/*
* Parse a word starting with an ALetter, Numeric or Katakana character.
* Advances the iterator and returns the word break property of the current
* character.
*/
static int
S_parse_word(const char *text, size_t len, lucy_StringIter *iter,
int state, Inversion *inversion) {
int wb = -1;
lucy_StringIter start = *iter;
S_iter_advance(text, iter);
lucy_StringIter end = *iter;
while (iter->byte_pos < len) {
wb = S_wb_lookup(text + iter->byte_pos);
switch (wb) {
case WB_ALetter:
case WB_Numeric:
if (state == WB_Katakana) { goto word_break; }
break;
case WB_Katakana:
if (state == WB_ALetter || state == WB_Numeric) {
goto word_break;
}
break;
case WB_ExtendNumLet:
break;
case WB_Extend_Format:
// keep state
wb = state;
break;
case WB_MidNumLet:
case WB_MidLetter:
case WB_MidNum:
if ((state == WB_ALetter && wb != WB_MidNum)
|| (state == WB_Numeric && wb != WB_MidLetter)) {
wb = S_skip_extend_format(text, len, iter);
if (wb == state) { break; }
}
goto word_break;
default:
goto word_break;
}
state = wb;
S_iter_advance(text, iter);
end = *iter;
}
Token *token;
word_break:
token = Token_new(text + start.byte_pos, end.byte_pos - start.byte_pos,
start.char_pos, end.char_pos, 1.0f, 1);
Inversion_Append(inversion, token);
return wb;
}
void
StandardTokenizer_tokenize_str(StandardTokenizer *self, const char *text,
size_t len, Inversion *inversion) {
if ((len >= 1 && (uint8_t)text[len - 1] >= 0xC0)
|| (len >= 2 && (uint8_t)text[len - 2] >= 0xE0)
|| (len >= 3 && (uint8_t)text[len - 3] >= 0xF0)) {
THROW(ERR, "Invalid UTF-8 sequence");
}
lucy_StringIter iter = { 0, 0 };
while (iter.byte_pos < len) {
int wb = S_wb_lookup(text + iter.byte_pos);
while (wb >= WB_ASingle && wb <= WB_ExtendNumLet) {
if (wb == WB_ASingle) {
wb = S_parse_single(text, len, &iter, inversion);
}
else {
wb = S_parse_word(text, len, &iter, wb, inversion);
}
if (iter.byte_pos >= len) return;
}
S_iter_advance(text, &iter);
}
}
/*
* Advances the iterator skipping over Extend and Format characters.
* Returns the word break property of the current character.
*/
static int
S_skip_extend_format(const char *text, size_t len, lucy_StringIter *iter) {
int wb = -1;
do {
S_iter_advance(text, iter);
if (iter->byte_pos >= len) { break; }
wb = S_wb_lookup(text + iter->byte_pos);
} while (wb == WB_Extend_Format);
return wb;
}
/*
* Parse a word starting with an ALetter, Numeric, Katakana, or ExtendNumLet
* character. Advances the iterator and returns the word break property of the
* current character.
*/
static int
S_parse_word(const char *text, size_t len, lucy_StringIter *iter,
int state, Inversion *inversion) {
int wb = -1;
lucy_StringIter start = *iter;
S_iter_advance(text, iter);
lucy_StringIter end = *iter;
while (iter->byte_pos < len) {
wb = S_wb_lookup(text + iter->byte_pos);
switch (wb) {
case WB_ALetter:
case WB_Hebrew_Letter:
case WB_Numeric:
if (state == WB_Katakana) { goto word_break; }
// Rules WB5, WB8, WB9, WB10, and WB13b.
break;
case WB_Katakana:
if (state != WB_Katakana && state != WB_ExtendNumLet) {
goto word_break;
}
// Rules WB13 and WB13b.
break;
case WB_ExtendNumLet:
// Rule WB13a.
break;
case WB_Extend_Format:
// Rule WB4. Keep state.
wb = state;
break;
case WB_Single_Quote:
case WB_MidNumLet:
case WB_MidLetter:
case WB_MidNum:
if (state == WB_ALetter) {
if (wb == WB_MidNum) { goto word_break; }
wb = S_skip_extend_format(text, len, iter);
if (wb == WB_ALetter || wb == WB_Hebrew_Letter) {
// Rules WB6 and WB7.
state = wb;
break;
}
}
else if (state == WB_Hebrew_Letter) {
if (wb == WB_MidNum) { goto word_break; }
if (wb == WB_Single_Quote) {
// Rule WB7a.
++end.byte_pos;
++end.char_pos;
}
wb = S_skip_extend_format(text, len, iter);
if (wb == WB_ALetter || wb == WB_Hebrew_Letter) {
// Rules WB6 and WB7.
state = wb;
break;
}
}
else if (state == WB_Numeric) {
if (wb == WB_MidLetter) { goto word_break; }
wb = S_skip_extend_format(text, len, iter);
if (wb == state) {
// Rules WB11 and WB12.
break;
}
}
goto word_break;
case WB_Double_Quote:
if (state == WB_Hebrew_Letter) {
wb = S_skip_extend_format(text, len, iter);
if (wb == state) {
// Rules WB7b and WB7c.
break;
}
}
goto word_break;
default:
goto word_break;
}
state = wb;
S_iter_advance(text, iter);
end = *iter;
}
Token *token;
word_break:
token = Token_new(text + start.byte_pos, end.byte_pos - start.byte_pos,
start.char_pos, end.char_pos, 1.0f, 1);
Inversion_Append(inversion, token);
return wb;
}
