#  Copyright (C) 2015-2018  Red Hat, Inc. <http://www.redhat.com>
#
#  This program is free software; you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation; either version 2 of the License, or
#  any later version.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License along
#  with this program; if not, write to the Free Software Foundation, Inc.,
#  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

from glusto.core import Glusto as g
from glustolibs.gluster.gluster_base_class import (GlusterBaseClass, runs_on)
from glustolibs.gluster.exceptions import ExecutionError
from glustolibs.gluster.heal_ops import trigger_heal
from glustolibs.gluster.volume_libs import get_subvols
from glustolibs.gluster.brick_libs import (bring_bricks_offline,
                                           bring_bricks_online,
                                           are_bricks_offline)
from glustolibs.gluster.heal_libs import (monitor_heal_completion,
                                          is_heal_complete,
                                          is_volume_in_split_brain)
from glustolibs.io.utils import (validate_io_procs,
                                 list_all_files_and_dirs_mounts,
                                 wait_for_io_to_complete)


@runs_on([['distributed-replicated'],
          ['glusterfs', 'nfs', 'cifs']])
class TestArbiterSelfHeal(GlusterBaseClass):
    """
    Description:
        Arbiter Test cases related to
        healing in default configuration of the volume
    """

    def setUp(self):
        # Calling GlusterBaseClass setUp
        GlusterBaseClass.setUp.im_func(self)

        # Setup Volumes
        if self.volume_type == "distributed-replicated":
            # Redefine distributed-replicated volume
            self.volume['voltype'] = {
                'type': 'distributed-replicated',
                'replica_count': 3,
                'dist_count': 2,
                'arbiter_count': 1,
                'transport': 'tcp'}

        self.all_mounts_procs = []
        self.io_validation_complete = False

        # Setup Volume and Mount Volume
        g.log.info("Starting to Setup Volume and Mount Volume")
        ret = self.setup_volume_and_mount_volume(mounts=self.mounts)
        if not ret:
            raise ExecutionError("Failed to Setup_Volume and Mount_Volume")
        g.log.info("Successful in Setup Volume and Mount Volume")

    def tearDown(self):
        """
        If test method failed before validating IO, tearDown waits for the
        IO's to complete and checks for the IO exit status

        Cleanup and umount volume
        """
        if not self.io_validation_complete:
            g.log.info("Wait for IO to complete as IO validation did not "
                       "succeed in test method")
            ret = wait_for_io_to_complete(self.all_mounts_procs, self.mounts)
            if not ret:
                raise ExecutionError("IO failed on some of the clients")
            g.log.info("IO is successful on all mounts")

            # List all files and dirs created
            g.log.info("List all files and directories:")
            ret = list_all_files_and_dirs_mounts(self.mounts)
            if not ret:
                raise ExecutionError("Failed to list all files and dirs")
            g.log.info("Listing all files and directories is successful")

        # Cleanup and umount volume
        g.log.info("Starting to Unmount Volume and Cleanup Volume")
        ret = self.unmount_volume_and_cleanup_volume(mounts=self.mounts)
        if not ret:
            raise ExecutionError("Failed to umount the vol & cleanup Volume")
        g.log.info("Successful in umounting the volume and Cleanup")

        # Calling GlusterBaseClass teardown
        GlusterBaseClass.tearDown.im_func(self)

    def test_resolving_meta_data(self):
        """
        - Create a file test_file.txt
        - Find out which brick the file resides on and kill arbiter brick
        in the replica pair
        - Modify the permissions of the file
        - Bring back the killed brick
        - Kill the other brick in the replica pair
        - Modify the permissions of the file
        - Bring back the killed brick
        - Trigger heal
        - Check if heal is completed
        - Check for split-brain
        """
        # pylint: disable=too-many-locals,too-many-statements
        # Creating files on client side
        file_to_create = 'test_file.txt'
        for mount_obj in self.mounts:
            g.log.info("Generating data for %s:%s",
                       mount_obj.client_system, mount_obj.mountpoint)
            # Create file
            g.log.info('Creating file...')
            command = ("cd %s ; "
                       "touch %s"
                       % (mount_obj.mountpoint, file_to_create))

            proc = g.run_async(mount_obj.client_system, command,
                               user=mount_obj.user)
            self.all_mounts_procs.append(proc)
        self.io_validation_complete = False

        # Validate IO
        self.assertTrue(
            validate_io_procs(self.all_mounts_procs, self.mounts),
            "IO failed on some of the clients"
        )
        self.io_validation_complete = True

