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Refactor

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This commit is contained in:
F. Levi 2024-10-01 17:19:15 +03:00
parent eabc14c268
commit 6d16230f17
1 changed files with 158 additions and 169 deletions
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327
milli/src/search/new/matches/mod.rs
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@ -181,6 +181,149 @@ impl SimpleTokenKind {
}
}
#[derive(PartialEq, PartialOrd)]
struct MatchIntervalScore(i16, i16, i16);
impl MatchIntervalScore {
/// Compute the score of a match interval:
/// 1) count unique matches
/// 2) calculate distance between matches
/// 3) count ordered matches
fn new(matches: &[Match]) -> Self {
let mut ids: Vec<WordId> = Vec::with_capacity(matches.len());
let mut order_score = 0;
let mut distance_score = 0;
// count score for phrases
fn tally_phrase_scores(
fwp: &usize,
lwp: &usize,
order_score: &mut i16,
distance_score: &mut i16,
) {
let words_in_phrase_minus_one = (lwp - fwp) as i16;
// will always be ordered, so +1 for each space between words
*order_score += words_in_phrase_minus_one;
// distance will always be 1, so -1 for each space between words
*distance_score -= words_in_phrase_minus_one;
}
let mut iter = matches.iter().peekable();
while let Some(m) = iter.next() {
if let Some(next_match) = iter.peek() {
// if matches are ordered
if next_match.ids.iter().min() > m.ids.iter().min() {
order_score += 1;
}
let m_last_word_pos = match m.position {
MatchPosition::Word { word_position, .. } => word_position,
MatchPosition::Phrase { word_positions: (fwp, lwp), .. } => {
tally_phrase_scores(&fwp, &lwp, &mut order_score, &mut distance_score);
lwp
}
};
let next_match_first_word_pos = next_match.get_first_word_pos();
// compute distance between matches
distance_score -= (next_match_first_word_pos - m_last_word_pos).min(7) as i16;
} else if let MatchPosition::Phrase { word_positions: (fwp, lwp), .. } = m.position {
// in case last match is a phrase, count score for its words
tally_phrase_scores(&fwp, &lwp, &mut order_score, &mut distance_score);
}
ids.extend(m.ids.iter());
}
ids.sort_unstable();
ids.dedup();
let uniq_score = ids.len() as i16;
// rank by unique match count, then by distance between matches, then by ordered match count.
Self(uniq_score, distance_score, order_score)
}
}
struct MatchIntervalWithScore {
interval: (usize, usize),
score: MatchIntervalScore,
}
impl MatchIntervalWithScore {
/// Returns the matches interval where the score computed by match_interval_score is the best.
fn find_best_match_interval(matches: &[Match], crop_size: usize) -> &[Match] {
let matches_len = matches.len();
if matches_len <= 1 {
return matches;
}
// positions of the first and the last match of the best matches interval in `matches`.
let mut best_interval: Option<Self> = None;
let mut save_best_interval = |interval_first, interval_last, interval_score| {
let is_interval_score_better =
&best_interval.as_ref().map_or(true, |Self { score, .. }| interval_score > *score);
if *is_interval_score_better {
best_interval =
Some(Self { interval: (interval_first, interval_last), score: interval_score });
}
};
// we compute the matches interval if we have at least 2 matches.
// current interval positions.
let mut interval_first = 0;
let mut interval_first_match_first_word_pos = matches[interval_first].get_first_word_pos();
for (index, next_match) in matches.iter().enumerate() {
// if next match would make interval gross more than crop_size,
// we compare the current interval with the best one,
// then we increase `interval_first` until next match can be added.
let next_match_last_word_pos = next_match.get_last_word_pos();
// if the next match would mean that we pass the crop size window,
// we take the last valid match, that didn't pass this boundry, which is `index` - 1,
// and calculate a score for it, and check if it's better than our best so far
if next_match_last_word_pos - interval_first_match_first_word_pos >= crop_size {
// if index is 0 there is no last viable match
if index != 0 {
let interval_last = index - 1;
let interval_score =
MatchIntervalScore::new(&matches[interval_first..=interval_last]);
// keep interval if it's the best
save_best_interval(interval_first, interval_last, interval_score);
}
// advance start of the interval while interval is longer than crop_size.
loop {
interval_first += 1;
interval_first_match_first_word_pos =
matches[interval_first].get_first_word_pos();
if interval_first_match_first_word_pos > next_match_last_word_pos
|| next_match_last_word_pos - interval_first_match_first_word_pos
< crop_size
{
break;
}
}
}
}
// compute the last interval score and compare it to the best one.
