import sys
import unittest
from fpsweeper.connector import mysql
from fpsweeper import config
from fpsweeper.logic import sweeper


class TestSweeperMissingTuids(unittest.TestCase):
    def exit_if_not_test_environment(self):
        """For safety, only run tests in test environment pointed to sqlite
        Exit immediately if not in test environment or not pointed to sqlite
        """
        if config.environment != config.TEST_ENVIRONMENT:
            sys.exit("Environment must be set to {}".format(config.TEST_ENVIRONMENT))
        elif 'sqlite' not in self.test_db_session.bind.url.drivername:
            sys.exit("Tests must point to sqlite database")

    def setUp(self):
        """Create test db tables with some simple fixture data
        """

        self.test_db_session = mysql.fpc_session()
        self.exit_if_not_test_environment()
        self.test_db_session.execute("CREATE TABLE track_fp(tuid INT NOT NULL)")
        self.populate_test_tables()

    def populate_test_tables(self):
        """Insert some simple fixture data into the fingerprint_capture test table
        track_fp will contain tuids 1, 2, 3
        """

        self.exit_if_not_test_environment()
        for i in range(1, 4):
            self.test_db_session.execute("INSERT INTO track_fp(tuid) VALUES ({})".format(i))

    def tearDown(self):
        """Tear down the test db tables
        """

        self.exit_if_not_test_environment()
        self.test_db_session.execute("DROP TABLE track_fp")

    def test_empty_expected_tuids(self):
        """Assert that passing in empty set of expected_tuids returns
        another empty set.
        """

        expected_tuids = frozenset([])
        missing_tuids = sweeper.get_missing_tuids(self.test_db_session, expected_tuids)
        self.assertEqual(len(missing_tuids), 0)

    def test_no_missing_tuids(self):
        """Assert that passing in set of tuids that are all in fp db returns
        an empty set."""

        expected_uids = frozenset([1, 2, 3])
        missing_tuids = sweeper.get_missing_tuids(self.test_db_session, expected_uids)
        self.assertEqual(len(missing_tuids), 0)

    def test_some_missing_tuids(self):
        """Assert that passing in set of tuids where some of the tuids are missing
        in the fp db returns the set of missing uids"""

        expected_uids = frozenset([1, 2, 3, 4, 5, 6, 7, 8, 9])
        missing_tuids = sweeper.get_missing_tuids(self.test_db_session, expected_uids)
        self.assertEqual(missing_tuids, frozenset([4, 5, 6, 7, 8, 9]))