1use super::{ExcerptId, MultiBufferSnapshot, ToOffset, ToPoint};
2use anyhow::{anyhow, Result};
3use std::{
4 cmp::Ordering,
5 ops::{Range, Sub},
6};
7use sum_tree::Bias;
8use text::{rope::TextDimension, Point};
9
10#[derive(Clone, Eq, PartialEq, Debug, Hash)]
11pub struct Anchor {
12 pub(crate) excerpt_id: ExcerptId,
13 pub(crate) text_anchor: text::Anchor,
14}
15
16impl Anchor {
17 pub fn min() -> Self {
18 Self {
19 excerpt_id: ExcerptId::min(),
20 text_anchor: text::Anchor::min(),
21 }
22 }
23
24 pub fn max() -> Self {
25 Self {
26 excerpt_id: ExcerptId::max(),
27 text_anchor: text::Anchor::max(),
28 }
29 }
30
31 pub fn cmp<'a>(&self, other: &Anchor, snapshot: &MultiBufferSnapshot) -> Result<Ordering> {
32 let excerpt_id_cmp = self.excerpt_id.cmp(&other.excerpt_id);
33 if excerpt_id_cmp.is_eq() {
34 if self.excerpt_id == ExcerptId::max() {
35 return Ok(Ordering::Equal);
36 }
37 self.text_anchor.cmp(
38 &other.text_anchor,
39 snapshot
40 .buffer_snapshot_for_excerpt(&self.excerpt_id)
41 .ok_or_else(|| anyhow!("excerpt {:?} not found", self.excerpt_id))?,
42 )
43 } else {
44 return Ok(excerpt_id_cmp);
45 }
46 }
47
48 pub fn bias_left(&self, snapshot: &MultiBufferSnapshot) -> Anchor {
49 if self.text_anchor.bias != Bias::Left {
50 if let Some(buffer_snapshot) = snapshot.buffer_snapshot_for_excerpt(&self.excerpt_id) {
51 return Self {
52 excerpt_id: self.excerpt_id.clone(),
53 text_anchor: self.text_anchor.bias_left(buffer_snapshot),
54 };
55 }
56 }
57 self.clone()
58 }
59
60 pub fn bias_right(&self, snapshot: &MultiBufferSnapshot) -> Anchor {
61 if self.text_anchor.bias != Bias::Right {
62 if let Some(buffer_snapshot) = snapshot.buffer_snapshot_for_excerpt(&self.excerpt_id) {
63 return Self {
64 excerpt_id: self.excerpt_id.clone(),
65 text_anchor: self.text_anchor.bias_right(buffer_snapshot),
66 };
67 }
68 }
69 self.clone()
70 }
71
72 pub fn summary<D>(&self, snapshot: &MultiBufferSnapshot) -> D
73 where
74 D: TextDimension + Ord + Sub<D, Output = D>,
75 {
76 snapshot.summary_for_anchor(self)
77 }
78}
79
80impl ToOffset for Anchor {
81 fn to_offset<'a>(&self, snapshot: &MultiBufferSnapshot) -> usize {
82 self.summary(snapshot)
83 }
84}
85
86impl ToPoint for Anchor {
87 fn to_point<'a>(&self, snapshot: &MultiBufferSnapshot) -> Point {
88 self.summary(snapshot)
89 }
90}
91
92pub trait AnchorRangeExt {
93 fn cmp(&self, b: &Range<Anchor>, buffer: &MultiBufferSnapshot) -> Result<Ordering>;
94 fn to_offset(&self, content: &MultiBufferSnapshot) -> Range<usize>;
95 fn to_point(&self, content: &MultiBufferSnapshot) -> Range<Point>;
96}
97
98impl AnchorRangeExt for Range<Anchor> {
99 fn cmp(&self, other: &Range<Anchor>, buffer: &MultiBufferSnapshot) -> Result<Ordering> {
100 Ok(match self.start.cmp(&other.start, buffer)? {
101 Ordering::Equal => other.end.cmp(&self.end, buffer)?,
102 ord @ _ => ord,
103 })
104 }
105
106 fn to_offset(&self, content: &MultiBufferSnapshot) -> Range<usize> {
107 self.start.to_offset(&content)..self.end.to_offset(&content)
108 }
109
110 fn to_point(&self, content: &MultiBufferSnapshot) -> Range<Point> {
111 self.start.to_point(&content)..self.end.to_point(&content)
112 }
113}