import inspect
import logging
import os
import os.path
import shutil
from functools import partial
from unittest import mock

from pcs.common.file import RawFile
from pcs.common.node_communicator import NodeCommunicatorFactory
from pcs.lib.env import LibraryEnvironment

from pcs_test.tools import fixture
from pcs_test.tools.assertions import (
    assert_raise_library_error,
    prepare_diff,
)
from pcs_test.tools.case_analysis import test_failed
from pcs_test.tools.command_env import spy
from pcs_test.tools.command_env.calls import Queue as CallQueue
from pcs_test.tools.command_env.config import Config
from pcs_test.tools.command_env.mock_fs import (
    get_fs_mock,
    is_fs_call_in,
)
from pcs_test.tools.command_env.mock_get_local_corosync_conf import (
    get_get_local_corosync_conf,
)
from pcs_test.tools.command_env.mock_node_communicator import NodeCommunicator
from pcs_test.tools.command_env.mock_push_cib import (
    get_push_cib,
    is_push_cib_call_in,
)
from pcs_test.tools.command_env.mock_push_corosync_conf import (
    get_push_corosync_conf,
    is_push_corosync_conf_call_in,
)
from pcs_test.tools.command_env.mock_raw_file import get_raw_file_mock
from pcs_test.tools.command_env.mock_runner import Runner
from pcs_test.tools.command_env.mock_service_manager import ServiceManagerMock
from pcs_test.tools.custom_mock import MockLibraryReportProcessor

patch_lib_env = partial(mock.patch.object, LibraryEnvironment)


def patch_env(call_queue, config, init_env, is_systemd=True):
    # It is mandatory to patch some env objects/methods. It is ok when a
    # command does not use these objects/methods and specifies no calls for
    # them. But it would be a problem when a test succeeds thanks to a live
    # call responded correctly by accident. Such tests would fail on a
    # different machine (with an other live environment).

    orig_cmd_runner = init_env.cmd_runner
    get_node_communicator = init_env.get_node_communicator
    mock_communicator_factory = mock.Mock(spec_set=NodeCommunicatorFactory)
    mock_communicator_factory.get_communicator = (
        # TODO: use request_timeout
        lambda request_timeout=None: (
            NodeCommunicator(call_queue)
            if not config.spy
            else spy.NodeCommunicator(get_node_communicator())
        )
    )

    def get_cmd_runner(self, env=None):
        del self
        if config.spy:
            return spy.Runner(orig_cmd_runner())
        env_vars = {}
        if config.env.cib_tempfile:
            env_vars["CIB_file"] = config.env.cib_tempfile
        if env:
            env_vars.update(env)
        return Runner(call_queue, env_vars=env_vars)

    patcher_list = [
        patch_lib_env("cmd_runner", get_cmd_runner),
        mock.patch(
            "pcs.lib.env.get_local_corosync_conf",
            (
                get_get_local_corosync_conf(call_queue)
                if not config.spy
                else spy.get_local_corosync_conf
            ),
        ),
        patch_lib_env("communicator_factory", mock_communicator_factory),
        # Use our custom ServiceManager in tests
        # TODO: add support for Spy
        patch_lib_env(
            "_get_service_manager", lambda _: ServiceManagerMock(call_queue)
        ),
    ]
    if is_systemd:
        # In most test cases we don't care about underlying init system. But
        # some tests actually test different behavior based on init
        # system. This will cause pcs.lib.services.is_systemd(<instance of
        # ServiceManagerMock>) to return True because we replace SystemdDriver
        # in isinstance() call inside is_systemd function with
        # ServiceManagerMock. Otherwise is_systemd will return False.
        patcher_list.append(
            mock.patch(
                "pcs.lib.services.services.drivers.SystemdDriver",
                ServiceManagerMock,
            )
        )

    if is_fs_call_in(call_queue):
        fs_mock = get_fs_mock(call_queue)
        patcher_list.extend(
            [
                mock.patch("builtins.open", fs_mock("open", open)),
                mock.patch(
                    "os.path.exists", fs_mock("os.path.exists", os.path.exists)
                ),
                mock.patch(
                    "os.path.isdir", fs_mock("os.path.isdir", os.path.isdir)
                ),
                mock.patch(
                    "os.path.isfile", fs_mock("os.path.isfile", os.path.isfile)
                ),
                mock.patch("os.listdir", fs_mock("os.listdir", os.listdir)),
                mock.patch("os.chmod", fs_mock("os.chmod", os.chmod)),
                mock.patch("os.chown", fs_mock("os.chown", os.chown)),
                mock.patch(
                    "shutil.rmtree", fs_mock("shutil.rmtree", shutil.rmtree)
                ),
                mock.patch("os.makedirs", fs_mock("os.makedirs", os.makedirs)),
            ]
        )

    raw_file_mock = get_raw_file_mock(call_queue)
    for method_name, _ in inspect.getmembers(RawFile, inspect.isfunction):
        # patch all public methods
        # inspect.isfunction must be used instead of ismethod because we are
        # working with a class and not an instance - no method is bound yet so
        # it would return an empty list
        # "protected" methods start with _
        # "private" methods start with _<class_name>__
        if method_name.startswith("_"):
            continue
        patcher_list.append(
            mock.patch.object(
                RawFile, method_name, getattr(raw_file_mock, method_name)
            )
        )

