# Copyright 2013 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

import Queue
import datetime
import logging
import os
import shutil
import signal
import sys
import tempfile
import time
import unittest

import mox

import common
import gs_offloader
import job_directories

from autotest_lib.client.common_lib import utils, time_utils
from autotest_lib.client.common_lib import global_config
from autotest_lib.scheduler import email_manager


# Test value to use for `days_old`, if nothing else is required.
_TEST_EXPIRATION_AGE = 7

# When constructing sample time values for testing expiration,
# allow this many seconds between the expiration time and the
# current time.
_MARGIN_SECS = 10.0


def _get_options(argv):
    """Helper function to exercise command line parsing.

    @param argv Value of sys.argv to be parsed.

    """
    sys.argv = ['bogus.py'] + argv
    return gs_offloader.parse_options()


class OffloaderOptionsTests(mox.MoxTestBase):
    """Tests for the `Offloader` constructor.

    Tests that offloader instance fields are set as expected
    for given command line options.

    """

    _REGULAR_ONLY = set([job_directories.RegularJobDirectory])
    _SPECIAL_ONLY = set([job_directories.SpecialJobDirectory])
    _BOTH = _REGULAR_ONLY | _SPECIAL_ONLY


    def setUp(self):
        super(OffloaderOptionsTests, self).setUp()
        self.mox.StubOutWithMock(utils, 'get_offload_gsuri')
        gs_offloader.GS_OFFLOADING_ENABLED = True


    def _mock_get_offload_func(self, is_moblab):
        """Mock the process of getting the offload_dir function."""
        if is_moblab:
            expected_gsuri = '%sresults/%s/%s/' % (
                    global_config.global_config.get_config_value(
                            'CROS', 'image_storage_server'),
                    'Fa:ke:ma:c0:12:34', 'rand0m-uu1d')
        else:
            expected_gsuri = utils.DEFAULT_OFFLOAD_GSURI
        utils.get_offload_gsuri().AndReturn(expected_gsuri)
        offload_func = gs_offloader.get_offload_dir_func(expected_gsuri)
        self.mox.StubOutWithMock(gs_offloader, 'get_offload_dir_func')
        gs_offloader.get_offload_dir_func(expected_gsuri).AndReturn(
                offload_func)
        self.mox.ReplayAll()
        return offload_func


    def test_process_no_options(self):
        """Test default offloader options."""
        offload_func = self._mock_get_offload_func(False)
        offloader = gs_offloader.Offloader(_get_options([]))
        self.assertEqual(set(offloader._jobdir_classes),
                         self._REGULAR_ONLY)
        self.assertEqual(offloader._processes, 1)
        self.assertEqual(offloader._offload_func,
                         offload_func)
        self.assertEqual(offloader._age_limit, 0)


    def test_process_all_option(self):
        """Test offloader handling for the --all option."""
        offload_func = self._mock_get_offload_func(False)
        offloader = gs_offloader.Offloader(_get_options(['--all']))
        self.assertEqual(set(offloader._jobdir_classes), self._BOTH)
        self.assertEqual(offloader._processes, 1)
        self.assertEqual(offloader._offload_func,
                         offload_func)
        self.assertEqual(offloader._age_limit, 0)


    def test_process_hosts_option(self):
        """Test offloader handling for the --hosts option."""
        offload_func = self._mock_get_offload_func(False)
        offloader = gs_offloader.Offloader(
                _get_options(['--hosts']))
        self.assertEqual(set(offloader._jobdir_classes),
                         self._SPECIAL_ONLY)
        self.assertEqual(offloader._processes, 1)
        self.assertEqual(offloader._offload_func,
                         offload_func)
        self.assertEqual(offloader._age_limit, 0)


    def test_parallelism_option(self):
        """Test offloader handling for the --parallelism option."""
        offload_func = self._mock_get_offload_func(False)
        offloader = gs_offloader.Offloader(
                _get_options(['--parallelism', '2']))
        self.assertEqual(set(offloader._jobdir_classes),
                         self._REGULAR_ONLY)
        self.assertEqual(offloader._processes, 2)
        self.assertEqual(offloader._offload_func,
                         offload_func)
        self.assertEqual(offloader._age_limit, 0)


    def test_delete_only_option(self):
        """Test offloader handling for the --delete_only option."""
        offloader = gs_offloader.Offloader(
                _get_options(['--delete_only']))
        self.assertEqual(set(offloader._jobdir_classes),
                         self._REGULAR_ONLY)
        self.assertEqual(offloader._processes, 1)
        self.assertEqual(offloader._offload_func,
                         gs_offloader.delete_files)
        self.assertEqual(offloader._age_limit, 0)


    def test_days_old_option(self):
        """Test offloader handling for the --days_old option."""
        offload_func = self._mock_get_offload_func(False)
        offloader = gs_offloader.Offloader(
                _get_options(['--days_old', '7']))
        self.assertEqual(set(offloader._jobdir_classes),
                         self._REGULAR_ONLY)
        self.assertEqual(offloader._processes, 1)
        self.assertEqual(offloader._offload_func,
                         offload_func)
        self.assertEqual(offloader._age_limit, 7)


    def test_moblab_gsuri_generation(self):
        """Test offloader construction for Moblab."""
        offload_func = self._mock_get_offload_func(True)
        offloader = gs_offloader.Offloader(_get_options([]))
        self.assertEqual(set(offloader._jobdir_classes),
                         self._REGULAR_ONLY)
        self.assertEqual(offloader._processes, 1)
        self.assertEqual(offloader._offload_func,
                         offload_func)
        self.assertEqual(offloader._age_limit, 0)


    def test_globalconfig_offloading_flag(self):
        """Test enabling of --delete_only via global_config."""
        gs_offloader.GS_OFFLOADING_ENABLED = False
        offloader = gs_offloader.Offloader(
                _get_options([]))
        self.assertEqual(offloader._offload_func,
                         gs_offloader.delete_files)


def _make_timestamp(age_limit, is_expired):
    """Create a timestamp for use by `job_directories._is_job_expired()`.

