aisling 0.3.17

Embeddable terminal text effects and loaders for Rust TUI applications.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150

use crate::color::Color;
use crate::frame::Cell;

#[derive(Clone, Debug)]
pub(crate) struct Glyph {
    pub(crate) index: usize,
    pub(crate) x: usize,
    pub(crate) y: usize,
    pub(crate) cell: Cell,
}

#[derive(Clone, Debug)]
pub(crate) struct TextGrid {
    pub(crate) width: usize,
    pub(crate) height: usize,
    pub(crate) glyphs: Vec<Glyph>,
}

impl TextGrid {
    pub(crate) fn parse(input: &str, tab_width: usize) -> Self {
        let input = if input.is_empty() { "No Input." } else { input };
        let tab_width = tab_width.max(1);
        let mut glyphs = Vec::new();
        let mut x = 0usize;
        let mut y = 0usize;
        let mut width = 0usize;
        let mut style = Cell::default();
        let mut chars = input.chars().peekable();

        while let Some(ch) = chars.next() {
            if ch == '\x1b' && chars.peek() == Some(&'[') {
                chars.next();
                let mut seq = String::new();
                for next in chars.by_ref() {
                    let end = next.is_ascii_alphabetic();
                    seq.push(next);
                    if end {
                        break;
                    }
                }
                if seq.ends_with('m') {
                    apply_sgr(&seq[..seq.len().saturating_sub(1)], &mut style);
                }
                continue;
            }

            match ch {
                '\n' => {
                    width = width.max(x);
                    x = 0;
                    y += 1;
                }
                '\r' => x = 0,
                '\t' => {
                    let spaces = tab_width - (x % tab_width);
                    for _ in 0..spaces {
                        push_glyph(&mut glyphs, &style, ' ', x, y);
                        x += 1;
                    }
                }
                _ => {
                    push_glyph(&mut glyphs, &style, ch, x, y);
                    x += 1;
                }
            }
        }
        width = width.max(x).max(1);
        let height = (y + 1).max(1);
        Self {
            width,
            height,
            glyphs,
        }
    }
}

fn push_glyph(glyphs: &mut Vec<Glyph>, style: &Cell, ch: char, x: usize, y: usize) {
    let mut cell = style.clone();
    cell.ch = ch;
    glyphs.push(Glyph {
        index: glyphs.len(),
        x,
        y,
        cell,
    });
}

fn apply_sgr(params: &str, style: &mut Cell) {
    let values: Vec<u16> = if params.trim().is_empty() {
        vec![0]
    } else {
        params
            .split(';')
            .filter_map(|part| part.parse::<u16>().ok())
            .collect()
    };
    let mut i = 0;
    while i < values.len() {
        match values[i] {
            0 => *style = Cell::default(),
            1 => style.bold = true,
            2 => style.dim = true,
            3 => style.italic = true,
            4 => style.underline = true,
            22 => {
                style.bold = false;
                style.dim = false;
            }
            23 => style.italic = false,
            24 => style.underline = false,
            30..=37 => style.colors.fg = Some(basic_color(values[i] as u8 - 30, false)),
            40..=47 => style.colors.bg = Some(basic_color(values[i] as u8 - 40, false)),
            90..=97 => style.colors.fg = Some(basic_color(values[i] as u8 - 90, true)),
            100..=107 => style.colors.bg = Some(basic_color(values[i] as u8 - 100, true)),
            38 | 48 => {
                let is_fg = values[i] == 38;
                if values.get(i + 1) == Some(&2) && i + 4 < values.len() {
                    let color = Color::rgb(
                        values[i + 2] as u8,
                        values[i + 3] as u8,
                        values[i + 4] as u8,
                    );
                    if is_fg {
                        style.colors.fg = Some(color)
                    } else {
                        style.colors.bg = Some(color)
                    }
                    i += 4;
                } else if values.get(i + 1) == Some(&5) && i + 2 < values.len() {
                    let color = Color::from_xterm(values[i + 2] as u8);
                    if is_fg {
                        style.colors.fg = Some(color)
                    } else {
                        style.colors.bg = Some(color)
                    }
                    i += 2;
                }
            }
            39 => style.colors.fg = None,
            49 => style.colors.bg = None,
            _ => {}
        }
        i += 1;
    }
}

fn basic_color(index: u8, bright: bool) -> Color {
    let code = if bright { index + 8 } else { index };
    Color::from_xterm(code)
}