#!/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 os
import re
import argparse
import ConfigParser

import config
from node import Node

parser = argparse.ArgumentParser (
    prog='mclu',
    description='Mini virtualization cluster management tool',
)
parser.add_argument (
    '-f',
    type=file,
    help='specify location of the configuration file',
    metavar='MCLU.CONF',
)

# Add subcommands.
subparsers = parser.add_subparsers ()
import mclu_build
mclu_build.cmdline (subparsers)
import mclu_console
mclu_console.cmdline (subparsers)
import mclu_info
mclu_info.cmdline (subparsers)
import mclu_list
mclu_list.cmdline (subparsers)
import mclu_migrate
mclu_migrate.cmdline (subparsers)
import mclu_shutdown
mclu_shutdown.cmdline (subparsers)
import mclu_start
mclu_start.cmdline (subparsers)
import mclu_status
mclu_status.cmdline (subparsers)
import mclu_stop
mclu_stop.cmdline (subparsers)
import mclu_viewer
mclu_viewer.cmdline (subparsers)
import mclu_wake
mclu_wake.cmdline (subparsers)

args = parser.parse_args()

# Default location of the config file if not defined on the command line:
if not args.f:
    config_dir = config.sysconfdir + "/" + config.PACKAGE_NAME
    args.f = open (config_dir + "/" + "mclu.conf")
else:
    # config_dir is the directory containing mclu.conf
    config_dir = os.path.dirname (args.f.name)

# Configuration file default settings.  You cannot set defaults per
# section, so we have to rely on setting names not overlapping.
conf_defaults = {
    "home" : os.getenv ("HOME"),
    "host" : "SET.THIS.IN.MCLU.CONF",
    "config_dir" : config_dir,
    "uri" : "qemu+ssh://root@%(host)s/system",
}

# Read the configuration file.
conf = ConfigParser.SafeConfigParser (conf_defaults)
conf.readfp (args.f)

# Global configuration.
images_dir = conf.get ("global", "images_dir")
if not os.path.isdir (images_dir):
    sys.exit ("configuration error: [globals] 'images_dir' (%s) directory does not exist" % images_dir)
xmls_dir = conf.get ("global", "xmls_dir")
if not os.path.isdir (xmls_dir):
    sys.exit ("configuration error: [globals] 'xmls_dir' (%s) directory does not exist", xmls_dir)

# Get the list of node names.
node_names = conf.items ("nodes")
node_names = filter (lambda (x, _) : re.search (r'^node', x), node_names)
node_names = [ value for _, value in node_names ]
if not node_names:
    sys.exit ("configuration error: [nodes] section in configuration file is empty")

# Get information about each node.
nodes = {}
for node_name in node_names:
    host = conf.get (node_name, "host")
    if not host:
        host = node
    mac = conf.get (node_name, "mac")
    uri = conf.get (node_name, "uri")
    node = Node (node_name, host, mac, uri)
    nodes[node_name] = node

# A config dict with less-used configuration settings.
c = {
    "config_file" : args.f.name,
    "config_dir" : config_dir,
    "images_dir" : images_dir,
    "node_names" : node_names,
    "xmls_dir" : xmls_dir,

    "conf" : conf,
}

# Run the subcommand.
args.run (c, args, nodes)