    The timestamp will meet the syntactic requirements for
    timestamps used as input to `_is_job_expired()`.  If
    `is_expired` is true, the timestamp will be older than
    `age_limit` days before the current time; otherwise, the
    date will be younger.

    @param age_limit    The number of days before expiration of the
                        target timestamp.
    @param is_expired   Whether the timestamp should be expired
                        relative to `age_limit`.

    """
    seconds = -_MARGIN_SECS
    if is_expired:
        seconds = -seconds
    delta = datetime.timedelta(days=age_limit, seconds=seconds)
    reference_time = datetime.datetime.now() - delta
    return reference_time.strftime(time_utils.TIME_FMT)


class JobExpirationTests(unittest.TestCase):
    """Tests to exercise `job_directories._is_job_expired()`."""

    def test_expired(self):
        """Test detection of an expired job."""
        timestamp = _make_timestamp(_TEST_EXPIRATION_AGE, True)
        self.assertTrue(
            job_directories._is_job_expired(
                _TEST_EXPIRATION_AGE, timestamp))


    def test_alive(self):
        """Test detection of a job that's not expired."""
        # N.B.  This test may fail if its run time exceeds more than
        # about _MARGIN_SECS seconds.
        timestamp = _make_timestamp(_TEST_EXPIRATION_AGE, False)
        self.assertFalse(
            job_directories._is_job_expired(
                _TEST_EXPIRATION_AGE, timestamp))


class _MockJobDirectory(job_directories._JobDirectory):
    """Subclass of `_JobDirectory` used as a helper for tests."""

    GLOB_PATTERN = '[0-9]*-*'


    def __init__(self, resultsdir):
        """Create new job in initial state."""
        super(_MockJobDirectory, self).__init__(resultsdir)
        self._timestamp = None
        self.queue_args = [resultsdir, os.path.dirname(resultsdir)]


    def get_timestamp_if_finished(self):
        return self._timestamp


    def set_finished(self, days_old):
        """Make this job appear to be finished.

        After calling this function, calls to `enqueue_offload()`
        will find this job as finished, but not expired and ready
        for offload.  Note that when `days_old` is 0,
        `enqueue_offload()` will treat a finished job as eligible
        for offload.

        @param days_old The value of the `days_old` parameter that
                        will be passed to `enqueue_offload()` for
                        testing.

        """
        self._timestamp = _make_timestamp(days_old, False)


    def set_expired(self, days_old):
        """Make this job eligible to be offloaded.

        After calling this function, calls to `offload` will attempt
        to offload this job.

        @param days_old The value of the `days_old` parameter that
                        will be passed to `enqueue_offload()` for
                        testing.

        """
        self._timestamp = _make_timestamp(days_old, True)


    def set_incomplete(self):
        """Make this job appear to have failed offload just once."""
        self._offload_count += 1
        self._first_offload_start = time.time()
        if not os.path.isdir(self._dirname):
            os.mkdir(self._dirname)


    def set_reportable(self):
        """Make this job be reportable."""
        self.set_incomplete()
        self._offload_count += 1


    def set_complete(self):
        """Make this job be completed."""
        self._offload_count += 1
        if os.path.isdir(self._dirname):
            os.rmdir(self._dirname)


class CommandListTests(unittest.TestCase):
    """Tests for `get_cmd_list()`."""

    def _command_list_assertions(self, job, use_rsync=True):
        """Call `get_cmd_list()` and check the return value.

        Check the following assertions:
          * The command name (argv[0]) is 'gsutil'.
          * The arguments contain the 'cp' subcommand.
          * The next-to-last argument (the source directory) is the
            job's `queue_args[0]`.
          * The last argument (the destination URL) is the job's
            'queue_args[1]'.

        @param job A job with properly calculated arguments to
                   `get_cmd_list()`

        """
        test_bucket_uri = 'gs://a-test-bucket'

        gs_offloader.USE_RSYNC_ENABLED = use_rsync

        command = gs_offloader.get_cmd_list(
            job.queue_args[0],
            os.path.join(test_bucket_uri, job.queue_args[1]))

        self.assertEqual(command[0], 'gsutil')
        self.assertEqual(command[-2], job.queue_args[0])

        if use_rsync:
            self.assertTrue('rsync' in command)
            self.assertEqual(command[-1],
                             os.path.join(test_bucket_uri, job.queue_args[0]))
        else:
            self.assertTrue('cp' in command)
            self.assertEqual(command[-1],
                             os.path.join(test_bucket_uri, job.queue_args[1]))


    def test_get_cmd_list_regular(self):
        """Test `get_cmd_list()` as for a regular job."""
        job = _MockJobDirectory('118-debug')
        self._command_list_assertions(job)


    def test_get_cmd_list_special(self):
        """Test `get_cmd_list()` as for a special job."""
        job = _MockJobDirectory('hosts/host1/118-reset')
        self._command_list_assertions(job)


    def test_get_cmd_list_regular_no_rsync(self):
        """Test `get_cmd_list()` as for a regular job."""
        job = _MockJobDirectory('118-debug')
        self._command_list_assertions(job, use_rsync=False)


    def test_get_cmd_list_special_no_rsync(self):
        """Test `get_cmd_list()` as for a special job."""
        job = _MockJobDirectory('hosts/host1/118-reset')
        self._command_list_assertions(job, use_rsync=False)


