"""Run a command on the PVE node via the same VNC term channel the web console uses.

Usage: python3 pve_term_exec.py "<command>"
Reads ticket from /tmp/pve_t.txt (refreshed automatically if expired).
Prints the command output captured from the terminal stream.
"""
import base64
import json
import ssl
import struct
import sys
import time
import urllib.parse
import urllib.request

HOST = "https://192.168.1.51:8006"
NODE = "starhe"
CTX = ssl.create_default_context()
CTX.check_hostname = False
CTX.verify_mode = ssl.CERT_NONE


def http(path, data=None, ticket=None, csrf=None):
    body = urllib.parse.urlencode(data).encode() if data is not None else None
    req = urllib.request.Request(HOST + path, body)
    if ticket:
        req.add_header("Cookie", "PVEAuthCookie=" + ticket)
    if csrf:
        req.add_header("CSRFPreventionToken", csrf)
    with urllib.request.urlopen(req, context=CTX, timeout=30) as r:
        raw = r.read()
        return json.loads(raw)["data"] if raw else None


def login():
    d = http("/api2/json/access/ticket",
             {"username": "root@pam", "password": "yx66668888"})
    return d["ticket"], d["CSRFPreventionToken"]


def run_cmd(command, timeout=60):
    ticket, csrf = login()
    # 1. open a term proxy (VNC channel to node shell)
    r = http("/api2/json/nodes/%s/termproxy" % NODE, {}, ticket, csrf)
    port, ticket_vnc = r["port"], r["ticket"]
    user, realm_sep, _ = "root", "@", "pam"

    import socket
    sock = socket.create_connection(("192.168.1.51", port), timeout=10)
    # PVE handshake: username@realm\n ticket\n binary handshake
    sock.sendall(b"root@pam\n" + ticket_vnc.encode() + b"\n")
    gh = sock.recv(16)
    maj, mino = struct.unpack("BB", gh[0:2])
    said = sock.recv(16 * 4)
    # client sends its own handshake
    ch = struct.pack("BB", maj, mino) + b"PVEVNC Client 00" + b"\x00" * 0
    sock.sendall(ch)

    # 2. run the command in the shell by typing it and reading output
    marker = "PVEDONE%s" % int(time.time())
    payload = command + " ; echo " + marker + "\n"
    time.sleep(0.5)
    sock.sendall(payload.encode())

    buf = b""
    deadline = time.time() + timeout
    while time.time() < deadline:
        try:
            sock.settimeout(2)
            chunk = sock.recv(65536)
            if not chunk:
                break
            buf += chunk
            if marker.encode() in buf.replace(b"\x1b", b"").replace(b"[?2004l", b""):
                break
        except socket.timeout:
            if marker.encode() in buf:
                break
            continue
    sock.close()
    # strip terminal control chars roughly and the echoed command
    text = buf.decode("utf-8", "replace")
    text = text.replace(marker, "")
    lines = [l for l in text.split("\r\n")]
    return "\n".join(lines)


if __name__ == "__main__":
    print(run_cmd(sys.argv[1]))