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//! Write ANSI escape code colored text
use std::io::Write;
fn main() -> Result<(), lexopt::Error> {
let args = Args::parse()?;
let stdout = std::io::stdout();
let mut stdout = stdout.lock();
for fixed in 0..16 {
let color = anstyle::Ansi256Color(fixed)
.into_ansi()
.expect("4-bit range used");
let style = style(color, args.layer, args.effects);
let _ = print_number(&mut stdout, fixed, style);
if fixed == 7 || fixed == 15 {
let _ = writeln!(&mut stdout);
}
}
for fixed in 16..232 {
let col = (fixed - 16) % 36;
if col == 0 {
let _ = writeln!(stdout);
}
let color = anstyle::Ansi256Color(fixed);
let style = style(color, args.layer, args.effects);
let _ = print_number(&mut stdout, fixed, style);
}
let _ = writeln!(stdout);
let _ = writeln!(stdout);
for fixed in 232..=255 {
let color = anstyle::Ansi256Color(fixed);
let style = style(color, args.layer, args.effects);
let _ = print_number(&mut stdout, fixed, style);
}
let _ = writeln!(stdout);
Ok(())
}
fn style(
color: impl Into<anstyle::Color>,
layer: Layer,
effects: anstyle::Effects,
) -> anstyle::Style {
let color = color.into();
(match layer {
Layer::Fg => anstyle::Style::new().fg_color(Some(color)),
Layer::Bg => anstyle::Style::new().bg_color(Some(color)),
Layer::Underline => anstyle::Style::new().underline_color(Some(color)),
}) | effects
}
fn print_number(
stdout: &mut std::io::StdoutLock<'_>,
fixed: u8,
style: anstyle::Style,
) -> std::io::Result<()> {
write!(stdout, "{style}{fixed:>3X}{style:#}",)
}
#[derive(Default)]
struct Args {
effects: anstyle::Effects,
layer: Layer,
}
#[derive(Copy, Clone, Default)]
enum Layer {
#[default]
Fg,
Bg,
Underline,
}
impl Args {
fn parse() -> Result<Self, lexopt::Error> {
use lexopt::prelude::*;
let mut res = Args::default();
let mut args = lexopt::Parser::from_env();
while let Some(arg) = args.next()? {
match arg {
Long("layer") => {
res.layer = args.value()?.parse_with(|s| match s {
"fg" => Ok(Layer::Fg),
"bg" => Ok(Layer::Bg),
"underline" => Ok(Layer::Underline),
_ => Err("expected values fg, bg, underline"),
})?;
}
Long("effect") => {
const EFFECTS: [(&str, anstyle::Effects); 12] = [
("bold", anstyle::Effects::BOLD),
("dimmed", anstyle::Effects::DIMMED),
("italic", anstyle::Effects::ITALIC),
("underline", anstyle::Effects::UNDERLINE),
("double_underline", anstyle::Effects::DOUBLE_UNDERLINE),
("curly_underline", anstyle::Effects::CURLY_UNDERLINE),
("dotted_underline", anstyle::Effects::DOTTED_UNDERLINE),
("dashed_underline", anstyle::Effects::DASHED_UNDERLINE),
("blink", anstyle::Effects::BLINK),
("invert", anstyle::Effects::INVERT),
("hidden", anstyle::Effects::HIDDEN),
("strikethrough", anstyle::Effects::STRIKETHROUGH),
];
let effect = args.value()?.parse_with(|s| {
EFFECTS
.into_iter()
.find(|(name, _)| *name == s)
.map(|(_, effect)| effect)
.ok_or_else(|| {
format!(
"expected one of {}",
EFFECTS
.into_iter()
.map(|(n, _)| n)
.collect::<Vec<_>>()
.join(", ")
)
})
})?;
res.effects = res.effects.insert(effect);
}
_ => return Err(arg.unexpected()),
}
}
Ok(res)
}
}