#!/usr/bin/env python3
"""Minimal Minecraft RCON client (stdlib only).

Usage: python3 rcon.py <host> <port> <password> <command> [command ...]
Exit non-zero if the server reports a failure.
"""
import socket
import struct
import sys


class Rcon:
    def __init__(self, host: str, port: int, password: str, timeout: float = 10.0):
        self.host, self.port, self.password = host, port, password
        self.timeout = timeout
        self._id = 0

    def _send(self, sock: socket.socket, ptype: int, body: str) -> int:
        self._id += 1
        rid = self._id
        payload = struct.pack("<ii", rid, ptype) + body.encode("utf-8") + b"\x00\x00"
        sock.sendall(struct.pack("<i", len(payload)) + payload)
        return rid

    def _recv(self, sock: socket.socket):
        raw = b""
        while len(raw) < 4:
            chunk = sock.recv(4 - len(raw))
            if not chunk:
                raise ConnectionError("RCON connection closed")
            raw += chunk
        (length,) = struct.unpack("<i", raw)
        body = b""
        while len(body) < length:
            chunk = sock.recv(length - len(body))
            if not chunk:
                raise ConnectionError("RCON connection closed")
            body += chunk
        rid, ptype = struct.unpack("<ii", body[:8])
        return rid, ptype, body[8:-2].decode("utf-8", "replace")

    def command(self, cmd: str) -> str:
        with socket.create_connection((self.host, self.port), timeout=self.timeout) as sock:
            sock.settimeout(self.timeout)
            rid = self._send(sock, 3, self.password)
            rid2, _, _ = self._recv(sock)
            if rid2 == -1:
                raise PermissionError("RCON auth failed")
            self._send(sock, 2, cmd)
            _, _, text = self._recv(sock)
            return text


def main(argv):
    if len(argv) < 5:
        print(__doc__)
        return 2
    host, port, password = argv[1], int(argv[2]), argv[3]
    rc = 0
    for cmd in argv[4:]:
        try:
            out = Rcon(host, port, password).command(cmd)
        except Exception as exc:  # noqa: BLE001 - CLI surface
            print(f"! {cmd}: {exc}", file=sys.stderr)
            rc = 1
            continue
        if out.strip():
            print(out.strip())
        lowered = out.lower()
        if "unknown" in lowered or "failed" in lowered or "error" in lowered:
            rc = 1
    return rc


if __name__ == "__main__":
    raise SystemExit(main(sys.argv))