#!/usr/bin/env python
#  Copyright (C) 2015-2016  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.

"""
    Description: This file contains the methods for starting/stopping glusterd
        and other initial gluster environment setup helpers.
"""
from glusto.core import Glusto as g


def start_glusterd(servers):
    """Starts glusterd on specified servers if they are not running.

    Args:
        servers (list): List of server hosts  on which glusterd has to be
            started.

    Returns:
        bool : True if starting glusterd is successful on all servers.
            False otherwise.
    """
    cmd = "pgrep glusterd || service glusterd start"
    results = g.run_parallel(servers, cmd)

    rc = True
    for server, ret_values in results.iteritems():
        retcode, out, err = ret_values
        if retcode != 0:
            g.log.error("Unable to start glusterd on server %s", server)
            rc = False
    if not rc:
        return False

    return True


def stop_glusterd(servers):
    """Stops the glusterd on specified servers.

    Args:
        servers (list): List of server hosts on which glusterd has to be
            stopped.

    Returns:
        bool : True if stopping glusterd is successful on all servers.
            False otherwise.
    """
    cmd = "service glusterd stop"
    results = g.run_parallel(servers, cmd)

    rc = True
    for server, ret_values in results.iteritems():
        retcode, out, err = ret_values
        if retcode != 0:
            g.log.error("Unable to start glusterd on server %s", server)
            rc = False
    if not rc:
        return False

    return True


def restart_glusterd(servers):
    """Restart the glusterd on specified servers.

    Args:
        servers (list): List of server hosts on which glusterd has to be
            restarted.

    Returns:
        bool : True if restarting glusterd is successful on all servers.
            False otherwise.
    """
    cmd = "service glusterd restart"
    results = g.run_parallel(servers, cmd)

    rc = True
    for server, ret_values in results.iteritems():
        retcode, out, err = ret_values
        if retcode != 0:
            g.log.error("Unable to restart glusterd on server %s", server)
            rc = False
    if not rc:
        return False

    return True


def is_glusterd_running(servers):
    """Checks the glusterd status on specified servers.

    Args:
        servers (list): List of server hosts on which glusterd status has to
        be checked.

    Returns:
            0  : if glusterd running
            1  : if glusterd not running
           -1  : if glusterd not running and PID is alive

    """
    cmd1 = "service glusterd status"
    cmd2 = "pidof glusterd"
    cmd1_results = g.run_parallel(servers, cmd1)
    cmd2_results = g.run_parallel(servers, cmd2)

    rc = 0
    for server, ret_values in cmd1_results.iteritems():
        retcode, out, err = ret_values
        if retcode != 0:
            g.log.error("glusterd is not running on the server %s", server)
            rc = 1
            if cmd2_results[server][0] == 0:
                g.log.error("PID of glusterd is alive and status is not "
                            "running")
                rc = -1
    return rc


# TODO: THIS IS NOT IMPLEMENTED YET. PLEASE DO THIS MANUALLY
# TILL WE IMPLEMENT THIS
def env_setup_servers(servers):
    """Set up environment on all the specified servers.

    Args:
        servers (list): List of server hosts  on which environment has to be
            setup.

    Returns:
        bool : True if setting up environment is successful on all servers.
            False otherwise.

    """
    g.log.info("The function isn't implemented fully")
    g.log.info("Please setup the bricks manually.")

    if not start_glusterd(servers):
        return False

    return True