/// <summary>
/// Process atom labels from extended SMILES in a char iter.
/// </summary>
/// <param name="iter">char iteration</param>
/// <param name="dest">destination of labels (atomidx->label)</param>
/// <returns>parse success/failure</returns>
private static bool ProcessAtomLabels(CharIter iter, SortedDictionary <int, string> dest)
{
int atomIdx = 0;
while (iter.HasNext())
{
// fast forward through empty labels
while (iter.NextIf(';'))
{
atomIdx++;
}
char c = iter.Next();
if (c == '$')
{
iter.NextIf(','); // optional
// end of atom label
return(true);
}
else
{
iter.pos--; // push back
var beg = iter.pos;
var rollback = beg;
while (iter.HasNext())
{
if (iter.pos == beg && iter.Curr() == '_' && iter.Peek() == 'R')
{
++beg;
}
// correct step over of escaped label
if (iter.Curr() == '&')
{
rollback = iter.pos;
if (iter.NextIf('&') && iter.NextIf('#') && iter.NextIfDigit())
{
while (iter.NextIfDigit())
{
} // more digits
if (!iter.NextIf(';'))
{
iter.pos = rollback;
}
else
{
}
}
else
{
iter.pos = rollback;
}
}
else if (iter.Curr() == ';')
{
break;
}
else if (iter.Curr() == '$')
{
break;
}
else
{
iter.Next();
}
}
dest.Add(atomIdx, Unescape(iter.Substr(beg, iter.pos)));
atomIdx++;
if (iter.NextIf('$'))
{
iter.NextIf(','); // optional
return(true);
}
if (!iter.NextIf(';'))
{
return(false);
}
}
}
return(false);
}
