anchor.rs

  1use crate::rope::TextDimension;
  2
  3use super::{Buffer, Content, FromAnchor, FullOffset, Point, ToOffset};
  4use anyhow::Result;
  5use std::{
  6    cmp::Ordering,
  7    fmt::{Debug, Formatter},
  8    ops::Range,
  9};
 10use sum_tree::{Bias, SumTree};
 11
 12#[derive(Clone, Eq, PartialEq, Debug, Hash)]
 13pub struct Anchor {
 14    pub full_offset: FullOffset,
 15    pub bias: Bias,
 16    pub version: clock::Global,
 17}
 18
 19#[derive(Clone)]
 20pub struct AnchorMap<T> {
 21    pub(crate) version: clock::Global,
 22    pub(crate) bias: Bias,
 23    pub(crate) entries: Vec<(FullOffset, T)>,
 24}
 25
 26#[derive(Clone)]
 27pub struct AnchorSet(pub(crate) AnchorMap<()>);
 28
 29#[derive(Clone)]
 30pub struct AnchorRangeMap<T> {
 31    pub(crate) version: clock::Global,
 32    pub(crate) entries: Vec<(Range<FullOffset>, T)>,
 33    pub(crate) start_bias: Bias,
 34    pub(crate) end_bias: Bias,
 35}
 36
 37#[derive(Clone)]
 38pub struct AnchorRangeSet(pub(crate) AnchorRangeMap<()>);
 39
 40#[derive(Clone)]
 41pub struct AnchorRangeMultimap<T: Clone> {
 42    pub(crate) entries: SumTree<AnchorRangeMultimapEntry<T>>,
 43    pub(crate) version: clock::Global,
 44    pub(crate) start_bias: Bias,
 45    pub(crate) end_bias: Bias,
 46}
 47
 48#[derive(Clone)]
 49pub(crate) struct AnchorRangeMultimapEntry<T> {
 50    pub(crate) range: FullOffsetRange,
 51    pub(crate) value: T,
 52}
 53
 54#[derive(Clone, Debug)]
 55pub(crate) struct FullOffsetRange {
 56    pub(crate) start: FullOffset,
 57    pub(crate) end: FullOffset,
 58}
 59
 60#[derive(Clone, Debug)]
 61pub(crate) struct AnchorRangeMultimapSummary {
 62    start: FullOffset,
 63    end: FullOffset,
 64    min_start: FullOffset,
 65    max_end: FullOffset,
 66    count: usize,
 67}
 68
 69impl Anchor {
 70    pub fn min() -> Self {
 71        Self {
 72            full_offset: FullOffset(0),
 73            bias: Bias::Left,
 74            version: Default::default(),
 75        }
 76    }
 77
 78    pub fn max() -> Self {
 79        Self {
 80            full_offset: FullOffset::MAX,
 81            bias: Bias::Right,
 82            version: Default::default(),
 83        }
 84    }
 85
 86    pub fn cmp<'a>(&self, other: &Anchor, buffer: impl Into<Content<'a>>) -> Result<Ordering> {
 87        let buffer = buffer.into();
 88
 89        if self == other {
 90            return Ok(Ordering::Equal);
 91        }
 92
 93        let offset_comparison = if self.version == other.version {
 94            self.full_offset.cmp(&other.full_offset)
 95        } else {
 96            buffer
 97                .full_offset_for_anchor(self)
 98                .cmp(&buffer.full_offset_for_anchor(other))
 99        };
100
101        Ok(offset_comparison.then_with(|| self.bias.cmp(&other.bias)))
102    }
103
104    pub fn bias_left(&self, buffer: &Buffer) -> Anchor {
105        if self.bias == Bias::Left {
106            self.clone()
107        } else {
108            buffer.anchor_before(self)
109        }
110    }
111
112    pub fn bias_right(&self, buffer: &Buffer) -> Anchor {
113        if self.bias == Bias::Right {
114            self.clone()
115        } else {
116            buffer.anchor_after(self)
117        }
118    }
119
120    pub fn summary<'a, D, C>(&self, content: C) -> D
121    where
122        D: TextDimension<'a>,
123        C: Into<Content<'a>>,
124    {
125        content.into().summary_for_anchor(self)
126    }
127}
128
129impl<T> AnchorMap<T> {
130    pub fn version(&self) -> &clock::Global {
131        &self.version
132    }
133
134    pub fn len(&self) -> usize {
135        self.entries.len()
136    }
137
138    pub fn iter<'a, D, C>(&'a self, content: C) -> impl Iterator<Item = (D, &'a T)> + 'a
