from flask import Flask, request, jsonify, abort
import requests
import os

app = Flask(__name__)

# Optional token for access control (not production secure)
HEALTH_TOKEN = os.environ.get('HEALTH_TOKEN')

@app.route('/healthcheck')
def healthcheck():
    token = request.args.get('token') or request.headers.get('X-Health-Token')
    if HEALTH_TOKEN and token != HEALTH_TOKEN:
        return jsonify({'error': 'Unauthorized'}), 401

    host = request.args.get('host')
    port = request.args.get('port')
    proto = request.args.get('proto', 'http')
    if not host or not port:
        return jsonify({'error': 'missing parameters, expected host and port'}), 400

    url = f"{proto}://{host}:{port}"

    try:
        # Use HEAD to do a lightweight check
        r = requests.head(url, timeout=4, allow_redirects=True, verify=False)
        # Any 2xx/3xx is considered OK
        ok = 200 <= r.status_code < 400
        return jsonify({'ok': ok, 'status_code': r.status_code}), (200 if ok else 502)
    except requests.RequestException as e:
        return jsonify({'ok': False, 'error': str(e)}), 502

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=8081)