dynix/src/color.rs

use std::{
    env,
    sync::{LazyLock, OnceLock},
};

#[allow(unused_imports)]
use crate::prelude::*;

pub static CLI_ENABLE_COLOR: OnceLock<bool> = OnceLock::new();

fn is_color_reqd() -> bool {
    CLI_ENABLE_COLOR.get().copied().unwrap_or(false)
}

fn is_clicolor_forced() -> bool {
    env::var("CLICOLOR_FORCE")
        .map(|value| {
            if value.is_empty() || value == "0" {
                false
            } else {
                true
            }
        })
        .unwrap_or(false)
}

pub static SHOULD_COLOR: LazyLock<bool> = LazyLock::new(|| is_clicolor_forced() || is_color_reqd());

/// Silly wrapper around LazyLock<&'static str> to impl Display.
pub(crate) struct _LazyLockDisplay(LazyLock<&'static str>);
impl Display for _LazyLockDisplay {
    fn fmt(&self, f: &mut Formatter) -> FmtResult {
        Display::fmt(&*self.0, f)
    }
}

pub(crate) const ANSI_GREEN: _LazyLockDisplay = _LazyLockDisplay(LazyLock::new(|| {
    SHOULD_COLOR.then_some("\x1b[32m").unwrap_or_default()
}));

pub(crate) const ANSI_MAGENTA: _LazyLockDisplay = _LazyLockDisplay(LazyLock::new(|| {
    SHOULD_COLOR.then_some("\x1b[35m").unwrap_or_default()
}));

pub(crate) const ANSI_CYAN: _LazyLockDisplay = _LazyLockDisplay(LazyLock::new(|| {
    SHOULD_COLOR.then_some("\x1b[36m").unwrap_or_default()
}));

pub(crate) const ANSI_RESET: _LazyLockDisplay = _LazyLockDisplay(LazyLock::new(|| {
    SHOULD_COLOR
        // C'mon rustfmt, just format it to match ^.
        .then_some("\x1b[0m")
        .unwrap_or_default()
}));