# Copyright (c) 2018-2019 Hewlett Packard Enterprise Development LP
#
# 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 logging
import os

import fixtures
import testtools


class ChannelFixture(fixtures.Fixture):

    def __init__(self, channel='stdout', object=None):

        self._channel = channel
        if object is None:
            self._object = 'sys.%s' % channel
        else:
            self._object = object

    def _setUp(self):
        string_fixture = self.useFixture(fixtures.StringStream(self._channel))
        self.stream = string_fixture.stream
        self.useFixture(
            fixtures.MonkeyPatch(self._object, self.stream)
        )

    def getvalue(self):
        self.stream.seek(0)
        return self.stream.read()


class BaseTestCase(testtools.TestCase):

    def setUp(self):
        super(BaseTestCase, self).setUp()

        # capture stdout/stderr for tests to inspect easily
        self.stdout = self.useFixture(ChannelFixture('stdout'))
        self.stderr = self.useFixture(ChannelFixture('stderr'))
        self.logger = self.useFixture(
            fixtures.FakeLogger(
                level=logging.DEBUG,
                format="%(levelname)s:%(name)s:%(message)s"
            )
        )

    def get_testfile(self, ext):

        *path_parts, clsname, testname = self.id().split('.')
        testname = testname.replace("test_", '', 1)
        possible_test_fixtures = (
            "%s.%s.%s.%s" % (path_parts[-1], clsname, testname, ext),
            "%s.%s.%s" % (path_parts[-1], clsname, ext),
            "%s.%s" % (path_parts[-1], ext),
        )
        for fpath in possible_test_fixtures:
            testdatafile = os.path.join(*(path_parts[:-1]), "fixtures", fpath)
            if os.path.exists(testdatafile):
                return testdatafile
        else:
            self.test_logger.warn(
                "No file with test data found from patterns (%s) for test "
                "id %s" % (", ".join(possible_test_fixtures), self.id())
            )


class IsOrderedSubsetOfMismatch(object):
    def __init__(self, subset, set):
        self.subset = list(subset)
        self.set = list(set)

    def describe(self):
        return "set %r is not an ordered subset of %r" % (
            self.subset, self.set)

    def get_details(self):
        return {}


class IsOrderedSubsetOf(object):
    """Matches if the actual matches the order of iterable."""

    def __init__(self, iterable):
        self.iterable = iterable

    def __str__(self):
        return 'IsOrderedSubsetOf(%s)' % self.iterable

    def match(self, actual):
        iterable = iter(self.iterable)
        if all(item in iterable for item in actual):
            return None
        else:
            return IsOrderedSubsetOfMismatch(actual, self.iterable)