        # get bricks with file
        g.log.info('Getting bricks with file...')
        subvols_dict = get_subvols(self.mnode, self.volname)
        brick_list_with_file = []
        for subvol in subvols_dict['volume_subvols']:
            for brick in subvol:
                node, brick_path = brick.split(':')
                ret, brick_file_list, _ = g.run(node, 'ls %s' % brick_path)
                if 'test_file.txt' in brick_file_list:
                    brick_list_with_file.append(brick)
        g.log.info('Bricks with file: %s', brick_list_with_file)

        # Bring arbiter brick offline
        bricks_to_bring_offline = [brick_list_with_file[-1]]
        g.log.info('Bringing bricks %s offline...', bricks_to_bring_offline)
        ret = bring_bricks_offline(self.volname, bricks_to_bring_offline)
        self.assertTrue(ret, 'Failed to bring bricks %s offline' %
                        bricks_to_bring_offline)

        ret = are_bricks_offline(self.mnode, self.volname,
                                 bricks_to_bring_offline)
        self.assertTrue(ret, 'Bricks %s are not offline'
                        % bricks_to_bring_offline)
        g.log.info('Bringing bricks %s offline is successful',
                   bricks_to_bring_offline)

        # Modify the data
        self.all_mounts_procs = []
        for mount_obj in self.mounts:
            g.log.info("Modifying data for %s:%s",
                       mount_obj.client_system, mount_obj.mountpoint)
            # Modify the permissions
            g.log.info('Modifying the permissions of the file...')
            command = ("cd %s ; "
                       "chmod 600 %s"
                       % (mount_obj.mountpoint, file_to_create))

            proc = g.run_async(mount_obj.client_system, command,
                               user=mount_obj.user)
            self.all_mounts_procs.append(proc)
        self.io_validation_complete = False

        # Validate IO
        self.assertTrue(
            validate_io_procs(self.all_mounts_procs, self.mounts),
            "IO failed on some of the clients"
        )
        self.io_validation_complete = True

        # Bring arbiter brick online
        g.log.info('Bringing bricks %s online...', bricks_to_bring_offline)
        ret = bring_bricks_online(self.mnode, self.volname,
                                  bricks_to_bring_offline)
        self.assertTrue(ret, 'Failed to bring bricks %s online' %
                        bricks_to_bring_offline)
        g.log.info('Bringing bricks %s online is successful',
                   bricks_to_bring_offline)

        # Bring 1-st data brick offline
        bricks_to_bring_offline = [brick_list_with_file[0]]
        g.log.info('Bringing bricks %s offline...', bricks_to_bring_offline)
        ret = bring_bricks_offline(self.volname, bricks_to_bring_offline)
        self.assertTrue(ret, 'Failed to bring bricks %s offline' %
                        bricks_to_bring_offline)

        ret = are_bricks_offline(self.mnode, self.volname,
                                 bricks_to_bring_offline)
        self.assertTrue(ret, 'Bricks %s are not offline'
                        % bricks_to_bring_offline)
        g.log.info('Bringing bricks %s offline is successful',
                   bricks_to_bring_offline)

        # Modify the data
        self.all_mounts_procs = []
        for mount_obj in self.mounts:
            g.log.info("Modifying data for %s:%s",
                       mount_obj.client_system, mount_obj.mountpoint)
            # Modify the permissions
            g.log.info('Modifying the permissions of the file...')
            command = ("cd %s ; "
                       "chmod 644 %s"
                       % (mount_obj.mountpoint, file_to_create))

            proc = g.run_async(mount_obj.client_system, command,
                               user=mount_obj.user)
            self.all_mounts_procs.append(proc)
        self.io_validation_complete = False

        # Validate IO
        self.assertTrue(
            validate_io_procs(self.all_mounts_procs, self.mounts),
            "IO failed on some of the clients"
        )
        self.io_validation_complete = True

        # Bring 1-st data brick online
        g.log.info('Bringing bricks %s online...', bricks_to_bring_offline)
        ret = bring_bricks_online(self.mnode, self.volname,
                                  bricks_to_bring_offline)
        self.assertTrue(ret, 'Failed to bring bricks %s online' %
                        bricks_to_bring_offline)
        g.log.info('Bringing bricks %s online is successful',
                   bricks_to_bring_offline)

        # Start healing
        ret = trigger_heal(self.mnode, self.volname)
        self.assertTrue(ret, 'Heal is not started')
        g.log.info('Healing is started')

        # Monitor heal completion
        ret = monitor_heal_completion(self.mnode, self.volname)
        self.assertTrue(ret, 'Heal has not yet completed')

        # Check if heal is completed
        ret = is_heal_complete(self.mnode, self.volname)
        self.assertTrue(ret, 'Heal is not complete')
        g.log.info('Heal is completed successfully')

        # Check for split-brain
        ret = is_volume_in_split_brain(self.mnode, self.volname)
        self.assertFalse(ret, 'Volume is in split-brain state')
        g.log.info('Volume is not in split-brain state')