#!/usr/bin/env python3

import argparse
import json
from pathlib import Path


def main():
    parser = argparse.ArgumentParser(
        description="Convert a passwd/group/shadow file to a directory of systemd JSON user records.",
    )
    parser.add_argument(
        "passwd_file",
        type=Path,
        help="Path to the passwd file.",
    )
    parser.add_argument(
        "group_file",
        type=Path,
        help="Path to the group file.",
    )
    parser.add_argument(
        "shadow_file",
        type=Path,
        help="Path to the shadow file.",
    )
    parser.add_argument(
        "output_dir",
        type=Path,
        help="Path to a directory to store json user records.",
    )
    args = parser.parse_args()

    parsed_users = parse_passwd_file(args.passwd_file)
    parsed_groups = parse_group_file(args.group_file)
    parsed_shadow = parse_shadow_file(args.shadow_file)

    for user in parsed_users:
        print(json.dumps(user, indent=2))

    for group in parsed_groups:
        print(json.dumps(group, indent=2))

    for shadow_entry in parsed_shadow:
        print(json.dumps(shadow_entry, indent=2))


def parse_passwd_file(passwd_file: Path) -> list[dict]:
    users = []
    with passwd_file.open("r") as f:
        for line in f:
            if line.startswith("#") or not line.strip():
                continue
            parts = line.strip().split(":")
            if len(parts) < 7:
                print(f"Warning: Skipping malformed line: {line.strip()}")
                continue
            user = {
                "name": parts[0],
                "uid": int(parts[2]),
                "gid": int(parts[3]),
                "gecos": parse_passwd_gecos(parts[4]),
                "home": parts[5],
                "shell": parts[6],
            }
            users.append(user)
    return users


def parse_passwd_gecos(gecos: str) -> dict:
    parts = gecos.split(",")
    return {
        "full_name": parts[0] if len(parts) > 0 else "",
        "room_number": parts[1] if len(parts) > 1 else "",
        "work_phone": parts[2] if len(parts) > 2 else "",
        "home_phone": parts[3] if len(parts) > 3 else "",
        "other": parts[4] if len(parts) > 4 else "",
    }


def parse_group_file(group_file: Path) -> list[dict]:
    groups = []
    with group_file.open("r") as f:
        for line in f:
            if line.startswith("#") or not line.strip():
                continue
            parts = line.strip().split(":")
            if len(parts) < 4:
                print(f"Warning: Skipping malformed line: {line.strip()}")
                continue
            group = {
                "name": parts[0],
                "gid": int(parts[2]),
                "members": parts[3].split(",") if parts[3] else [],
            }
            groups.append(group)
    return groups


def parse_shadow_file(shadow_file: Path) -> list[dict]:
    shadow_entries = []
    with shadow_file.open("r") as f:
        for line in f:
            if line.startswith("#") or not line.strip():
                continue
            parts = line.strip().split(":")
            if len(parts) < 9:
                print(f"Warning: Skipping malformed line: {line.strip()}")
                continue
            shadow_entry = {
                "name": parts[0],
                "password": parts[1],
                "last_change": int(parts[2]) if parts[2].isdigit() else None,
                "min_days": int(parts[3]) if parts[3].isdigit() else None,
                "max_days": int(parts[4]) if parts[4].isdigit() else None,
                "warn_days": int(parts[5]) if parts[5].isdigit() else None,
                "inactive_days": int(parts[6]) if parts[6].isdigit() else None,
                "expire_date": int(parts[7]) if parts[7].isdigit() else None,
                "reserved": parts[8],
            }
            shadow_entries.append(shadow_entry)
    return shadow_entries


if __name__ == "__main__":
    main()