# Below is partial sample of e-mail notification text.  This text is
# deliberately hard-coded and then parsed to create the test data;
# the idea is to make sure the actual text format will be reviewed
# by a human being.
#
# first offload      count  directory
# --+----1----+----  ----+  ----+----1----+----2----+----3
_SAMPLE_DIRECTORIES_REPORT = '''\
=================== ======  ==============================
2014-03-14 15:09:26      1  118-fubar
2014-03-14 15:19:23      2  117-fubar
2014-03-14 15:29:20      6  116-fubar
2014-03-14 15:39:17     24  115-fubar
2014-03-14 15:49:14    120  114-fubar
2014-03-14 15:59:11    720  113-fubar
2014-03-14 16:09:08   5040  112-fubar
2014-03-14 16:19:05  40320  111-fubar
'''


class EmailTemplateTests(mox.MoxTestBase):
    """Test the formatting of e-mail notifications."""

    def setUp(self):
        super(EmailTemplateTests, self).setUp()
        self.mox.StubOutWithMock(email_manager.manager,
                                 'send_email')
        self._joblist = []
        for line in _SAMPLE_DIRECTORIES_REPORT.split('\n')[1 : -1]:
            date_, time_, count, dir_ = line.split()
            job = _MockJobDirectory(dir_)
            job._offload_count = int(count)
            timestruct = time.strptime("%s %s" % (date_, time_),
                                       gs_offloader.ERROR_EMAIL_TIME_FORMAT)
            job._first_offload_start = time.mktime(timestruct)
            # enter the jobs in reverse order, to make sure we
            # test that the output will be sorted.
            self._joblist.insert(0, job)


    def test_email_template(self):
        """Trigger an e-mail report and check its contents."""
        # The last line of the report is a separator that we
        # repeat in the first line of our expected result data.
        # So, we remove that separator from the end of the of
        # the e-mail report message.
        #
        # The last element in the list returned by split('\n')
        # will be an empty string, so to remove the separator,
        # we remove the next-to-last entry in the list.
        report_lines = gs_offloader.ERROR_EMAIL_REPORT_FORMAT.split('\n')
        expected_message = ('\n'.join(report_lines[: -2] +
                                      report_lines[-1 :]) +
                            _SAMPLE_DIRECTORIES_REPORT)
        email_manager.manager.send_email(
            mox.IgnoreArg(), mox.IgnoreArg(), expected_message)
        self.mox.ReplayAll()
        gs_offloader.report_offload_failures(self._joblist)


class JobDirectorySubclassTests(mox.MoxTestBase):
    """Test specific to RegularJobDirectory and SpecialJobDirectory.

    This provides coverage for the implementation in both
    RegularJobDirectory and SpecialJobDirectory.

    """

    def setUp(self):
        super(JobDirectorySubclassTests, self).setUp()
        self.mox.StubOutWithMock(job_directories._AFE, 'run')


    def test_regular_job_fields(self):
        """Test the constructor for `RegularJobDirectory`.

        Construct a regular job, and assert that the `_dirname`
        and `_id` attributes are set as expected.

        """
        resultsdir = '118-fubar'
        job = job_directories.RegularJobDirectory(resultsdir)
        self.assertEqual(job._dirname, resultsdir)
        self.assertEqual(job._id, 118)


    def test_special_job_fields(self):
        """Test the constructor for `SpecialJobDirectory`.

        Construct a special job, and assert that the `_dirname`
        and `_id` attributes are set as expected.

        """
        destdir = 'hosts/host1'
        resultsdir = destdir + '/118-reset'
        job = job_directories.SpecialJobDirectory(resultsdir)
        self.assertEqual(job._dirname, resultsdir)
        self.assertEqual(job._id, 118)


    def test_finished_regular_job(self):
        """Test getting the timestamp for a finished regular job.

        Tests the return value for
        `RegularJobDirectory.get_timestamp_if_finished()` when
        the AFE indicates the job is finished.

        """
        job = job_directories.RegularJobDirectory('118-fubar')
        timestamp = _make_timestamp(0, True)
        job_directories._AFE.run(
            'get_jobs', id=job._id, finished=True).AndReturn(
                [{'created_on': _make_timestamp(0, True)}])
        job_directories._AFE.run(
            'get_host_queue_entries', finished_on__isnull=False,
            job_id=job._id).AndReturn(
                [{'finished_on': timestamp}])
        self.mox.ReplayAll()
        self.assertEqual(timestamp,
                         job.get_timestamp_if_finished())


    def test_finished_regular_job_multiple_hqes(self):
        """Test getting the timestamp for a regular job with multiple hqes.

        Tests the return value for
        `RegularJobDirectory.get_timestamp_if_finished()` when
        the AFE indicates the job is finished and the job has multiple host
        queue entries.

