chars.ToArray()), new Position(start), new Position(lastValid + 1)));
}
