#!/usr/bin/env python
#  -*- coding: utf-8 -*-
### BEGIN INIT INFO
# Provides: secop-server
# Required-Start: $local_fs $remote_fs $network $named $time
# Required-Stop: $local_fs $remote_fs $network
# Should-Start: 
# Default-Start: 2 3 4 5
# Default-Stop: 0 1 6
# Description: Secop servers
### END INIT INFO
# *****************************************************************************
#
# 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 (at your option) 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.,
# 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
#
# Module authors:
#   Alexander Lenz <alexander.lenz@frm2.tum.de>
#
# *****************************************************************************

import sys
import argparse
import os.path
import glob
import signal


CFG_DIR = '/etc/secop'
PID_DIR = '/var/run'
SRV_EXEC = 'secop-server'

inplace_basedir = os.path.join(os.path.dirname(__file__), '..')
if os.path.isfile(os.path.join(inplace_basedir, 'src', '__init__.py')):
    CFG_DIR = os.path.join(inplace_basedir, 'etc')
    PID_DIR = os.path.join(inplace_basedir, 'pid')
    SRV_EXEC = os.path.join(inplace_basedir, 'bin/secop-server')


def parseArgv(argv):
    parser = argparse.ArgumentParser(description='Manage a SECoP server')
    parser.add_argument('action',
                        type=str,
                        choices=['start', 'stop', 'restart', 'status'],
                        help='What to do with the desired server', )
    parser.add_argument('name',
                        nargs='*',
                        help='Name of the instance.\n'
                        ' Uses etc/name.cfg for configuration\n',)
    return parser.parse_args()


def getServerNames():
    return sorted([os.path.basename(entry)[:-4]
                   for entry in glob.glob(os.path.join(CFG_DIR, '*.cfg'))])


def getSrvPid(name):
    pidfile = os.path.join(PID_DIR, '%s.pid' % name)
    if not os.path.isfile(pidfile):
        return None
    with open(pidfile) as f:
        return int(f.read())


def startServer(name):
    pid = getSrvPid(name)

    if pid:
        print('%s: already running (pid: %s)' % (name, pid))
    else:
        print('%s: starting ...' % name)
        os.system('%s -d %s' % (SRV_EXEC, name))


def stopServer(name):
    pid = getSrvPid(name)
    if pid:
        print('%s: stopping ...' % name)
        os.kill(pid, signal.SIGTERM)
    else:
        print('%s: already stopped' % name)


def determineServerStatus(name):
    pid = getSrvPid(name)

    if pid:
        print('%s: running (pid: %s)' % (name, pid))
    else:
        print('%s: dead' % name)


def main(argv=None):
    if argv is None:
        argv = sys.argv

    args = parseArgv(argv[1:])

    actionMap = {
        'start': startServer,
        'stop': stopServer,
        'status': determineServerStatus,
    }

    srvs = args.name
    if not srvs:
        srvs = getServerNames()

    for entry in srvs:
        actionMap[args.action](entry)


if __name__ == '__main__':
    sys.exit(main(sys.argv))