use super::Cmd;
use crate::mode::Parser;
use clap::{Arg, ArgAction, ArgMatches, Command};
use std::{error::Error, ffi::CString, io};

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

impl Cmd for MkFifo {
    fn cli(&self) -> clap::Command {
        Command::new("mkfifo")
            .about("make FIFO special files")
            .author("Nathan Fisher")
            .version(env!("CARGO_PKG_VERSION"))
            .args([
                Arg::new("mode")
                    .help(
                        "Set  the  file  permission  bits of the newly-created \
                        FIFO to the specified mode value.",
                    )
                    .long_help(
                        "Set  the  file  permission  bits of the newly-created \
                        FIFO to the specified mode value. The mode option-argument \
                        shall be the same as the mode operand defined for the \
                        chmod  utility. In the symbolic_mode strings, the op \
                        characters '+' and '-' shall be interpreted relative to \
                        an assumed initial mode of a=rw.",
                    )
                    .short('m')
                    .long("mode")
                    .value_name("MODE")
                    .num_args(1),
                Arg::new("verbose")
                    .help("print a diagnostic for every pipe created")
                    .short('v')
                    .long("verbose")
                    .action(ArgAction::SetTrue),
                Arg::new("file").num_args(1..).required(true),
            ])
    }

    fn run(&self, matches: Option<&ArgMatches>) -> Result<(), Box<dyn Error>> {
        let Some(matches) = matches else {
            return Err(io::Error::new(io::ErrorKind::Other, "no input").into());
        };
        let mode = if let Some(m) = matches.get_one::<String>("mode") {
            Parser::new(0o666).parse(m)?
        } else {
            0o666
        };
        if let Some(files) = matches.get_many::<String>("file") {
            for f in files {
                let fname = CString::new(f.as_str())?;
                let res = unsafe { libc::mkfifo(fname.as_ptr(), mode) };
                if res != 0 {
                    return Err(io::Error::last_os_error().into());
                }
                if matches.get_flag("verbose") {
                    println!(
                        "{}: created pipe '{f}' with mode {mode:o}",
                        self.cli().get_name()
                    );
                }
            }
        }
        Ok(())
    }

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