# Copyright 2020 ScyllaDB
#
# This file is part of Scylla.
#
# Scylla is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Scylla is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with Scylla.  If not, see <http://www.gnu.org/licenses/>.

# This file configures pytest for all tests in this directory, and also
# defines common test fixtures for all of them to use. A "fixture" is some
# setup which an invididual test requires to run; The fixture has setup code
# and teardown code, and if multiple tests require the same fixture, it can
# be set up only once - while still allowing the user to run individual tests
# and automatically setting up the fixtures they need.

import pytest

from cassandra.cluster import Cluster, ConsistencyLevel, ExecutionProfile, EXEC_PROFILE_DEFAULT
from cassandra.policies import RoundRobinPolicy

from util import unique_name, new_test_table

# By default, tests run against a CQL server (Scylla or Cassandra) listening
# on localhost:9042. Add the --host and --port options to allow overiding
# these defaults.
def pytest_addoption(parser):
    parser.addoption('--host', action='store', default='localhost',
        help='CQL server host to connect to')
    parser.addoption('--port', action='store', default='9042',
        help='CQL server port to connect to')

# "cql" fixture: set up client object for communicating with the CQL API.
# The host/port combination of the server are determined by the --host and
# --port options, and defaults to localhost and 9042, respectively.
# We use scope="session" so that all tests will reuse the same client object.
@pytest.fixture(scope="session")
def cql(request):
    profile = ExecutionProfile(
        load_balancing_policy=RoundRobinPolicy(),
        consistency_level=ConsistencyLevel.LOCAL_QUORUM,
        serial_consistency_level=ConsistencyLevel.LOCAL_SERIAL,
        # The default timeout (in seconds) for execute() commands is 10, which
        # should have been more than enough, but in some extreme cases with a
        # very slow debug build running on a very busy machine and a very slow
        # request (e.g., a DROP KEYSPACE needing to drop multiple tables)
        # 10 seconds may not be enough, so let's increase it. See issue #7838.
        request_timeout = 120)
    cluster = Cluster(execution_profiles={EXEC_PROFILE_DEFAULT: profile},
        contact_points=[request.config.getoption('host')],
        port=request.config.getoption('port'),
        # TODO: make the protocol version an option, to allow testing with
        # different versions. If we drop this setting completely, it will
        # mean pick the latest version supported by the client and the server.
        protocol_version=4
    )
    return cluster.connect()

# "test_keyspace" fixture: Creates and returns a temporary keyspace to be
# used in tests that need a keyspace. The keyspace is created with RF=1,
# and automatically deleted at the end. We use scope="session" so that all
# tests will reuse the same keyspace.
@pytest.fixture(scope="session")
def test_keyspace(cql):
    name = unique_name()
    cql.execute("CREATE KEYSPACE " + name + " WITH REPLICATION = { 'class' : 'SimpleStrategy', 'replication_factor' : 1 }")
    yield name
    cql.execute("DROP KEYSPACE " + name)

# The "scylla_only" fixture can be used by tests for Scylla-only features,
# which do not exist on Apache Cassandra. A test using this fixture will be
# skipped if running with "run-cassandra".
@pytest.fixture(scope="session")
def scylla_only(cql):
    # We recognize Scylla by checking if there is any system table whose name
    # contains the word "scylla":
    names = [row.table_name for row in cql.execute("SELECT * FROM system_schema.tables WHERE keyspace_name = 'system'")]
    if not any('scylla' in name for name in names):
        pytest.skip('Scylla-only test skipped')

# TODO: use new_test_table and "yield from" to make shared test_table
# fixtures with some common schemas.
