# -*- coding: utf-8 -*-
"""随身 WiFi（Debian）远程执行小工具。

用法：
    python _build/devssh.py "命令"            # 跑一条命令
    python _build/devssh.py --script 文件     # 跑一段脚本
"""
from __future__ import annotations

import sys
import time
from pathlib import Path

import paramiko

# 随身 WiFi（Debian）的地址。
#
# 这台设备跟着教室网络走，地址会变：
#   192.168.2.156  ->  192.168.10.105（换网络了）
# 所以优先读环境变量 YKXMZ_DEV_HOST，没有才用下面的默认值。
# 换网络时不用改代码：
#     $env:YKXMZ_DEV_HOST = "192.168.10.105"
import os

HOST = os.environ.get("YKXMZ_DEV_HOST", "192.168.10.105")
USER = "root"
PASSWORD = os.environ.get("YKXMZ_DEV_PASS", "1313144")

# 旧地址留一份，方便回退或同时探测
HOST_FALLBACKS = ("192.168.10.105", "192.168.2.156")


def run(command: str, timeout: int = 600, quiet: bool = False) -> tuple:
    client = paramiko.SSHClient()
    client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
    client.connect(HOST, username=USER, password=PASSWORD, timeout=15,
                   banner_timeout=20, auth_timeout=20,
                   look_for_keys=False, allow_agent=False)
    try:
        _stdin, stdout, stderr = client.exec_command(command, timeout=timeout)
        out = stdout.read().decode("utf-8", "replace")
        err = stderr.read().decode("utf-8", "replace")
        code = stdout.channel.recv_exit_status()
        if not quiet:
            if out.strip():
                print(out.rstrip())
            if err.strip():
                print("[stderr] " + err.rstrip())
        return code, out, err
    finally:
        client.close()


def upload(local: str, remote: str, mode: int = 0o644) -> None:
    client = paramiko.SSHClient()
    client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
    client.connect(HOST, username=USER, password=PASSWORD, timeout=15,
                   look_for_keys=False, allow_agent=False)
    try:
        sftp = client.open_sftp()
        sftp.put(local, remote)
        sftp.chmod(remote, mode)
        sftp.close()
        print(f"  已上传 {Path(local).name} -> {remote}")
    finally:
        client.close()


def download(remote: str, local: str) -> None:
    client = paramiko.SSHClient()
    client.set_missing_host_key_policy(paramiko.AutoAddPolicy())
    client.connect(HOST, username=USER, password=PASSWORD, timeout=15,
                   look_for_keys=False, allow_agent=False)
    try:
        sftp = client.open_sftp()
        sftp.get(remote, local)
        sftp.close()
        print(f"  已下载 {remote} -> {local}")
    finally:
        client.close()


if __name__ == "__main__":
    if len(sys.argv) < 2:
        print(__doc__)
        sys.exit(1)
    if sys.argv[1] == "--script":
        run(Path(sys.argv[2]).read_text(encoding="utf-8"), timeout=600)
    else:
        args = sys.argv[1:]
        timeout = 600
        if args and args[0] == '--timeout':
            timeout = int(args[1])
            args = args[2:]
        run(" ".join(args), timeout=timeout)