#!/usr/bin/env python
'''
Ohi = Openshift Host Inventory

This script provides an easy way to look at your host inventory.

This depends on multi_inventory being setup correctly.
'''
# vim: expandtab:tabstop=4:shiftwidth=4

import argparse
import sys
import os
import ConfigParser

from openshift_ansible import awsutil
from openshift_ansible import utils
from openshift_ansible.awsutil import ArgumentError

CONFIG_MAIN_SECTION = 'main'
CONFIG_HOST_TYPE_ALIAS_SECTION = 'host_type_aliases'


class Ohi(object):
    '''
        Class for managing openshift host inventory
    '''
    def __init__(self):
        self.host_type_aliases = {}
        self.file_path = os.path.join(os.path.dirname(os.path.realpath(__file__)))

        # Default the config path to /etc
        self.config_path = os.path.join(os.path.sep, 'etc',  \
                                        'openshift_ansible', \
                                        'openshift_ansible.conf')

        self.args = None
        self.parse_cli_args()
        self.parse_config_file()

        self.aws = awsutil.AwsUtil(self.host_type_aliases)

    def run(self):
        '''
            Call into awsutil and retrieve the desired hosts and environments
        '''

        if self.args.list_host_types:
            self.aws.print_host_types()
            return 0

        if self.args.v3:
            version = '3'
        elif self.args.all_versions:
            version = 'all'
        else:
            version = '2'

        hosts = self.aws.get_host_list(clusters=self.args.cluster,
                                       host_type=self.args.host_type,
                                       sub_host_type=self.args.sub_host_type,
                                       envs=self.args.env,
                                       version=version,
                                       cached=self.args.cache_only)

        if hosts is None:
            # We weren't able to determine what they wanted to do
            raise ArgumentError("Invalid combination of arguments")

        if self.args.ip:
            hosts = self.aws.convert_to_ip(hosts)

        for host in sorted(hosts, key=utils.normalize_dnsname):
            if self.args.user:
                print "%s@%s" % (self.args.user, host)
            else:
                print host

        return 0

    def parse_config_file(self):
        '''
            Parse the config file for ohi
        '''
        if os.path.isfile(self.config_path):
            config = ConfigParser.ConfigParser()
            config.read(self.config_path)

            self.host_type_aliases = {}
            if config.has_section(CONFIG_HOST_TYPE_ALIAS_SECTION):
                for alias in config.options(CONFIG_HOST_TYPE_ALIAS_SECTION):
                    value = config.get(CONFIG_HOST_TYPE_ALIAS_SECTION, alias).split(',')
                    self.host_type_aliases[alias] = value

    def parse_cli_args(self):
        """Setup the command line parser with the options we want
        """

        parser = argparse.ArgumentParser(description='OpenShift Host Inventory')

        parser.add_argument('--list-host-types', default=False, action='store_true', help='List all of the host types')
        parser.add_argument('--list', default=False, action='store_true', help='List all hosts')

        parser.add_argument('-c', '--cluster', action="append", help="Which clusterid to use")
        parser.add_argument('-e', '--env', action="append", help="Which environment to use")

        parser.add_argument('-t', '--host-type', action="store", help="Which host type to use")

        parser.add_argument('-s', '--sub-host-type', action="store", help="Which sub host type to use")

        parser.add_argument('-l', '--user', action='store', default=None, help='username')

        parser.add_argument('--cache-only', action='store_true', default=False,
                            help='Retrieve the host inventory by cache only. Default is false.')

        parser.add_argument('--v2', action='store_true', default=True,
                            help='Specify the openshift version. Default is 2')

        parser.add_argument('--v3', action='store_true', default=False,
                            help='Specify the openshift version.')

        parser.add_argument('--ip', action='store_true', default=False,
                            help='Return ip address only.')

        parser.add_argument('--all-versions', action='store_true', default=False,
                            help='Specify the openshift version. Return all versions')

        self.args = parser.parse_args()

def main():
    '''
    Ohi will do its work here
    '''
    if len(sys.argv) == 1:
        print "\nError: No options given. Use --help to see the available options\n"
        sys.exit(0)

    try:
        ohi = Ohi()
        exitcode = ohi.run()
        sys.exit(exitcode)
    except ArgumentError as err:
        print "\nError: %s\n" % err.message

if __name__ == '__main__':
    main()