#!python3
# dlitz 2025

from contextlib import ExitStack, contextmanager
import multiprocessing
import subprocess
import os
import re

class PKCS12Exporter:

    openssl_prog = "openssl"

    def export_pkcs12(self, privkey_data, cert_data, chain_data, passphrase):
        assert re.search(r"^-----BEGIN (.*) PRIVATE KEY-----\n", privkey_data, re.M)
        assert re.search(r"^-----BEGIN CERTIFICATE-----\n", cert_data, re.M)
        assert "PRIVATE KEY" not in cert_data
        assert chain_data is None or "PRIVATE KEY" not in chain_data

        fullchain_data = cert_data + "\n" + (chain_data or "") + "\n"

        all_data = privkey_data + "\n" + fullchain_data

        with ExitStack() as stack:
            passphrase_r, passphrase_w = stack.enter_context(self.open_pipes(text=True))

            cmd = [
                self.openssl_prog,
                "pkcs12",
                "-export",
                "-passout", f"fd:{passphrase_r.fileno():d}",
                "-macalg", "SHA256",
                "-keypbe", "AES-256-CBC",
                "-certpbe", "NONE",
            ]

            passphrase_proc = multiprocessing.Process(target=self.data_writer, args=(passphrase_w, passphrase))
            passphrase_proc.start()
            passphrase_w.close()

            print(cmd)
            #subprocess.run(["bash", "-x", "-c", "ls -l /dev/fd/; cat /dev/fd/5; cat /dev/fd/3"], pass_fds=(passphrase_r.fileno(), privkey_r.fileno()))
            #subprocess.run(cmd, pass_fds=(passphrase_r.fileno(), privkey_r.fileno()), input=fullchain_data.encode())
            subprocess.run(cmd, pass_fds=(passphrase_r.fileno(), privkey_r.fileno()), input=all_data.encode())

            passphrase_proc.terminate()
            passphrase_proc.

    @contextmanager
    def open_pipes(self, *, text=False):
        rfd, wfd = os.pipe()
        rfile = wfile = None
        try:
            rfile = open(rfd, "r" if text else "rb")
            wfile = open(wfd, "w" if text else "wb")
        except:
            if rfile is not None:
                rfile.close()
            else:
                os.close(rfd)
            if wfile is not None:
                wfile.close()
            else:
                os.close(wfd)
        with rfile as r, wfile as w:
            yield r, w

    @classmethod
    def data_writer(cls, file, data):
        file.write(data)
        file.close()