#!/usr/bin/env python3
"""Proxmox-side fail-closed monitor; only the disposable VM223 is stopped."""
import json
import pathlib
import shutil
import subprocess
import time

DIRECTORY = pathlib.Path('/var/lib/vz/honeypot')


def qm(*args):
    return subprocess.run(['/usr/sbin/qm', *args], capture_output=True, text=True, timeout=25, check=True).stdout


def stop(reason):
    with (DIRECTORY / 'watchdog-events.jsonl').open('a') as output:
        output.write(json.dumps(dict(time_ns=time.time_ns(), event='execution_vm_stopped', reason=reason)) + '\n')
        output.flush()
    qm('stop', '223')
    # This latch prevents unattended auto-restart. Operator must verify evidence before clearing.
    (DIRECTORY / 'STOP').touch(mode=0o600)


def main():
    last_health = 0
    while True:
        try:
            if 'status: running' not in qm('status', '223'):
                time.sleep(2)
                continue
            reason = None
            pcap = DIRECTORY / 'execution.pcap'
            if (DIRECTORY / 'STOP').exists():
                reason = 'host stop latch'
            elif pcap.exists() and pcap.stat().st_size >= 512 * 1024 * 1024:
                reason = 'pcap quota'
            elif shutil.disk_usage(DIRECTORY).free < 4 * 1024**3:
                reason = 'host free space reserve'
            elif time.monotonic() - last_health >= 10:
                last_health = time.monotonic()
                usage = subprocess.run(['/usr/sbin/lvs', '--noheadings', '-o', 'data_percent', 'pve/data'], capture_output=True, text=True, check=True, timeout=5)
                if float(usage.stdout.strip()) >= 85:
                    stop('Proxmox thin pool reserve')
                    continue
                try:
                    result = json.loads(qm('guest', 'exec', '222', '--timeout', '10', '--',
                        '/bin/sh', '-c',
                        'test ! -e /var/lib/decoy/STOP && '
                        'systemctl is-active --quiet decoy.service decoy-network.service'))
                    if result.get('exitcode') != 0 or not result.get('exited'):
                        reason = 'collector services stopped or capture failed'
                except (OSError, ValueError, subprocess.SubprocessError):
                    reason = 'collector health unavailable'
            if reason:
                stop(reason)
        except (OSError, subprocess.SubprocessError) as error:
            print(type(error).__name__, flush=True)
        time.sleep(1)


if __name__ == '__main__':
    main()