        If there is more than one HQE, this test guarantees latest timestamp is
        the one returned.
        """
        job = job_directories.RegularJobDirectory('118-fubar')
        created_timestamp = _make_timestamp(2, True)
        older_hqe_timestamp = _make_timestamp(1, True)
        newer_hqe_timestamp = _make_timestamp(0, True)
        job_directories._AFE.run(
            'get_jobs', id=job._id, finished=True).AndReturn(
                [{'created_on': created_timestamp}])
        job_directories._AFE.run(
            'get_host_queue_entries', finished_on__isnull=False,
            job_id=job._id).AndReturn(
                [{'finished_on': older_hqe_timestamp},
                 {'finished_on': newer_hqe_timestamp}])
        # For the second call return the latest hqe last.
        job_directories._AFE.run(
            'get_jobs', id=job._id, finished=True).AndReturn(
                [{'created_on': created_timestamp}])
        job_directories._AFE.run(
            'get_host_queue_entries', finished_on__isnull=False,
            job_id=job._id).AndReturn(
                [{'finished_on': newer_hqe_timestamp},
                 {'finished_on': older_hqe_timestamp}])
        self.mox.ReplayAll()
        self.assertEqual(newer_hqe_timestamp,
                         job.get_timestamp_if_finished())
        self.assertEqual(newer_hqe_timestamp,
                         job.get_timestamp_if_finished())


    def test_finished_regular_job_null_finished_times(self):
        """Test getting the timestamp for an aborted regular job.

        Tests the return value for
        `RegularJobDirectory.get_timestamp_if_finished()` when
        the AFE indicates the job is finished and the job has aborted host
        queue entries.

        """
        job = job_directories.RegularJobDirectory('118-fubar')
        timestamp = _make_timestamp(0, True)
        job_directories._AFE.run(
            'get_jobs', id=job._id, finished=True).AndReturn(
                [{'created_on': timestamp}])
        job_directories._AFE.run(
            'get_host_queue_entries', finished_on__isnull=False,
            job_id=job._id).AndReturn([])
        self.mox.ReplayAll()
        self.assertEqual(timestamp,
                         job.get_timestamp_if_finished())


    def test_unfinished_regular_job(self):
        """Test getting the timestamp for an unfinished regular job.

        Tests the return value for
        `RegularJobDirectory.get_timestamp_if_finished()` when
        the AFE indicates the job is not finished.

        """
        job = job_directories.RegularJobDirectory('118-fubar')
        job_directories._AFE.run(
            'get_jobs', id=job._id, finished=True).AndReturn(None)
        self.mox.ReplayAll()
        self.assertIsNone(job.get_timestamp_if_finished())


    def test_finished_special_job(self):
        """Test getting the timestamp for a finished special job.

        Tests the return value for
        `SpecialJobDirectory.get_timestamp_if_finished()` when
        the AFE indicates the job is finished.

        """
        job = job_directories.SpecialJobDirectory(
                'hosts/host1/118-reset')
        timestamp = _make_timestamp(0, True)
        job_directories._AFE.run('get_special_tasks',
                                 id=job._id,
                                 is_complete=True).AndReturn(
                                     [{'time_finished': timestamp}])
        self.mox.ReplayAll()
        self.assertEqual(timestamp,
                         job.get_timestamp_if_finished())


    def test_unfinished_special_job(self):
        """Test getting the timestamp for an unfinished special job.

        Tests the return value for
        `SpecialJobDirectory.get_timestamp_if_finished()` when
        the AFE indicates the job is not finished.

        """
        job = job_directories.SpecialJobDirectory(
                'hosts/host1/118-reset')
        job_directories._AFE.run('get_special_tasks',
                                 id=job._id,
                                 is_complete=True).AndReturn(None)
        self.mox.ReplayAll()
        self.assertIsNone(job.get_timestamp_if_finished())


class _TempResultsDirTestBase(mox.MoxTestBase):
    """Base class for tests using a temporary results directory."""

    REGULAR_JOBLIST = [
        '111-fubar', '112-fubar', '113-fubar', '114-snafu']
    HOST_LIST = ['host1', 'host2', 'host3']
    SPECIAL_JOBLIST = [
        'hosts/host1/333-reset', 'hosts/host1/334-reset',
        'hosts/host2/444-reset', 'hosts/host3/555-reset']


    def setUp(self):
        super(_TempResultsDirTestBase, self).setUp()
        self._resultsroot = tempfile.mkdtemp()
        self._cwd = os.getcwd()
        os.chdir(self._resultsroot)


    def tearDown(self):
        os.chdir(self._cwd)
        shutil.rmtree(self._resultsroot)
        super(_TempResultsDirTestBase, self).tearDown()


    def make_job(self, jobdir):
        """Create a job with results in `self._resultsroot`.

        @param jobdir Name of the subdirectory to be created in
                      `self._resultsroot`.

        """
        os.mkdir(jobdir)
        return _MockJobDirectory(jobdir)


    def make_job_hierarchy(self):
        """Create a sample hierarchy of job directories.

        `self.REGULAR_JOBLIST` is a list of directories for regular
        jobs to be created; `self.SPECIAL_JOBLIST` is a list of
        directories for special jobs to be created.

