Pc!

#!/usr/bin/env python3
"""Run a PROTEL source file invoked via shebang (Introductory Manual §7.0.5).

Pc! — pronounced "P c Bang" — is the shebang helper and command-line shortcut
for running .P programs. The kernel executes: Pc! /path/to/script.P [args]
"""

from __future__ import annotations

import os
import sys
from pathlib import Path

_ROOT = Path(__file__).resolve().parent
_PC = _ROOT / "Pc"


def main() -> int:
    if len(sys.argv) < 2:
        print(
            "Pc!: missing PROTEL source path "
            "(use #!/usr/bin/env Pc! in a .P file)",
            file=sys.stderr,
        )
        return 2

    source = Path(sys.argv[1]).resolve()
    program_args = sys.argv[2:]

    if not _PC.is_file():
        print(f"Pc!: cannot find Pc driver at '{_PC}'", file=sys.stderr)
        return 1

    argv = [str(_PC), str(source), "--run", "--", *program_args]
    os.execv(str(_PC), argv)
    return 1


if __name__ == "__main__":
    raise SystemExit(main())