# Copyright (C) 2010 Chris Jerdonek (cjerdonek@webkit.org)
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1.  Redistributions of source code must retain the above copyright
#     notice, this list of conditions and the following disclaimer.
# 2.  Redistributions in binary form must reproduce the above copyright
#     notice, this list of conditions and the following disclaimer in the
#     documentation and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND
# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR
# ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

import logging
import unittest

from webkitpy.common.system.log_testing import TestLogStream
from webkitpy.common.system.log_utils import configure_logging


class ConfigureLoggingTestBase(unittest.TestCase):
    """Base class for configure_logging() unit tests."""

    def _logging_level(self):
        raise Exception('Not implemented.')

    def setUp(self):
        log_stream = TestLogStream(self)

        # Use a logger other than the root logger or one prefixed with
        # "webkitpy." so as not to conflict with test-webkitpy logging.
        logger = logging.getLogger('unittest')

        # Configure the test logger not to pass messages along to the
        # root logger.  This prevents test messages from being
        # propagated to loggers used by test-webkitpy logging (e.g.
        # the root logger).
        logger.propagate = False

        logging_level = self._logging_level()
        self._handlers = configure_logging(logging_level=logging_level, logger=logger, stream=log_stream)
        self._log = logger
        self._log_stream = log_stream

    def tearDown(self):
        """Reset logging to its original state.

        This method ensures that the logging configuration set up
        for a unit test does not affect logging in other unit tests.
        """
        logger = self._log
        for handler in self._handlers:
            logger.removeHandler(handler)

    def _assert_log_messages(self, messages):
        """Assert that the logged messages equal the given messages."""
        self._log_stream.assertMessages(messages)


class ConfigureLoggingTest(ConfigureLoggingTestBase):

    """Tests configure_logging() with the default logging level."""

    def _logging_level(self):
        return None

    def test_info_message(self):
        self._log.info('test message')
        self._assert_log_messages(['test message\n'])

    def test_debug_message(self):
        self._log.debug('test message')
        self._assert_log_messages([])

    def test_below_threshold_message(self):
        # We test the boundary case of a logging level equal to 19.
        # In practice, we will probably only be calling log.debug(),
        # which corresponds to a logging level of 10.
        level = logging.INFO - 1  # Equals 19.
        self._log.log(level, 'test message')
        self._assert_log_messages([])

    def test_two_messages(self):
        self._log.info('message1')
        self._log.info('message2')
        self._assert_log_messages(['message1\n',
                                   'message2\n'])


class ConfigureLoggingVerboseTest(ConfigureLoggingTestBase):

    def _logging_level(self):
        return logging.DEBUG

    def test_info_message(self):
        self._log.info('test message')
        self._assert_log_messages(['unittest: [INFO] test message\n'])

    def test_debug_message(self):
        self._log.debug('test message')
        self._assert_log_messages(['unittest: [DEBUG] test message\n'])


class ConfigureLoggingCustomLevelTest(ConfigureLoggingTestBase):

    """Tests configure_logging() with a custom logging level."""

    _level = 36

    def _logging_level(self):
        return self._level

    def test_logged_message(self):
        self._log.log(self._level, 'test message')
        self._assert_log_messages(['test message\n'])

    def test_below_threshold_message(self):
        self._log.log(self._level - 1, 'test message')
        self._assert_log_messages([])