        """
        for d in self.REGULAR_JOBLIST:
            os.mkdir(d)
        hostsdir = 'hosts'
        os.mkdir(hostsdir)
        for host in self.HOST_LIST:
            os.mkdir(os.path.join(hostsdir, host))
        for d in self.SPECIAL_JOBLIST:
            os.mkdir(d)


class OffloadDirectoryTests(_TempResultsDirTestBase):
    """Tests for `offload_dir()`."""

    def setUp(self):
        super(OffloadDirectoryTests, self).setUp()
        # offload_dir() logs messages; silence them.
        self._saved_loglevel = logging.getLogger().getEffectiveLevel()
        logging.getLogger().setLevel(logging.CRITICAL+1)
        self._job = self.make_job(self.REGULAR_JOBLIST[0])
        self.mox.StubOutWithMock(gs_offloader, 'get_cmd_list')
        self.mox.StubOutWithMock(signal, 'alarm')


    def tearDown(self):
        logging.getLogger().setLevel(self._saved_loglevel)
        super(OffloadDirectoryTests, self).tearDown()


    def _mock_offload_dir_calls(self, command, queue_args):
        """Mock out the calls needed by `offload_dir()`.

        This covers only the calls made when there is no timeout.

        @param command Command list to be returned by the mocked
                       call to `get_cmd_list()`.

        """
        signal.alarm(gs_offloader.OFFLOAD_TIMEOUT_SECS)
        command.append(queue_args[0])
        gs_offloader.get_cmd_list(
                queue_args[0], '%s%s' % (utils.DEFAULT_OFFLOAD_GSURI,
                                         queue_args[1])).AndReturn(
                        command)
        signal.alarm(0)
        signal.alarm(0)


    def _run_offload_dir(self, should_succeed):
        """Make one call to `offload_dir()`.

        The caller ensures all mocks are set up already.

        @param should_succeed True iff the call to `offload_dir()`
                              is expected to succeed and remove the
                              offloaded job directory.

        """
        self.mox.ReplayAll()
        gs_offloader.get_offload_dir_func(
                utils.DEFAULT_OFFLOAD_GSURI)(self._job.queue_args[0],
                                     self._job.queue_args[1])
        self.mox.VerifyAll()
        self.assertEqual(not should_succeed,
                         os.path.isdir(self._job.queue_args[0]))


    def test_offload_success(self):
        """Test that `offload_dir()` can succeed correctly."""
        self._mock_offload_dir_calls(['test', '-d'],
                                     self._job.queue_args)
        self._run_offload_dir(True)


    def test_offload_failure(self):
        """Test that `offload_dir()` can fail correctly."""
        self._mock_offload_dir_calls(['test', '!', '-d'],
                                     self._job.queue_args)
        self._run_offload_dir(False)


    def test_offload_timeout_early(self):
        """Test that `offload_dir()` times out correctly.

        This test triggers timeout at the earliest possible moment,
        at the first call to set the timeout alarm.

        """
        signal.alarm(gs_offloader.OFFLOAD_TIMEOUT_SECS).AndRaise(
                        gs_offloader.TimeoutException('fubar'))
        signal.alarm(0)
        self._run_offload_dir(False)


    def test_offload_timeout_late(self):
        """Test that `offload_dir()` times out correctly.

        This test triggers timeout at the latest possible moment, at
        the call to clear the timeout alarm.

        """
        signal.alarm(gs_offloader.OFFLOAD_TIMEOUT_SECS)
        gs_offloader.get_cmd_list(
                mox.IgnoreArg(), mox.IgnoreArg()).AndReturn(
                        ['test', '-d', self._job.queue_args[0]])
        signal.alarm(0).AndRaise(
                gs_offloader.TimeoutException('fubar'))
        signal.alarm(0)
        self._run_offload_dir(False)


class JobDirectoryOffloadTests(_TempResultsDirTestBase):
    """Tests for `_JobDirectory.enqueue_offload()`.

    When testing with a `days_old` parameter of 0, we use
    `set_finished()` instead of `set_expired()`.  This causes the
    job's timestamp to be set in the future.  This is done so as
    to test that when `days_old` is 0, the job is always treated
    as eligible for offload, regardless of the timestamp's value.

    Testing covers the following assertions:
     A. Each time `enqueue_offload()` is called, a message that
        includes the job's directory name will be logged using
        `logging.debug()`, regardless of whether the job was
        enqueued.  Nothing else is allowed to be logged.
     B. If the job is not eligible to be offloaded,
        `get_failure_time()` and `get_failure_count()` are 0.
     C. If the job is not eligible for offload, nothing is
        enqueued in `queue`.
     D. When the job is offloaded, `get_failure_count()` increments
        each time.
     E. When the job is offloaded, the appropriate parameters are
        enqueued exactly once.
     F. The first time a job is offloaded, `get_failure_time()` is
        set to the current time.
     G. `get_failure_time()` only changes the first time that the
        job is offloaded.

    The test cases below are designed to exercise all of the
    meaningful state transitions at least once.

    """

    def setUp(self):
        super(JobDirectoryOffloadTests, self).setUp()
        self._job = self.make_job(self.REGULAR_JOBLIST[0])
        self._queue = Queue.Queue()


    def _offload_unexpired_job(self, days_old):
        """Make calls to `enqueue_offload()` for an unexpired job.

        This method tests assertions B and C that calling
        `enqueue_offload()` has no effect.

        """
        self.assertEqual(self._job.get_failure_count(), 0)
        self.assertEqual(self._job.get_failure_time(), 0)
        self._job.enqueue_offload(self._queue, days_old)
        self._job.enqueue_offload(self._queue, days_old)
        self.assertTrue(self._queue.empty())
        self.assertEqual(self._job.get_failure_count(), 0)
        self.assertEqual(self._job.get_failure_time(), 0)
        self.assertFalse(self._job.is_reportable())


    def _offload_expired_once(self, days_old, count):
        """Make one call to `enqueue_offload()` for an expired job.

