import logging
import json

from flask import request, Blueprint, abort, Response
from flask_login import current_user

from app import userevents
from auth.decorators import require_session_login
from data.userevent import CannotReadUserEventsException


logger = logging.getLogger(__name__)


realtime = Blueprint('realtime', __name__)


@realtime.route("/user/")
@require_session_login
def index():
  debug_template = """
    <html>
      <head>
      </head>
      <body>
        <h1>Server sent events</h1>
        <div id="event"></div>
        <script type="text/javascript">

        var eventOutputContainer = document.getElementById("event");
        var evtSrc = new EventSource("/realtime/user/subscribe?events=docker-cli");

        evtSrc.onmessage = function(e) {
            console.log(e.data);
            eventOutputContainer.innerHTML = e.data;
        };

        </script>
      </body>
    </html>
    """
  return(debug_template)


@realtime.route("/user/test")
@require_session_login
def user_test():
  evt = userevents.get_event(current_user.db_user().username)
  evt.publish_event_data('test', {'foo': 2})
  return 'OK'

@realtime.route("/user/subscribe")
@require_session_login
def user_subscribe():
  def wrapper(listener):
    yield 'data: %s\n\n' % json.dumps({})

    for event_id, data in listener.event_stream():
      message = {'event': event_id, 'data': data}
      json_string = json.dumps(message)
      yield 'data: %s\n\n' % json_string

  events = request.args.get('events', '').split(',')
  if not events:
    abort(404)

  try:
    listener = userevents.get_listener(current_user.db_user().username, events)
  except CannotReadUserEventsException:
    abort(504)

  return Response(wrapper(listener), mimetype="text/event-stream")