139    where
140        D: 'a + TextDimension<'a>,
141        C: 'a + Into<Content<'a>>,
142    {
143        let content = content.into();
144        content
145            .summaries_for_anchors(
146                self.version.clone(),
147                self.bias,
148                self.entries.iter().map(|e| &e.0),
149            )
150            .zip(self.entries.iter().map(|e| &e.1))
151    }
152}
153
154impl AnchorSet {
155    pub fn version(&self) -> &clock::Global {
156        &self.0.version
157    }
158
159    pub fn len(&self) -> usize {
160        self.0.len()
161    }
162
163    pub fn iter<'a, D, C>(&'a self, content: C) -> impl Iterator<Item = D> + 'a
164    where
165        D: 'a + TextDimension<'a>,
166        C: 'a + Into<Content<'a>>,
167    {
168        self.0.iter(content).map(|(position, _)| position)
169    }
170}
171
172impl<T> AnchorRangeMap<T> {
173    pub fn version(&self) -> &clock::Global {
174        &self.version
175    }
176
177    pub fn len(&self) -> usize {
178        self.entries.len()
179    }
180
181    pub fn from_full_offset_ranges(
182        version: clock::Global,
183        start_bias: Bias,
184        end_bias: Bias,
185        entries: Vec<(Range<FullOffset>, T)>,
186    ) -> Self {
187        Self {
188            version,
189            start_bias,
190            end_bias,
191            entries,
192        }
193    }
194
195    pub fn ranges<'a, D>(
196        &'a self,
197        content: impl Into<Content<'a>> + 'a,
198    ) -> impl Iterator<Item = (Range<D>, &'a T)> + 'a
199    where
200        D: 'a + TextDimension<'a>,
201    {
202        let content = content.into();
203        content
204            .summaries_for_anchor_ranges(
205                self.version.clone(),
206                self.start_bias,
207                self.end_bias,
208                self.entries.iter().map(|e| &e.0),
209            )
210            .zip(self.entries.iter().map(|e| &e.1))
211    }
212
213    pub fn intersecting_ranges<'a, D, I>(
214        &'a self,
215        range: Range<(I, Bias)>,
216        content: impl Into<Content<'a>> + 'a,
217    ) -> impl Iterator<Item = (Range<D>, &'a T)> + 'a
218    where
219        D: 'a + TextDimension<'a>,
220        I: ToOffset,
221    {
222        let content = content.into();
223        let range = content.anchor_at(range.start.0, range.start.1)
224            ..content.anchor_at(range.end.0, range.end.1);
225
226        let mut probe_anchor = Anchor {
227            full_offset: Default::default(),
228            bias: self.start_bias,
229            version: self.version.clone(),
230        };
231        let start_ix = self.entries.binary_search_by(|probe| {
232            probe_anchor.full_offset = probe.0.end;
233            probe_anchor.cmp(&range.start, &content).unwrap()
234        });
235
236        match start_ix {
237            Ok(start_ix) | Err(start_ix) => content
238                .summaries_for_anchor_ranges(
239                    self.version.clone(),
240                    self.start_bias,
241                    self.end_bias,
242                    self.entries[start_ix..].iter().map(|e| &e.0),
243                )
244                .zip(self.entries.iter().map(|e| &e.1)),
245        }
246    }
247
248    pub fn full_offset_ranges(&self) -> impl Iterator<Item = &(Range<FullOffset>, T)> {
249        self.entries.iter()
250    }
251
252    pub fn min_by_key<'a, C, D, F, K>(
253        &self,
254        content: C,
255        mut extract_key: F,
256    ) -> Option<(Range<D>, &T)>
257    where
258        C: Into<Content<'a>>,
259        D: 'a + TextDimension<'a>,
260        F: FnMut(&T) -> K,
261        K: Ord,
262    {
263        let content = content.into();