        This method tests assertions D and E regarding side-effects
        expected when a job is offloaded.

        """
        self._job.enqueue_offload(self._queue, days_old)
        self.assertEqual(self._job.get_failure_count(), count)
        self.assertFalse(self._queue.empty())
        v = self._queue.get_nowait()
        self.assertTrue(self._queue.empty())
        self.assertEqual(v, self._job.queue_args)


    def _offload_expired_job(self, days_old):
        """Make calls to `enqueue_offload()` for a just-expired job.

        This method directly tests assertions F and G regarding
        side-effects on `get_failure_time()`.

        """
        t0 = time.time()
        self._offload_expired_once(days_old, 1)
        self.assertFalse(self._job.is_reportable())
        t1 = self._job.get_failure_time()
        self.assertLessEqual(t1, time.time())
        self.assertGreaterEqual(t1, t0)
        self._offload_expired_once(days_old, 2)
        self.assertTrue(self._job.is_reportable())
        self.assertEqual(self._job.get_failure_time(), t1)
        self._offload_expired_once(days_old, 3)
        self.assertTrue(self._job.is_reportable())
        self.assertEqual(self._job.get_failure_time(), t1)


    def test_case_1_no_expiration(self):
        """Test a series of `enqueue_offload()` calls with `days_old` of 0.

        This tests that offload works as expected if calls are
        made both before and after the job becomes expired.

        """
        self._offload_unexpired_job(0)
        self._job.set_finished(0)
        self._offload_expired_job(0)


    def test_case_2_no_expiration(self):
        """Test a series of `enqueue_offload()` calls with `days_old` of 0.

        This tests that offload works as expected if calls are made
        only after the job becomes expired.

        """
        self._job.set_finished(0)
        self._offload_expired_job(0)


    def test_case_1_with_expiration(self):
        """Test a series of `enqueue_offload()` calls with `days_old` non-zero.

        This tests that offload works as expected if calls are made
        before the job finishes, before the job expires, and after
        the job expires.

        """
        self._offload_unexpired_job(_TEST_EXPIRATION_AGE)
        self._job.set_finished(_TEST_EXPIRATION_AGE)
        self._offload_unexpired_job(_TEST_EXPIRATION_AGE)
        self._job.set_expired(_TEST_EXPIRATION_AGE)
        self._offload_expired_job(_TEST_EXPIRATION_AGE)


    def test_case_2_with_expiration(self):
        """Test a series of `enqueue_offload()` calls with `days_old` non-zero.

        This tests that offload works as expected if calls are made
        between finishing and expiration, and after the job expires.

        """
        self._job.set_finished(_TEST_EXPIRATION_AGE)
        self._offload_unexpired_job(_TEST_EXPIRATION_AGE)
        self._job.set_expired(_TEST_EXPIRATION_AGE)
        self._offload_expired_job(_TEST_EXPIRATION_AGE)


    def test_case_3_with_expiration(self):
        """Test a series of `enqueue_offload()` calls with `days_old` non-zero.

        This tests that offload works as expected if calls are made
        only before finishing and after expiration.

        """
        self._offload_unexpired_job(_TEST_EXPIRATION_AGE)
        self._job.set_expired(_TEST_EXPIRATION_AGE)
        self._offload_expired_job(_TEST_EXPIRATION_AGE)


    def test_case_4_with_expiration(self):
        """Test a series of `enqueue_offload()` calls with `days_old` non-zero.

        This tests that offload works as expected if calls are made
        only after expiration.

        """
        self._job.set_expired(_TEST_EXPIRATION_AGE)
        self._offload_expired_job(_TEST_EXPIRATION_AGE)


class GetJobDirectoriesTests(_TempResultsDirTestBase):
    """Tests for `_JobDirectory.get_job_directories()`."""

    def setUp(self):
        super(GetJobDirectoriesTests, self).setUp()
        self.make_job_hierarchy()
        os.mkdir('not-a-job')
        open('not-a-dir', 'w').close()


    def _run_get_directories(self, cls, expected_list):
        """Test `get_job_directories()` for the given class.

        Calls the method, and asserts that the returned list of
        directories matches the expected return value.

        @param expected_list Expected return value from the call.
        """
        dirlist = cls.get_job_directories()
        self.assertEqual(set(dirlist), set(expected_list))


    def test_get_regular_jobs(self):
        """Test `RegularJobDirectory.get_job_directories()`."""
        self._run_get_directories(job_directories.RegularJobDirectory,
                                  self.REGULAR_JOBLIST)


    def test_get_special_jobs(self):
        """Test `SpecialJobDirectory.get_job_directories()`."""
        self._run_get_directories(job_directories.SpecialJobDirectory,
                                  self.SPECIAL_JOBLIST)


class AddJobsTests(_TempResultsDirTestBase):
    """Tests for `Offloader._add_new_jobs()`."""

    MOREJOBS = ['115-fubar', '116-fubar', '117-fubar', '118-snafu']

    def setUp(self):
        super(AddJobsTests, self).setUp()
        self._initial_job_names = (
            set(self.REGULAR_JOBLIST) | set(self.SPECIAL_JOBLIST))
        self.make_job_hierarchy()
        self._offloader = gs_offloader.Offloader(_get_options(['-a']))
        self.mox.StubOutWithMock(logging, 'debug')


    def _run_add_new_jobs(self, expected_key_set):
        """Basic test assertions for `_add_new_jobs()`.