    # It is not always desirable to patch these methods. Some tests may patch
    # only the internals (runner etc.). So these methods are only patched when
    # it is explicitly configured.
    if is_push_cib_call_in(call_queue):
        patcher_list.append(patch_lib_env("push_cib", get_push_cib(call_queue)))
    if is_push_corosync_conf_call_in(call_queue):
        patcher_list.append(
            patch_lib_env(
                "push_corosync_conf", get_push_corosync_conf(call_queue)
            )
        )

    for patcher in patcher_list:
        patcher.start()

    def unpatch():
        for patcher in patcher_list:
            patcher.stop()

    return unpatch


class EnvAssistant:
    # pylint: disable=too-many-instance-attributes
    def __init__(
        self,
        config=None,
        test_case=None,
        exception_reports_in_processor_by_default=True,
    ):
        """
        TestCase test_case -- cleanup callback is registered to test_case if is
            provided
        """
        self.__call_queue = None
        self.__config = config if config else Config()
        self.__reports_asserted = False
        self.__extra_reports = []
        self.exception_reports_in_processor_by_default = (
            exception_reports_in_processor_by_default
        )

        self.__unpatch = None
        self.__original_mocked_corosync_conf = None

        if test_case:
            test_case.addCleanup(lambda: self.cleanup(test_case))

    @property
    def config(self):
        return self.__config

    def cleanup(self, current_test):
        if self.__unpatch:
            self.__unpatch()

        if test_failed(current_test):
            # We have already got the message that main test failed. There is
            # a high probability that something remains in reports or in the
            # queue etc. But it is only consequence of the main test fail. And
            # we do not want to make the report confusing.
            return

        if not self.__reports_asserted:
            self.__assert_environment_created()
            if not self.__config.spy:
                self._env.report_processor.assert_reports(
                    self.__extra_reports,
                    hint="EnvAssistant.cleanup - is param"
                    " 'expected_in_processor' in the method"
                    " 'assert_raise_library_error' set correctly?",
                )

        if not self.__config.spy:
            if self.__call_queue and self.__call_queue.remaining:
                raise AssertionError(
                    "There are remaining expected calls: \n    '{0}'".format(
                        "'\n    '".join(
                            [repr(call) for call in self.__call_queue.remaining]
                        )
                    )
                )
            # If pushing corosync.conf has not been patched in the
            # LibraryEnvironment and the LibraryEnvironment was constructed
            # with a mocked corosync.conf, check if it was changed without the
            # change being specified in a test.
            # If no env.push_corosync_conf call has been specified, no mocking
            # occurs, any changes to corosync.conf are done just in memory and
            # nothing gets reported. So an explicit check is necessary.
            corosync_conf_orig = self.__original_mocked_corosync_conf
            # pylint: disable=protected-access
            corosync_conf_env = self._env._corosync_conf_data
            if corosync_conf_orig and corosync_conf_orig != corosync_conf_env:
                raise AssertionError(
                    (
                        "An unexpected change to corosync.conf in "
                        "LibraryEnvironment has been detected:\n{0}"
                    ).format(
                        prepare_diff(corosync_conf_orig, corosync_conf_env)
                    )
                )

    def get_env(self, is_systemd=True):
        self.__call_queue = CallQueue(self.__config.calls)
        # pylint: disable=attribute-defined-outside-init
        self._env = LibraryEnvironment(
            mock.MagicMock(logging.Logger),
            MockLibraryReportProcessor(),
            cib_data=self.__config.env.cib_data,
            corosync_conf_data=self.__config.env.corosync_conf_data,
            known_hosts_getter=(
                (lambda: self.__config.spy.known_hosts)
                if self.__config.spy
                else self.__config.env.known_hosts_getter
            ),
            booth_files_data=self.__config.env.booth,
        )
        self.__unpatch = patch_env(
            self.__call_queue,
            self.__config,
            self._env,
            is_systemd=is_systemd,
        )
        # If pushing corosync.conf has not been patched in the
        # LibraryEnvironment, store any corosync.conf passed to the
        # LibraryEnvironment for check for changes in cleanup.
        if not is_push_corosync_conf_call_in(self.__call_queue):
            self.__original_mocked_corosync_conf = (
                self.__config.env.corosync_conf_data
            )
        return self._env

    def assert_reports(self, expected_reports):
        self.__reports_asserted = True
        self.__assert_environment_created()
        if isinstance(expected_reports, fixture.ReportSequenceBuilder):
            expected_reports = expected_reports.fixtures.values
        elif isinstance(expected_reports, fixture.NameValueSequence):
            expected_reports = expected_reports.values
        self._env.report_processor.assert_reports(
            expected_reports + self.__extra_reports
        )

    def assert_raise_library_error(
        self, command, reports=None, expected_in_processor=None
    ):
        if reports is None:
            reports = []

        if not isinstance(reports, list):
            raise self.__list_of_reports_expected(reports)

        if expected_in_processor is None:
            expected_in_processor = (
                self.exception_reports_in_processor_by_default
            )

        assert_raise_library_error(command, *reports)
        if expected_in_processor:
            self.__extra_reports = reports

    def __assert_environment_created(self):
        if not hasattr(self, "_env"):
            raise AssertionError(
                "LibraryEnvironment was not created in EnvAssistant."
                " Have you called method get_env?"
            )

    def __list_of_reports_expected(self, reports):
        return AssertionError(
            (
                "{0}.{1} expects 'list' as reports parameter, '{2}' was given"
            ).format(
                self.__class__.__name__, "assert_raise", type(reports).__name__
            )
        )