import datetime
import json

from contextlib import contextmanager

from data import model
from endpoints.api import api

CSRF_TOKEN_KEY = '_csrf_token'
CSRF_TOKEN = '123csrfforme'


@contextmanager
def client_with_identity(auth_username, client):
  with client.session_transaction() as sess:
    if auth_username:
      if auth_username is not None:
        loaded = model.user.get_user(auth_username)
        sess['user_id'] = loaded.uuid
        sess['login_time'] = datetime.datetime.now()
        sess[CSRF_TOKEN_KEY] = CSRF_TOKEN

  yield client

  with client.session_transaction() as sess:
    sess['user_id'] = None
    sess['login_time'] = None
    sess[CSRF_TOKEN_KEY] = None


def add_csrf_param(params):
  """ Returns a params dict with the CSRF parameter added. """
  params = params or {}
  params[CSRF_TOKEN_KEY] = CSRF_TOKEN
  return params


def conduct_api_call(client, resource, method, params, body=None, expected_code=200):
  """ Conducts an API call to the given resource via the given client, and ensures its returned
      status matches the code given.

      Returns the response.
  """
  params = add_csrf_param(params)

  final_url = api.url_for(resource, **params)

  headers = {}
  headers.update({"Content-Type": "application/json"})

  if body is not None:
    body = json.dumps(body)

  rv = client.open(final_url, method=method, data=body, headers=headers)
  msg = '%s %s: got %s expected: %s | %s' % (method, final_url, rv.status_code, expected_code,
                                             rv.data)
  assert rv.status_code == expected_code, msg
  return rv