//! The `h5rs` binary. A panic anywhere is a bug: it is caught, reported as
//! an internal error and turned into exit status 3, never a crash.

use std::io::Write;
use std::panic::{self, AssertUnwindSafe};

use clawhdf5_tools::cli::Out;

/// Exit status for an internal error (a caught panic).
const INTERNAL_ERROR: i32 = 3;

fn main() {
    panic::set_hook(Box::new(|info| {
        let msg = if let Some(s) = info.payload().downcast_ref::<&str>() {
            (*s).to_string()
        } else if let Some(s) = info.payload().downcast_ref::<String>() {
            s.clone()
        } else {
            "unknown panic".into()
        };
        let at = info
            .location()
            .map(|l| format!(" at {}:{}", l.file(), l.line()))
            .unwrap_or_default();
        eprintln!("h5rs: internal error (this is a bug; please report it): {msg}{at}");
    }));
    let argv: Vec<String> = std::env::args().skip(1).collect();
    let stdout = std::io::stdout();
    let mut o = std::io::BufWriter::new(stdout.lock());
    let mut e = std::io::stderr();
    let result = panic::catch_unwind(AssertUnwindSafe(|| {
        let mut out = Out {
            o: &mut o,
            e: &mut e,
        };
        clawhdf5_tools::run(argv, &mut out)
    }));
    let code = match result {
        Ok(Ok(code)) => match o.flush() {
            Ok(()) => code,
            Err(err) if err.kind() == std::io::ErrorKind::BrokenPipe => code,
            Err(err) => {
                eprintln!("h5rs: {err}");
                2
            }
        },
        Ok(Err(err)) if err.kind() == std::io::ErrorKind::BrokenPipe => 0,
        Ok(Err(err)) => {
            eprintln!("h5rs: {err}");
            2
        }
        Err(_) => {
            let _ = o.flush();
            INTERNAL_ERROR
        }
    };
    std::process::exit(code);
}