/// <summary>
/// Implements <see cref="Transliterator.HandleTransliterate(IReplaceable, TransliterationPosition, bool)"/>.
/// </summary>
protected override void HandleTransliterate(IReplaceable text,
TransliterationPosition offsets, bool isIncremental)
{
int maxLen = UCharacterName.Instance.MaxCharNameLength + 1; // allow for temporary trailing space
StringBuffer name = new StringBuffer(maxLen);
// Get the legal character set
UnicodeSet legal = new UnicodeSet();
UCharacterName.Instance.GetCharNameCharacters(legal);
int cursor = offsets.Start;
int limit = offsets.Limit;
// Modes:
// 0 - looking for open delimiter
// 1 - after open delimiter
int mode = 0;
int openPos = -1; // open delim candidate pos
int c;
while (cursor < limit)
{
c = text.Char32At(cursor);
switch (mode)
{
case 0: // looking for open delimiter
if (c == OPEN_DELIM)
{ // quick check first
openPos = cursor;
int i = Utility.ParsePattern(OPEN_PAT, text, cursor, limit);
if (i >= 0 && i < limit)
{
mode = 1;
name.Length = 0;
cursor = i;
continue; // *** reprocess char32At(cursor)
}
}
break;
case 1: // after open delimiter
// Look for legal chars. If \s+ is found, convert it
// to a single space. If closeDelimiter is found, exit
// the loop. If any other character is found, exit the
// loop. If the limit is reached, exit the loop.
// Convert \s+ => SPACE. This assumes there are no
// runs of >1 space characters in names.
if (PatternProps.IsWhiteSpace(c))
{
// Ignore leading whitespace
if (name.Length > 0 &&
name[name.Length - 1] != SPACE)
{
name.Append(SPACE);
// If we are too long then abort. maxLen includes
// temporary trailing space, so use '>'.
if (name.Length > maxLen)
{
mode = 0;
}
}
break;
}
if (c == CLOSE_DELIM)
{
int len = name.Length;
// Delete trailing space, if any
if (len > 0 &&
name[len - 1] == SPACE)
{
name.Length = --len;
}
c = UChar.GetCharFromExtendedName(name.ToString());
if (c != -1)
{
// Lookup succeeded
// assert(UTF16.getCharCount(CLOSE_DELIM) == 1);
cursor++; // advance over CLOSE_DELIM
string str = UTF16.ValueOf(c);
text.Replace(openPos, cursor, str);
// Adjust indices for the change in the length of
// the string. Do not assume that str.length() ==
// 1, in case of surrogates.
int delta = cursor - openPos - str.Length;
cursor -= delta;
limit -= delta;
// assert(cursor == openPos + str.length());
}
// If the lookup failed, we leave things as-is and
// still switch to mode 0 and continue.
mode = 0;
openPos = -1; // close off candidate
continue; // *** reprocess char32At(cursor)
}
if (legal.Contains(c))
{
UTF16.Append(name, c);
// If we go past the longest possible name then abort.
// maxLen includes temporary trailing space, so use '>='.
if (name.Length >= maxLen)
{
mode = 0;
}
}
// Invalid character
else
{
--cursor; // Backup and reprocess this character
mode = 0;
}
break;
}
cursor += UTF16.GetCharCount(c);
}
offsets.ContextLimit += limit - offsets.Limit;
offsets.Limit = limit;
// In incremental mode, only advance the cursor up to the last
// open delimiter candidate.
offsets.Start = (isIncremental && openPos >= 0) ? openPos : cursor;
}