        Asserts the following:
          * The keys in the offloader's `_open_jobs` dictionary
            matches the expected set of keys.
          * For every job in `_open_jobs`, the job has the expected
            directory name.

        """
        count = len(expected_key_set) - len(self._offloader._open_jobs)
        logging.debug(mox.IgnoreArg(), count)
        self.mox.ReplayAll()
        self._offloader._add_new_jobs()
        self.assertEqual(expected_key_set,
                         set(self._offloader._open_jobs.keys()))
        for jobkey, job in self._offloader._open_jobs.items():
            self.assertEqual(jobkey, job._dirname)
        self.mox.VerifyAll()
        self.mox.ResetAll()


    def test_add_jobs_empty(self):
        """Test adding jobs to an empty dictionary.

        Calls the offloader's `_add_new_jobs()`, then perform
        the assertions of `self._check_open_jobs()`.

        """
        self._run_add_new_jobs(self._initial_job_names)


    def test_add_jobs_non_empty(self):
        """Test adding jobs to a non-empty dictionary.

        Calls the offloader's `_add_new_jobs()` twice; once from
        initial conditions, and then again after adding more
        directories.  After the second call, perform the assertions
        of `self._check_open_jobs()`.  Additionally, assert that
        keys added by the first call still map to their original
        job object after the second call.

        """
        self._run_add_new_jobs(self._initial_job_names)
        jobs_copy = self._offloader._open_jobs.copy()
        for d in self.MOREJOBS:
            os.mkdir(d)
        self._run_add_new_jobs(self._initial_job_names |
                                 set(self.MOREJOBS))
        for key in jobs_copy.keys():
            self.assertIs(jobs_copy[key],
                          self._offloader._open_jobs[key])


class JobStateTests(_TempResultsDirTestBase):
    """Tests for job state predicates.

    This tests for the expected results from the
    `is_offloaded()` and `is_reportable()` predicate
    methods.

    """

    def test_unfinished_job(self):
        """Test that an unfinished job reports the correct state.

        A job is "unfinished" if it isn't marked complete in the
        database.  A job in this state is neither "complete" nor
        "reportable".

        """
        job = self.make_job(self.REGULAR_JOBLIST[0])
        self.assertFalse(job.is_offloaded())
        self.assertFalse(job.is_reportable())


    def test_incomplete_job(self):
        """Test that an incomplete job reports the correct state.

        A job is "incomplete" if exactly one attempt has been made
        to offload the job, but its results directory still exists.
        A job in this state is neither "complete" nor "reportable".

        """
        job = self.make_job(self.REGULAR_JOBLIST[0])
        job.set_incomplete()
        self.assertFalse(job.is_offloaded())
        self.assertFalse(job.is_reportable())


    def test_reportable_job(self):
        """Test that a reportable job reports the correct state.

        A job is "reportable" if more than one attempt has been made
        to offload the job, and its results directory still exists.
        A job in this state is "reportable", but not "complete".

        """
        job = self.make_job(self.REGULAR_JOBLIST[0])
        job.set_reportable()
        self.assertFalse(job.is_offloaded())
        self.assertTrue(job.is_reportable())


    def test_completed_job(self):
        """Test that a completed job reports the correct state.

        A job is "completed" if at least one attempt has been made
        to offload the job, and its results directory still exists.
        A job in this state is "complete", and not "reportable".

        """
        job = self.make_job(self.REGULAR_JOBLIST[0])
        job.set_complete()
        self.assertTrue(job.is_offloaded())
        self.assertFalse(job.is_reportable())


class ReportingTests(_TempResultsDirTestBase):
    """Tests for `Offloader._update_offload_results()`."""

    def setUp(self):
        super(ReportingTests, self).setUp()
        self._offloader = gs_offloader.Offloader(_get_options([]))
        self.mox.StubOutWithMock(email_manager.manager,
                                 'send_email')
        self.mox.StubOutWithMock(logging, 'debug')


    def _add_job(self, jobdir):
        """Add a job to the dictionary of unfinished jobs."""
        j = self.make_job(jobdir)
        self._offloader._open_jobs[j._dirname] = j
        return j


    def _expect_log_message(self, new_open_jobs, with_failures):
        """Mock expected logging calls.

        `_update_offload_results()` logs one message with the number
        of jobs removed from the open job set and the number of jobs
        still remaining.  Additionally, if there are reportable
        jobs, then it logs the number of jobs that haven't yet
        offloaded.

        This sets up the logging calls using `new_open_jobs` to
        figure the job counts.  If `with_failures` is true, then
        the log message is set up assuming that all jobs in
        `new_open_jobs` have offload failures.

        @param new_open_jobs New job set for calculating counts
                             in the messages.
        @param with_failures Whether the log message with a
                             failure count is expected.

        """
        count = len(self._offloader._open_jobs) - len(new_open_jobs)
        logging.debug(mox.IgnoreArg(), count, len(new_open_jobs))
        if with_failures:
            logging.debug(mox.IgnoreArg(), len(new_open_jobs))


    def _run_update_no_report(self, new_open_jobs):
        """Call `_update_offload_results()` expecting no report.

        Initial conditions are set up by the caller.  This calls
        `_update_offload_results()` once, and then checks these
        assertions:
          * The offloader's `_next_report_time` field is unchanged.
          * The offloader's new `_open_jobs` field contains only
            the entries in `new_open_jobs`.
          * The email_manager's `send_email` stub wasn't called.

