1use std::ops::Range;
 2
 3use gpui::{HighlightStyle, StyledText};
 4
 5use crate::{prelude::*, LabelCommon, LabelLike, LabelSize, LineHeightStyle};
 6
 7#[derive(IntoElement)]
 8pub struct HighlightedLabel {
 9    base: LabelLike,
10    label: SharedString,
11    highlight_indices: Vec<usize>,
12}
13
14impl HighlightedLabel {
15    /// Constructs a label with the given characters highlighted.
16    /// Characters are identified by UTF-8 byte position.
17    pub fn new(label: impl Into<SharedString>, highlight_indices: Vec<usize>) -> Self {
18        Self {
19            base: LabelLike::new(),
20            label: label.into(),
21            highlight_indices,
22        }
23    }
24}
25
26impl LabelCommon for HighlightedLabel {
27    fn size(mut self, size: LabelSize) -> Self {
28        self.base = self.base.size(size);
29        self
30    }
31
32    fn line_height_style(mut self, line_height_style: LineHeightStyle) -> Self {
33        self.base = self.base.line_height_style(line_height_style);
34        self
35    }
36
37    fn color(mut self, color: Color) -> Self {
38        self.base = self.base.color(color);
39        self
40    }
41
42    fn strikethrough(mut self, strikethrough: bool) -> Self {
43        self.base = self.base.strikethrough(strikethrough);
44        self
45    }
46}
47
48impl RenderOnce for HighlightedLabel {
49    fn render(self, cx: &mut WindowContext) -> impl IntoElement {
50        let highlight_color = cx.theme().colors().text_accent;
51
52        let mut highlight_indices = self.highlight_indices.iter().copied().peekable();
53        let mut highlights: Vec<(Range<usize>, HighlightStyle)> = Vec::new();
54
55        while let Some(start_ix) = highlight_indices.next() {
56            let mut end_ix = start_ix;
57
58            loop {
59                end_ix = end_ix + self.label[end_ix..].chars().next().unwrap().len_utf8();
60                if let Some(&next_ix) = highlight_indices.peek() {
61                    if next_ix == end_ix {
62                        end_ix = next_ix;
63                        highlight_indices.next();
64                        continue;
65                    }
66                }
67                break;
68            }
69
70            highlights.push((
71                start_ix..end_ix,
72                HighlightStyle {
73                    color: Some(highlight_color),
74                    ..Default::default()
75                },
76            ));
77        }
78
79        let mut text_style = cx.text_style().clone();
80        text_style.color = self.base.color.color(cx);
81
82        self.base
83            .child(StyledText::new(self.label).with_highlights(&text_style, highlights))
84    }
85}