264        self.entries
265            .iter()
266            .min_by_key(|(_, value)| extract_key(value))
267            .map(|(range, value)| (self.resolve_range(range, &content), value))
268    }
269
270    pub fn max_by_key<'a, C, D, F, K>(
271        &self,
272        content: C,
273        mut extract_key: F,
274    ) -> Option<(Range<D>, &T)>
275    where
276        C: Into<Content<'a>>,
277        D: 'a + TextDimension<'a>,
278        F: FnMut(&T) -> K,
279        K: Ord,
280    {
281        let content = content.into();
282        self.entries
283            .iter()
284            .max_by_key(|(_, value)| extract_key(value))
285            .map(|(range, value)| (self.resolve_range(range, &content), value))
286    }
287
288    fn resolve_range<'a, D>(&self, range: &Range<FullOffset>, content: &Content<'a>) -> Range<D>
289    where
290        D: 'a + TextDimension<'a>,
291    {
292        let mut anchor = Anchor {
293            full_offset: range.start,
294            bias: self.start_bias,
295            version: self.version.clone(),
296        };
297        let start = content.summary_for_anchor(&anchor);
298
299        anchor.full_offset = range.end;
300        anchor.bias = self.end_bias;
301        let end = content.summary_for_anchor(&anchor);
302
303        start..end
304    }
305}
306
307impl<T: PartialEq> PartialEq for AnchorRangeMap<T> {
308    fn eq(&self, other: &Self) -> bool {
309        self.version == other.version && self.entries == other.entries
310    }
311}
312
313impl<T: Eq> Eq for AnchorRangeMap<T> {}
314
315impl<T: Debug> Debug for AnchorRangeMap<T> {
316    fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), std::fmt::Error> {
317        let mut f = f.debug_map();
318        for (range, value) in &self.entries {
319            f.key(range);
320            f.value(value);
321        }
322        f.finish()
323    }
324}
325
326impl Debug for AnchorRangeSet {
327    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
328        let mut f = f.debug_set();
329        for (range, _) in &self.0.entries {
330            f.entry(range);
331        }
332        f.finish()
333    }
334}
335
336impl AnchorRangeSet {
337    pub fn len(&self) -> usize {
338        self.0.len()
339    }
340
341    pub fn version(&self) -> &clock::Global {
342        self.0.version()
343    }
344
345    pub fn ranges<'a, D, C>(&'a self, content: C) -> impl 'a + Iterator<Item = Range<Point>>
346    where
347        D: 'a + TextDimension<'a>,
348        C: 'a + Into<Content<'a>>,
349    {
350        self.0.ranges(content).map(|(range, _)| range)
351    }
352}
353
354impl<T: Clone> Default for AnchorRangeMultimap<T> {
355    fn default() -> Self {
356        Self {
357            entries: Default::default(),
358            version: Default::default(),
359            start_bias: Bias::Left,
360            end_bias: Bias::Left,
361        }
362    }
363}
364
365impl<T: Clone> AnchorRangeMultimap<T> {
366    pub fn version(&self) -> &clock::Global {
367        &self.version
368    }
369
370    pub fn intersecting_ranges<'a, I, O>(
371        &'a self,
372        range: Range<I>,
373        content: Content<'a>,
374        inclusive: bool,
375    ) -> impl Iterator<Item = (usize, Range<O>, &T)> + 'a
376    where
377        I: ToOffset,
378        O: FromAnchor,
379    {
380        let end_bias = if inclusive { Bias::Right } else { Bias::Left };
381        let range = range.start.to_full_offset(&content, Bias::Left)
382            ..range.end.to_full_offset(&content, end_bias);
383        let mut cursor = self.entries.filter::<_, usize>(
384            {
385                let content = content.clone();
386                let mut endpoint = Anchor {
387                    full_offset: FullOffset(0),
