#!/usr/bin/env python3
"""V1 工厂 TCP 命令客户端；发送任何命令都必须显式使用 --execute。"""

from __future__ import annotations

import argparse
import json
import socket
import struct
import sys

MAX_DATA = 16 * 1024 * 1024


def receive_exact(sock: socket.socket, length: int) -> bytes:
    chunks = bytearray()
    while len(chunks) < length:
        part = sock.recv(length - len(chunks))
        if not part:
            raise ConnectionError("peer closed before complete V1 frame arrived")
        chunks.extend(part)
    return bytes(chunks)


def main() -> int:
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument("host", help="device IP selected from discovery results")
    parser.add_argument("command", help="V1 CMD, decimal or 0x-prefixed")
    parser.add_argument("--data", default="", help="UTF-8 JSON/text payload (omit for empty Data)")
    parser.add_argument("--timeout", type=float, default=8.0)
    parser.add_argument("--execute", action="store_true", help="actually send the command")
    args = parser.parse_args()
    try:
        command = int(args.command, 0)
        payload = args.data.encode("utf-8")
        if not 0 <= command <= 0xFFFFFFFF:
            raise ValueError("CMD must fit uint32")
        if len(payload) > MAX_DATA:
            raise ValueError("request Data exceeds 16 MiB limit")
        if args.data:
            json.loads(args.data)  # V1 factory command payloads are documented JSON.
        if not args.execute:
            print(json.dumps({"preflight_only": True, "host": args.host, "port": 4941,
                              "command": "0x%08X" % command, "data_bytes": len(payload),
                              "message": "No network connection opened; add --execute to send."}, ensure_ascii=False))
            return 0
        request = struct.pack("!II", command, len(payload)) + payload
        with socket.create_connection((args.host, 4941), timeout=args.timeout) as sock:
            sock.settimeout(args.timeout)
            sock.sendall(request)
            header = receive_exact(sock, 8)
            response_command, response_length = struct.unpack("!II", header)
            if response_length > MAX_DATA:
                raise ValueError("response Data exceeds 16 MiB limit")
            response = receive_exact(sock, response_length)
        result = {"request_command": "0x%08X" % command,
                  "response_command": "0x%08X" % response_command,
                  "response_length": response_length,
                  "response_data": response.decode("utf-8", errors="replace")}
        print(json.dumps(result, ensure_ascii=False))
        if response_command != command:
            return 2
        return 0
    except (OSError, ValueError, ConnectionError, json.JSONDecodeError) as exc:
        print("V1 command error: %s" % exc, file=sys.stderr)
        return 1


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