lean-ctx 3.4.5

pub(crate) fn print_savings(original: usize, sent: usize) {
    let saved = original.saturating_sub(sent);
    if original > 0 && saved > 0 {
        let pct = (saved as f64 / original as f64 * 100.0).round() as usize;
        println!("[{saved} tok saved ({pct}%)]");
    }
}

pub fn load_shell_history_pub() -> Vec<String> {
    load_shell_history()
}

pub(crate) fn load_shell_history() -> Vec<String> {
    let shell = std::env::var("SHELL").unwrap_or_default();
    let Some(home) = dirs::home_dir() else {
        return Vec::new();
    };

    let history_file = if shell.contains("zsh") {
        home.join(".zsh_history")
    } else if shell.contains("fish") {
        home.join(".local/share/fish/fish_history")
    } else if cfg!(windows) && shell.is_empty() {
        home.join("AppData")
            .join("Roaming")
            .join("Microsoft")
            .join("Windows")
            .join("PowerShell")
            .join("PSReadLine")
            .join("ConsoleHost_history.txt")
    } else {
        home.join(".bash_history")
    };

    match std::fs::read_to_string(&history_file) {
        Ok(content) => content
            .lines()
            .filter_map(|l| {
                let trimmed = l.trim();
                if trimmed.starts_with(':') {
                    trimmed
                        .split(';')
                        .nth(1)
                        .map(std::string::ToString::to_string)
                } else {
                    Some(trimmed.to_string())
                }
            })
            .filter(|l| !l.is_empty())
            .collect(),
        Err(_) => Vec::new(),
    }
}

pub(crate) fn format_tokens_cli(tokens: u64) -> String {
    if tokens >= 1_000_000 {
        format!("{:.1}M", tokens as f64 / 1_000_000.0)
    } else if tokens >= 1_000 {
        format!("{:.1}K", tokens as f64 / 1_000.0)
    } else {
        format!("{tokens}")
    }
}