388                    bias: Bias::Right,
389                    version: self.version.clone(),
390                };
391                move |summary: &AnchorRangeMultimapSummary| {
392                    endpoint.full_offset = summary.max_end;
393                    endpoint.bias = self.end_bias;
394                    let max_end = endpoint.to_full_offset(&content, self.end_bias);
395                    let start_cmp = range.start.cmp(&max_end);
396
397                    endpoint.full_offset = summary.min_start;
398                    endpoint.bias = self.start_bias;
399                    let min_start = endpoint.to_full_offset(&content, self.start_bias);
400                    let end_cmp = range.end.cmp(&min_start);
401
402                    if inclusive {
403                        start_cmp <= Ordering::Equal && end_cmp >= Ordering::Equal
404                    } else {
405                        start_cmp == Ordering::Less && end_cmp == Ordering::Greater
406                    }
407                }
408            },
409            &(),
410        );
411
412        std::iter::from_fn({
413            let mut endpoint = Anchor {
414                full_offset: FullOffset(0),
415                bias: Bias::Left,
416                version: self.version.clone(),
417            };
418            move || {
419                if let Some(item) = cursor.item() {
420                    let ix = *cursor.start();
421                    endpoint.full_offset = item.range.start;
422                    endpoint.bias = self.start_bias;
423                    let start = O::from_anchor(&endpoint, &content);
424                    endpoint.full_offset = item.range.end;
425                    endpoint.bias = self.end_bias;
426                    let end = O::from_anchor(&endpoint, &content);
427                    let value = &item.value;
428                    cursor.next(&());
429                    Some((ix, start..end, value))
430                } else {
431                    None
432                }
433            }
434        })
435    }
436
437    pub fn from_full_offset_ranges(
438        version: clock::Global,
439        start_bias: Bias,
440        end_bias: Bias,
441        entries: impl Iterator<Item = (Range<FullOffset>, T)>,
442    ) -> Self {
443        Self {
444            version,
445            start_bias,
446            end_bias,
447            entries: SumTree::from_iter(
448                entries.map(|(range, value)| AnchorRangeMultimapEntry {
449                    range: FullOffsetRange {
450                        start: range.start,
451                        end: range.end,
452                    },
453                    value,
454                }),
455                &(),
456            ),
457        }
458    }
459
460    pub fn full_offset_ranges(&self) -> impl Iterator<Item = (Range<FullOffset>, &T)> {
461        self.entries
462            .cursor::<()>()
463            .map(|entry| (entry.range.start..entry.range.end, &entry.value))
464    }
465
466    pub fn filter<'a, O, F>(
467        &'a self,
468        content: Content<'a>,
469        mut f: F,
470    ) -> impl 'a + Iterator<Item = (usize, Range<O>, &T)>
471    where
472        O: FromAnchor,
473        F: 'a + FnMut(&'a T) -> bool,
474    {
475        let mut endpoint = Anchor {
476            full_offset: FullOffset(0),
477            bias: Bias::Left,
478            version: self.version.clone(),
479        };
480        self.entries
481            .cursor::<()>()
482            .enumerate()
483            .filter_map(move |(ix, entry)| {
484                if f(&entry.value) {
485                    endpoint.full_offset = entry.range.start;
