<reponame>szymonlipinski/nativepython
#   Copyright 2017-2019 Nativepython Authors
#
#   Licensed under the Apache License, Version 2.0 (the "License");
#   you may not use this file except in compliance with the License.
#   You may obtain a copy of the License at
#
#       http://www.apache.org/licenses/LICENSE-2.0
#
#   Unless required by applicable law or agreed to in writing, software
#   distributed under the License is distributed on an "AS IS" BASIS,
#   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#   See the License for the specific language governing permissions and
#   limitations under the License.

import time

from object_database.web.cells import Cells


def waitForCellsCondition(cells: Cells, condition, timeout=10.0):
    assert cells.db.serializationContext is not None

    t0 = time.time()
    while time.time() - t0 < timeout:
        condRes = condition()

        if not condRes:
            time.sleep(.1)
            cells.renderMessages()
        else:
            return condRes

    exceptions = cells.childrenWithExceptions()
    if exceptions:
        raise Exception("\n\n".join([e.childByIndex(0).contents for e in exceptions]))

    return None
