"""
Convert P7B (PKCS#7) certificate to PEM format for use with the server
Use this if you have a P7B file and need to extract PEM certificates
"""

import subprocess
import sys
import os


def convert_p7b_to_pem(p7b_file, cert_output="cert.pem", extract_key=False):
    """
    Convert P7B certificate to PEM format

    Args:
        p7b_file: Input P7B (PKCS#7) file
        cert_output: Output PEM certificate file
        extract_key: If True, try to extract private key (rarely works with P7B)
    """

    # Check if OpenSSL is available
    try:
        subprocess.run(["openssl", "version"], capture_output=True, check=True)
    except (subprocess.CalledProcessError, FileNotFoundError):
        print("ERROR: OpenSSL not found!")
        print("\nFor Windows, you can:")
        print(
            "1. Install OpenSSL from: https://slproweb.com/products/Win32OpenSSL.html"
        )
        print("2. Or use Git Bash which includes OpenSSL")
        print("3. Or use WSL (Windows Subsystem for Linux)")
        return False

    # Check if input file exists
    if not os.path.exists(p7b_file):
        print(f"ERROR: P7B file not found: {p7b_file}")
        print(f"Current directory: {os.getcwd()}")
        return False

    print(f"Converting {p7b_file} to PEM format...")

    # Convert P7B to PEM
    cmd = ["openssl", "pkcs7", "-print_certs", "-in", p7b_file, "-out", cert_output]

    try:
        result = subprocess.run(cmd, check=True, capture_output=True, text=True)

        if os.path.exists(cert_output):
            print(f"\n✓ PEM certificate created: {os.path.abspath(cert_output)}")
            print(f"  File size: {os.path.getsize(cert_output)} bytes")

            # Check what was extracted
            with open(cert_output, "r") as f:
                content = f.read()
                cert_count = content.count("BEGIN CERTIFICATE")
                print(f"  Certificates found: {cert_count}")

            print("\n" + "=" * 60)
            print("IMPORTANT:")
            print("=" * 60)
            print("⚠️  P7B files usually contain ONLY certificates, not private keys!")
            print("\nTo run an HTTPS server, you need:")
            print("1. Certificate (cert.pem) - ✓ Extracted")
            print("2. Private Key (key.pem) - ✗ NOT in P7B file")
            print("\nIf you don't have the private key:")
            print("- Generate a new certificate pair: python generate_cert.py")
            print("- Or obtain the private key from your certificate provider")
            print("=" * 60)

            return True
        else:
            print("ERROR: Output file was not created")
            return False

    except subprocess.CalledProcessError as e:
        print(f"ERROR: Conversion failed: {e}")
        if e.stderr:
            print(f"OpenSSL error: {e.stderr}")
        return False


if __name__ == "__main__":
    import argparse

    parser = argparse.ArgumentParser(
        description="Convert P7B (PKCS#7) certificate to PEM format"
    )
    parser.add_argument("p7b_file", help="Input P7B certificate file")
    parser.add_argument(
        "--output",
        default="cert.pem",
        help="Output PEM certificate file (default: cert.pem)",
    )

    args = parser.parse_args()

    print("=" * 60)
    print("P7B to PEM Certificate Converter")
    print("=" * 60)
    print()

    success = convert_p7b_to_pem(args.p7b_file, args.output)

    if success:
        print("\n✓ Conversion complete!")
        print("\nNext steps:")
        print("1. If you have the private key separately, use it with --ssl-key")
        print("2. If not, generate a new certificate: python generate_cert.py")
    else:
        sys.exit(1)