"""Exercise device registration/heartbeat/command receipts without controlling real hardware."""
import argparse
import getpass
import json
import os
import time
from urllib.request import Request, urlopen
from urllib.error import HTTPError


def main():
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument('--server', default='http://127.0.0.1:8088')
    parser.add_argument('--sn', required=True)
    args = parser.parse_args()
    server = args.server.rstrip('/')
    token = ''

    def request(path, body=None):
        headers = {'Content-Type': 'application/json'}
        if token:
            headers['Authorization'] = 'Bearer ' + token
        req = Request(server + path, data=json.dumps(body).encode() if body is not None else None, headers=headers)
        try:
            with urlopen(req, timeout=15) as response:
                return json.load(response)
        except HTTPError as error:
            detail = json.load(error)
            raise RuntimeError(detail.get('message', 'API request failed')) from None

    if request('/healthz').get('mode') != 'demo':
        raise SystemExit('This simulator only runs against VDI_MODE=demo.')
    secret = os.environ.get('VDI_DEVICE_ACTIVATION_SECRET') or getpass.getpass('One-time activation secret: ')
    result = request('/api/v1/terminal/register', {'sn': args.sn, 'activationSecret': secret, 'agentVersion': 'simulator-0.1'})
    token = result['accessToken']
    print('Registered terminal:', result['terminalId'])
    print('Simulator sends heartbeat only; all requested device operations return failed.')
    print('Press Ctrl+C to stop. No reboot, session change, or log collection is performed.')
    while True:
        request('/api/v1/terminal/heartbeat', {'agentVersion': 'simulator-0.1', 'fps': None, 'rtt': None})
        desktops = request('/api/v1/terminal/desktops')['items']
        print('Authorized desktops:', ', '.join(d['name'] for d in desktops) or '(none)')
        for command in request('/api/v1/terminal/commands')['items']:
            request('/api/v1/terminal/commands/' + command['id'] + '/ack', {'status': 'failed', 'message': 'Device simulator does not execute operations'})
            print('Returned failed receipt for:', command['action'], command['id'])
        time.sleep(10)


if __name__ == '__main__':
    try:
        main()
    except KeyboardInterrupt:
        print('\nSimulator stopped.')