use clap::{Arg, ArgAction, Command};
use std::{io, ffi::CString, process};
use super::Cmd;

#[derive(Debug, Default)]
pub struct Unlink;

impl Cmd for Unlink {
    fn cli(&self) -> clap::Command {
        Command::new("unlink")
            .about("call the unlink function to remove the specified file")
            .author("Nathan Fisher")
            .version(env!("CARGO_PKG_VERSION"))
            .args([
                Arg::new("verbose")
                    .help("display user feedback upon success")
                    .short('v')
                    .long("verbose")
                    .action(ArgAction::SetTrue),
                Arg::new("file")
                    .value_name("FILE")
                    .required(true)
                    .num_args(1..),
            ])
    }

    fn run(&self, matches: Option<&clap::ArgMatches>) -> Result<(), Box<dyn std::error::Error>> {
        let Some(matches) = matches else {
            return Err(Box::new(io::Error::new(io::ErrorKind::Other, "no input")));
        };
        if let Some(files) = matches.get_many::<String>("file") {
            for f in files {
                let fname = CString::new(f.as_str())?;
                let ret = unsafe { libc::unlink(fname.as_ptr()) };
                if matches.get_flag("verbose") && ret == 0 {
                    println!("unlink: {f}");
                } else if ret != 0 {
                    let err = io::Error::last_os_error();
                    eprintln!("unlink: cannot unlink {f}: {err}");
                    process::exit(ret);
                }
            }
        }
        Ok(())
    }

    fn path(&self) -> Option<crate::Path> {
        Some(crate::Path::UsrBin)
    }
}