let interval_last = matches_len - 1;
// if it's the last match with itself, we need to make sure it's
// not a phrase longer than the crop window
if interval_first != interval_last || matches[interval_first].get_word_count() < crop_size {
let interval_score = MatchIntervalScore::new(&matches[interval_first..=interval_last]);
save_best_interval(interval_first, interval_last, interval_score);
}
// if none of the matches fit the criteria above, default to the first one
let best_interval = best_interval.map_or((0, 0), |v| v.interval);
&matches[best_interval.0..=best_interval.1]
}
}
/// Structure used to analyze a string, compute words that match,
/// and format the source string, returning a highlighted and cropped sub-string.
pub struct Matcher<'t, 'tokenizer, 'b, 'lang> {
@ -415,14 +558,16 @@ impl<'t, 'tokenizer> Matcher<'t, 'tokenizer, '_, '_> {
(crop_byte_start, crop_byte_end)
} else {
// there's one match? and it's longer than the crop window, so we have to advance inward
// there's one match and it's longer than the crop window, so we have to advance inward
let mut remaining_extra_words = matches_window_len - crop_size;
let mut tokens_from_end =
tokens[..=last_match_last_token_position].iter().rev().peekable();
while remaining_extra_words > 0 {
let token_from_end_kind =
tokens_from_end.peek().map(SimpleTokenKind::get).expect("TODO");
let token_from_end_kind = tokens_from_end
.peek()
.map(SimpleTokenKind::get)
.expect("Expected iterator to not reach end");
if token_from_end_kind.is_not_separator() {
remaining_extra_words -= 1;
}
@ -435,165 +580,15 @@ impl<'t, 'tokenizer> Matcher<'t, 'tokenizer, '_, '_> {
} else {
&0
};
let crop_byte_end = tokens_from_end.next().map(|t| t.byte_start).expect("TODO");
let crop_byte_end = tokens_from_end
.next()
.map(|t| t.byte_start)
.expect("Expected iterator to not reach end");
(*crop_byte_start, crop_byte_end)
}
}
/// Compute the score of a match interval:
/// 1) count unique matches
/// 2) calculate distance between matches
/// 3) count ordered matches
fn match_interval_score(&self, matches: &[Match]) -> (i16, i16, i16) {
let mut ids: Vec<WordId> = Vec::with_capacity(matches.len());
let mut order_score = 0;
let mut distance_score = 0;
// count score for phrases
fn tally_phrase_scores(
fwp: &usize,
lwp: &usize,
order_score: &mut i16,
distance_score: &mut i16,
) {
let words_in_phrase_minus_one = (lwp - fwp) as i16;
// will always be ordered, so +1 for each space between words
*order_score += words_in_phrase_minus_one;
// distance will always be 1, so -1 for each space between words
*distance_score -= words_in_phrase_minus_one;
}
let mut iter = matches.iter().peekable();
while let Some(m) = iter.next() {
if let Some(next_match) = iter.peek() {
// if matches are ordered
if next_match.ids.iter().min() > m.ids.iter().min() {
order_score += 1;
}
let m_last_word_pos = match m.position {
MatchPosition::Word { word_position, .. } => word_position,
MatchPosition::Phrase { word_positions: (fwp, lwp), .. } => {
tally_phrase_scores(&fwp, &lwp, &mut order_score, &mut distance_score);
lwp
}
};
let next_match_first_word_pos = next_match.get_first_word_pos();
// compute distance between matches
distance_score -= (next_match_first_word_pos - m_last_word_pos).min(7) as i16;
} else if let MatchPosition::Phrase { word_positions: (fwp, lwp), .. } = m.position {
// in case last match is a phrase, count score for its words
tally_phrase_scores(&fwp, &lwp, &mut order_score, &mut distance_score);
}
ids.extend(m.ids.iter());
}
ids.sort_unstable();
ids.dedup();
let uniq_score = ids.len() as i16;
// rank by unique match count, then by distance between matches, then by ordered match count.