        @param new_open_jobs A dictionary representing the expected
                             new value of the offloader's
                             `_open_jobs` field.
        """
        self.mox.ReplayAll()
        next_report_time = self._offloader._next_report_time
        self._offloader._update_offload_results()
        self.assertEqual(next_report_time,
                         self._offloader._next_report_time)
        self.assertEqual(self._offloader._open_jobs, new_open_jobs)
        self.mox.VerifyAll()
        self.mox.ResetAll()


    def _run_update_with_report(self, new_open_jobs):
        """Call `_update_offload_results()` expecting an e-mail report.

        Initial conditions are set up by the caller.  This calls
        `_update_offload_results()` once, and then checks these
        assertions:
          * The offloader's `_next_report_time` field is updated
            to an appropriate new time.
          * The offloader's new `_open_jobs` field contains only
            the entries in `new_open_jobs`.
          * The email_manager's `send_email` stub was called.

        @param new_open_jobs A dictionary representing the expected
                             new value of the offloader's
                             `_open_jobs` field.
        """
        logging.debug(mox.IgnoreArg())
        email_manager.manager.send_email(
            mox.IgnoreArg(), mox.IgnoreArg(), mox.IgnoreArg())
        self.mox.ReplayAll()
        t0 = time.time() + gs_offloader.REPORT_INTERVAL_SECS
        self._offloader._update_offload_results()
        t1 = time.time() + gs_offloader.REPORT_INTERVAL_SECS
        next_report_time = self._offloader._next_report_time
        self.assertGreaterEqual(next_report_time, t0)
        self.assertLessEqual(next_report_time, t1)
        self.assertEqual(self._offloader._open_jobs, new_open_jobs)
        self.mox.VerifyAll()
        self.mox.ResetAll()


    def test_no_jobs(self):
        """Test `_update_offload_results()` with no open jobs.

        Initial conditions are an empty `_open_jobs` list and
        `_next_report_time` in the past.  Expected result is no
        e-mail report, and an empty `_open_jobs` list.

        """
        self._expect_log_message({}, False)
        self._run_update_no_report({})


    def test_all_completed(self):
        """Test `_update_offload_results()` with only complete jobs.

        Initial conditions are an `_open_jobs` list consisting of
        only completed jobs and `_next_report_time` in the past.
        Expected result is no e-mail report, and an empty
        `_open_jobs` list.

        """
        for d in self.REGULAR_JOBLIST:
            self._add_job(d).set_complete()
        self._expect_log_message({}, False)
        self._run_update_no_report({})


    def test_none_finished(self):
        """Test `_update_offload_results()` with only unfinished jobs.

        Initial conditions are an `_open_jobs` list consisting of
        only unfinished jobs and `_next_report_time` in the past.
        Expected result is no e-mail report, and no change to the
        `_open_jobs` list.

        """
        for d in self.REGULAR_JOBLIST:
            self._add_job(d)
        new_jobs = self._offloader._open_jobs.copy()
        self._expect_log_message(new_jobs, False)
        self._run_update_no_report(new_jobs)


    def test_none_reportable(self):
        """Test `_update_offload_results()` with only incomplete jobs.

        Initial conditions are an `_open_jobs` list consisting of
        only incomplete jobs and `_next_report_time` in the past.
        Expected result is no e-mail report, and no change to the
        `_open_jobs` list.

        """
        for d in self.REGULAR_JOBLIST:
            self._add_job(d).set_incomplete()
        new_jobs = self._offloader._open_jobs.copy()
        self._expect_log_message(new_jobs, False)
        self._run_update_no_report(new_jobs)


    def test_report_not_ready(self):
        """Test `_update_offload_results()` e-mail throttling.

        Initial conditions are an `_open_jobs` list consisting of
        only reportable jobs but with `_next_report_time` in
        the future.  Expected result is no e-mail report, and no
        change to the `_open_jobs` list.

        """
        # N.B.  This test may fail if its run time exceeds more than
        # about _MARGIN_SECS seconds.
        for d in self.REGULAR_JOBLIST:
            self._add_job(d).set_reportable()
        self._offloader._next_report_time += _MARGIN_SECS
        new_jobs = self._offloader._open_jobs.copy()
        self._expect_log_message(new_jobs, True)
        self._run_update_no_report(new_jobs)


    def test_reportable(self):
        """Test `_update_offload_results()` with reportable jobs.

        Initial conditions are an `_open_jobs` list consisting of
        only reportable jobs and with `_next_report_time` in
        the past.  Expected result is an e-mail report, and no
        change to the `_open_jobs` list.

        """
        for d in self.REGULAR_JOBLIST:
            self._add_job(d).set_reportable()
        new_jobs = self._offloader._open_jobs.copy()
        self._expect_log_message(new_jobs, True)
        self._run_update_with_report(new_jobs)


    def test_reportable_mixed(self):
        """Test `_update_offload_results()` with a mixture of jobs.

        Initial conditions are an `_open_jobs` list consisting of
        one reportable jobs and the remainder of the jobs
        incomplete.  The value of `_next_report_time` is in the
        past.  Expected result is an e-mail report that includes
        both the reportable and the incomplete jobs, and no change
        to the `_open_jobs` list.

        """
        self._add_job(self.REGULAR_JOBLIST[0]).set_reportable()
        for d in self.REGULAR_JOBLIST[1:]:
            self._add_job(d).set_incomplete()
        new_jobs = self._offloader._open_jobs.copy()
        self._expect_log_message(new_jobs, True)
        self._run_update_with_report(new_jobs)


if __name__ == '__main__':
    unittest.main()