use crate::Path;
use clap::{Arg, Command};
use std::env;

pub const PATH: Path = Path::Bin;

#[must_use]
pub fn cli() -> Command {
    Command::new("echo")
        .about("Display a line of text")
        .long_about("Echo the STRING(s) to standard output")
        .version(env!("CARGO_PKG_VERSION"))
        .author("Nathan Fisher")
        .args([
            Arg::new("inline")
                .short('n')
                .help("Do not output a trailing newline"),
            Arg::new("STRING").num_args(1..),
        ])
}

pub fn run() {
    let args: Vec<String> = env::args().collect();
    let idx = match crate::progname() {
        Some(s) if s.as_str() == "echo" => 1,
        Some(_) => 2,
        None => unreachable!(),
    };
    let len = args.len();
    let n = len > idx && args[idx] == "-n";
    let i = if n { idx + 1 } else { idx };
    for (index, arg) in args.iter().enumerate().skip(i) {
        if index < len - 1 {
            print!("{arg} ");
        } else {
            print!("{arg}");
        }
    }
    if !n {
        println!();
    }
}