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