(uniq_score, distance_score, order_score)
}
/// Returns the matches interval where the score computed by match_interval_score is the best.
fn find_best_match_interval<'a>(&self, matches: &'a [Match], crop_size: usize) -> &'a [Match] {
let matches_len = matches.len();
if matches_len <= 1 {
return matches;
}
// positions of the first and the last match of the best matches interval in `matches`.
struct BestInterval {
interval: (usize, usize),
score: (i16, i16, i16),
}
fn save_best_interval(
best_interval: &mut Option<BestInterval>,
interval_first: usize,
interval_last: usize,
interval_score: (i16, i16, i16),
) {
if let Some(best_interval) = best_interval {
if interval_score > best_interval.score {
best_interval.interval = (interval_first, interval_last);
best_interval.score = interval_score;
}
} else {
*best_interval = Some(BestInterval {
interval: (interval_first, interval_last),
score: interval_score,
});
}
}
let mut best_interval: Option<BestInterval> = None;
// we compute the matches interval if we have at least 2 matches.
// current interval positions.
let mut interval_first = 0;
let mut interval_first_match_first_word_pos = matches[interval_first].get_first_word_pos();
for (index, next_match) in matches.iter().enumerate() {
// if next match would make interval gross more than crop_size,
// we compare the current interval with the best one,
// then we increase `interval_first` until next match can be added.
let next_match_last_word_pos = next_match.get_last_word_pos();
// if the next match would mean that we pass the crop size window,
// we take the last valid match, that didn't pass this boundry, which is `index` - 1,
// and calculate a score for it, and check if it's better than our best so far
if next_match_last_word_pos - interval_first_match_first_word_pos >= crop_size {
// if index is 0 there is no last viable match
if index != 0 {
let interval_last = index - 1;
let interval_score =
self.match_interval_score(&matches[interval_first..=interval_last]);
// keep interval if it's the best
save_best_interval(
&mut best_interval,
interval_first,
interval_last,
interval_score,
);
}
// advance start of the interval while interval is longer than crop_size.
loop {
interval_first += 1;
interval_first_match_first_word_pos =
matches[interval_first].get_first_word_pos();
if interval_first_match_first_word_pos > next_match_last_word_pos
|| next_match_last_word_pos - interval_first_match_first_word_pos
< crop_size
{
break;
}
}
}
}
// compute the last interval score and compare it to the best one.
let interval_last = matches_len - 1;
// if it's the last match with itself, we need to make sure it's
// not a phrase longer than the crop window
if interval_first != interval_last || matches[interval_first].get_word_count() < crop_size {
let interval_score =
self.match_interval_score(&matches[interval_first..=interval_last]);
save_best_interval(&mut best_interval, interval_first, interval_last, interval_score);
}
// if none of the matches fit the criteria above, default to the first one
let best_interval = best_interval.map_or((0, 0), |v| v.interval);
&matches[best_interval.0..=best_interval.1]
}
// Returns the formatted version of the original text.
pub fn format(&mut self, format_options: FormatOptions) -> Cow<'t, str> {
if !format_options.highlight && format_options.crop.is_none() {
@ -606,7 +601,9 @@ impl<'t, 'tokenizer> Matcher<'t, 'tokenizer, '_, '_> {
// crop around the best interval.
let (byte_start, byte_end) = match format_options.crop {
Some(crop_size) if crop_size > 0 => {
let matches = self.find_best_match_interval(matches, crop_size);
let matches = MatchIntervalWithScore::find_best_match_interval(
matches, crop_size,
);
self.crop_bounds(tokens, matches, crop_size)
}
_ => (0, self.text.len()),
@ -1046,6 +1043,7 @@ mod tests {
let mut matcher = builder.build(text, None);
insta::assert_snapshot!(
matcher.format(format_options),
// @TODO: Should probably highlight it all, even if it didn't fit the whole phrase
@"The groundbreaking invention had the power to split the world…"
);
@ -1057,6 +1055,7 @@ mod tests {
let mut matcher = builder.build(text, None);
insta::assert_snapshot!(
matcher.format(format_options),
// @TODO: Should probably include end of string in this case?
@"…between those who <em>embraced progress and those who resisted change</em>…"
);
@ -1090,17 +1089,7 @@ mod tests {
let mut matcher = builder.build(text, None);
insta::assert_snapshot!(
matcher.format(format_options),
@"…invention <em>had the power to split the world between those</em>…"
);
let builder = MatcherBuilder::new_test(
&rtxn,
&temp_index,
"\"The groundbreaking invention\" \"had the power to split the world between those\"",
);
let mut matcher = builder.build(text, None);
insta::assert_snapshot!(
matcher.format(format_options),
// @TODO: "invention" should be highlighted as well
@"…invention <em>had the power to split the world between those</em>…"
);
}