#!/usr/bin/python
# mclu (mini cluster)
# Copyright (C) 2014 Red Hat Inc.
#
# 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

import argparse
import os
import re
import sys
import subprocess

import config
import lib
import libvirt_xml

def cmdline (subparsers):
    p = subparsers.add_parser (
        'import',
        help='import and existing virtual machine',
    )
    p.add_argument (
        '--memory', default=1024, type=int,
        help='RAM to give to guest (default unit is megabytes)'
    )
    p.add_argument (
        '--vcpus', default=4, type=int,
        help='virtual CPUs to give to guest'
    )
    p.add_argument (
        '--virtio', default=True,
        help='use virtio disks and network'
    )
    p.add_argument (
        'name',
        help='name of the new VM (or use "vm:name")'
    )
    p.add_argument (
        'disk',
        help='disk image to import'
    )
    p.set_defaults (run=run)

def run (c, args):
    # Did the user request a particular node?  If not, we'll run it
    # on any node which is up.
    m = re.match (r'^(.*):(.*)$', args.name)
    if m:
        node_name = m.group (1)
        vm_name = m.group (2)
    else:
        node_name = lib.pick_any_node_which_is_up (c)
        vm_name = args.name

    # Get all the guests, so we can tell if the name is a duplicate.
    running, inactive = lib.get_all_guests (c)

    if vm_name in running or vm_name in inactive:
        sys.exit ("error: VM name (%s) already exists" % vm_name)

    output = '%s/%s.img' % (c['images_dir'], vm_name)

    # Use qemu-img to convert the input format (whatever it is) to qcow2,
    # and also to copy it.
    subprocess.check_call ([
        "qemu-img",
        "convert",
        args.disk,
        "-O", "qcow2",
        output
    ])

    # XXX Unfortunately this is necessary so qemu can access the disk.
    os.chmod (output, 0666)

    # Generate the XML.  Would be nice to use virt-install here, but
    # it doesn't work: RHBZ#1095789
    xml = libvirt_xml.generate_libvirt_xml (vm_name,
                                            args.memory,
                                            args.vcpus,
                                            args.virtio,
                                            output)

    # Write the XML to the xmls_dir.
    fp = open ("%s/%s.xml" % (c['xmls_dir'], vm_name), "w")
    fp.write (xml)
    fp.close ()

    # Start the guest.
    lib.start_guest (c, node_name, vm_name)
    print "guest imported and started on node %s" % node_name