# Project Kimchi
#
# Copyright IBM Corp, 2015-2016
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library 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
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
import platform
import threading

import libvirt
import psutil
from wok.plugins.kimchi.config import get_libvirt_path
from wok.rollbackcontext import RollbackContext

KVMUSERTEST_VM_NAME = 'KVMUSERTEST_VM'


class UserTests(object):
    SIMPLE_VM_XML = """
    <domain type='kvm'>
      <name>%(name)s</name>
      <memory unit='KiB'>262144</memory>
      <os>
        <type arch='%(arch)s'>hvm</type>
        <boot dev='hd'/>
      </os>
      <on_poweroff>destroy</on_poweroff>
      <on_reboot>restart</on_reboot>
      <on_crash>restart</on_crash>
      <cpu mode='host-passthrough'>
      </cpu>
    </domain>"""
    lock = threading.Lock()
    user = None

    @classmethod
    def probe_user(cls):
        with cls.lock:
            if cls.user:
                return cls.user

        arch = 'ppc64' if platform.machine() == 'ppc64le' else platform.machine()

        xml = cls.SIMPLE_VM_XML % {'name': KVMUSERTEST_VM_NAME, 'arch': arch}

        with RollbackContext() as rollback:
            with cls.lock:
                conn = libvirt.open(None)
                rollback.prependDefer(conn.close)
                f = libvirt.VIR_DOMAIN_START_AUTODESTROY
                dom = conn.createXML(xml, flags=f)
                rollback.prependDefer(dom.destroy)
                filename = get_libvirt_path() + '/qemu/%s.pid' % KVMUSERTEST_VM_NAME
                with open(filename) as f:
                    pidStr = f.read()
                p = psutil.Process(int(pidStr))

                # bug fix #357
                # in psutil 2.0 and above versions, username will be a method,
                # not a string
                if callable(p.username):
                    cls.user = p.username()
                else:
                    cls.user = p.username

        return cls.user


if __name__ == '__main__':
    ut = UserTests()
    print(ut.probe_user())