486                    endpoint.bias = self.start_bias;
487                    let start = O::from_anchor(&endpoint, &content);
488                    endpoint.full_offset = entry.range.end;
489                    endpoint.bias = self.end_bias;
490                    let end = O::from_anchor(&endpoint, &content);
491                    Some((ix, start..end, &entry.value))
492                } else {
493                    None
494                }
495            })
496    }
497}
498
499impl<T: Clone> sum_tree::Item for AnchorRangeMultimapEntry<T> {
500    type Summary = AnchorRangeMultimapSummary;
501
502    fn summary(&self) -> Self::Summary {
503        AnchorRangeMultimapSummary {
504            start: self.range.start,
505            end: self.range.end,
506            min_start: self.range.start,
507            max_end: self.range.end,
508            count: 1,
509        }
510    }
511}
512
513impl Default for AnchorRangeMultimapSummary {
514    fn default() -> Self {
515        Self {
516            start: FullOffset(0),
517            end: FullOffset::MAX,
518            min_start: FullOffset::MAX,
519            max_end: FullOffset(0),
520            count: 0,
521        }
522    }
523}
524
525impl sum_tree::Summary for AnchorRangeMultimapSummary {
526    type Context = ();
527
528    fn add_summary(&mut self, other: &Self, _: &Self::Context) {
529        self.min_start = self.min_start.min(other.min_start);
530        self.max_end = self.max_end.max(other.max_end);
531
532        #[cfg(debug_assertions)]
533        {
534            let start_comparison = self.start.cmp(&other.start);
535            assert!(start_comparison <= Ordering::Equal);
536            if start_comparison == Ordering::Equal {
537                assert!(self.end.cmp(&other.end) >= Ordering::Equal);
538            }
539        }
540
541        self.start = other.start;
542        self.end = other.end;
543        self.count += other.count;
544    }
545}
546
547impl Default for FullOffsetRange {
548    fn default() -> Self {
549        Self {
550            start: FullOffset(0),
551            end: FullOffset::MAX,
552        }
553    }
554}
555
556impl<'a> sum_tree::Dimension<'a, AnchorRangeMultimapSummary> for usize {
557    fn add_summary(&mut self, summary: &'a AnchorRangeMultimapSummary, _: &()) {
558        *self += summary.count;
559    }
560}
561
562impl<'a> sum_tree::Dimension<'a, AnchorRangeMultimapSummary> for FullOffsetRange {
563    fn add_summary(&mut self, summary: &'a AnchorRangeMultimapSummary, _: &()) {
564        self.start = summary.start;
565        self.end = summary.end;
566    }
567}
568
569impl<'a> sum_tree::SeekTarget<'a, AnchorRangeMultimapSummary, FullOffsetRange> for FullOffsetRange {
570    fn cmp(&self, cursor_location: &FullOffsetRange, _: &()) -> Ordering {
571        Ord::cmp(&self.start, &cursor_location.start)
572            .then_with(|| Ord::cmp(&cursor_location.end, &self.end))
573    }
574}
575
576pub trait AnchorRangeExt {
577    fn cmp<'a>(&self, b: &Range<Anchor>, buffer: impl Into<Content<'a>>) -> Result<Ordering>;
578    fn to_offset<'a>(&self, content: impl Into<Content<'a>>) -> Range<usize>;
579}
580
581impl AnchorRangeExt for Range<Anchor> {
582    fn cmp<'a>(&self, other: &Range<Anchor>, buffer: impl Into<Content<'a>>) -> Result<Ordering> {
583        let buffer = buffer.into();
584        Ok(match self.start.cmp(&other.start, &buffer)? {
585            Ordering::Equal => other.end.cmp(&self.end, buffer)?,
586            ord @ _ => ord,
587        })
588    }
589
590    fn to_offset<'a>(&self, content: impl Into<Content<'a>>) -> Range<usize> {
591        let content = content.into();
592        self.start.to_offset(&content)..self.end.to_offset(&content)
593    }
594}