anyways/
align.rs

1//! Padding utilities
2
3use crate::formatter::get_length;
4use std::fmt;
5use std::fmt::Write;
6
7pub struct PaddingEntry {
8    pub text: String,
9    pub width: usize,
10    pub alignment: Alignment,
11}
12
13pub enum Alignment {
14    Left,
15    Center,
16    Right,
17}
18
19pub fn align(
20    entries: &Vec<PaddingEntry>,
21    max_width: usize,
22    pad_char: char,
23    mut func: impl FnMut(String) -> fmt::Result,
24) -> fmt::Result {
25    let mut offset = 0;
26    let mut line = String::new();
27    for entry in entries {
28        let text = &entry.text;
29        let length = get_length(text);
30        if length > entry.width {
31            offset += length - entry.width;
32            line.push_str(text);
33        } else {
34            let mut padding_size = entry.width - length;
35
36            // try to correct the offset
37            let offset_amount = offset.clamp(0, padding_size);
38            offset -= offset_amount;
39            padding_size -= offset_amount;
40
41            let padding = pad_char.to_string().repeat(padding_size);
42            match entry.alignment {
43                Alignment::Left => {
44                    write!(&mut line, "{text}{padding}")?;
45                }
46                Alignment::Center => {
47                    let (left_padding, right_padding) = padding.split_at(padding.len() / 2);
48                    write!(&mut line, "{left_padding}{text}{right_padding}")?;
49                }
50                Alignment::Right => {
51                    write!(&mut line, "{padding}{text}")?;
52                }
53            }
54        }
55    }
56
57    if get_length(&line) > max_width {
58        let mut line_builder = String::new();
59        for ch in line.chars() {
60            line_builder.push(ch);
61            if get_length(&line_builder) >= max_width {
62                func(line_builder)?;
63                line_builder = String::new();
64            }
65        }
66
67        if !line_builder.is_empty() {
68            func(line_builder)?;
69        }
70    } else {
71        func(line)?;
72    }
73
74    Ok(())
75}