#!/usr/bin/env python

import argparse
import errno
import os
import socket
import subprocess
import sys

path = os.path.dirname(os.path.realpath(__file__))
path = os.path.realpath(os.path.join(path, '..', 'lib', 'python'))
if path.startswith('/opt'):
    # if installed into system path, do not muck with things
    sys.path.append(path)

import confluent.client as client
import confluent.tlvdata as tlvdata

try:
    input = raw_input
except NameError:
    pass

def make_certificate():
    umask = os.umask(0077)
    try:
        os.makedirs('/etc/confluent/cfg')
    except OSError as e:
        if e.errno == errno.EEXIST and os.path.isdir('/etc/confluent/cfg'):
            pass
        else:
            raise
    if subprocess.check_call(
            'openssl ecparam -name secp384r1 -genkey -out '
            '/etc/confluent/privkey.pem'.split(' ')):
        raise Exception('Error generating private key')

    if subprocess.check_call('openssl req -new -x509 -key '
                              '/etc/confluent/privkey.pem -days 7300 -out '
                              '/etc/confluent/srvcert.pem -subj /CN='
                              '{0}'.format(socket.gethostname()).split(' ')):
        raise Exception('Error generating certificate')
    print('Certificate generated successfully')
    os.umask(umask)


def show_invitation(name):
    if not os.path.exists('/etc/confluent/srvcert.pem'):
        make_certificate()
    s = client.Command().connection
    tlvdata.send(s, {'collective': {'operation': 'invite', 'name': name}})
    invite = tlvdata.recv(s)['collective']
    if 'error' in invite:
        sys.stderr.write(invite['error'] + '\n')
        return
    print('{0}'.format(invite['invitation']))


def join_collective(server, invitation):
    if not os.path.exists('/etc/confluent/srvcert.pem'):
        make_certificate()
    s = client.Command().connection
    while not invitation:
        invitation = raw_input('Paste the invitation here: ')
    tlvdata.send(s, {'collective': {'operation': 'join',
                                    'invitation': invitation,
                                    'server': server}})
    res = tlvdata.recv(s)
    print(res.get('collective',
                  {'status': 'Unknown response: ' + repr(res)})['status'])


def show_collective():
    s = client.Command().connection
    tlvdata.send(s, {'collective': {'operation': 'show'}})
    res = tlvdata.recv(s)
    print(repr(res))

def main():
    a = argparse.ArgumentParser(description='Confluent server utility')
    sp = a.add_subparsers(dest='command')
    gc = sp.add_parser('gencert', help='Generate Confluent Certificates for '
                                'collective mode and remote CLI access')
    sl = sp.add_parser('show', help='Show information about the collective')
    ic = sp.add_parser('invite', help='Generate a invitation to allow a new '
                                    'confluent instance to join as a '
                                    'collective member')
    ic.add_argument('name', help='Name of server to invite to join the '
                                 'collective')
    jc = sp.add_parser('join', help='Join a collective')
    jc.add_argument('server', help='A server currently in the collective')
    jc.add_argument('-i', help='Invitation provided by runniing invite on an '
                               'existing collective member')
    cmdset = a.parse_args()
    if cmdset.command == 'gencert':
        make_certificate()
    elif cmdset.command == 'invite':
        show_invitation(cmdset.name)
    elif cmdset.command == 'join':
        join_collective(cmdset.server, cmdset.i)
    elif cmdset.command == 'show':
        show_collective()

if __name__ == '__main__':
    main()