# -*- coding: utf-8 -*-

""" License

    Copyright (C) 2013 YunoHost

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as published
    by the Free Software Foundation, either version 3 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 Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program; if not, see http://www.gnu.org/licenses

"""

""" yunohost_dyndns.py

    Subscribe and Update DynDNS Hosts
"""
import logging
logging.warning('the module yunohost.dyndns has not been revisited and updated yet')

import os
import sys
import requests
import json
import glob
import base64

from moulinette.helpers import YunoHostError, YunoHostLDAP, validate, colorize, win_msg

def dyndns_subscribe(subscribe_host="dyndns.yunohost.org", domain=None, key=None):
    """
    Subscribe to a DynDNS service

    Keyword argument:
        domain -- Full domain to subscribe with
        key -- Public DNS key
        subscribe_host -- Dynette HTTP API to subscribe to

    """
    if domain is None:
        with open('/etc/yunohost/current_host', 'r') as f:
            domain = f.readline().rstrip()

    # Verify if domain is available
    if requests.get('http://'+ subscribe_host +'/test/'+ domain).status_code != 200:
        raise YunoHostError(17, _("DynDNS domain is already taken"))

    if key is None:
        if len(glob.glob('/etc/yunohost/dyndns/*.key')) == 0:
            os.makedirs('/etc/yunohost/dyndns')
            print(_("DNS key is being generated, it may take a while..."))
            os.system('cd /etc/yunohost/dyndns && dnssec-keygen -a hmac-md5 -b 128 -n USER '+ domain)
            os.system('chmod 600 /etc/yunohost/dyndns/*.key /etc/yunohost/dyndns/*.private')

        key_file = glob.glob('/etc/yunohost/dyndns/*.key')[0]
        with open(key_file) as f:
            key = f.readline().strip().split(' ')[-1]

    # Send subscription
    r = requests.post('http://'+ subscribe_host +'/key/'+ base64.b64encode(key), data={ 'subdomain': domain })
    if r.status_code != 201:
        try:    error = json.loads(r.text)['error']
        except: error = "Server error"
        raise YunoHostError(1, _("An error occured during DynDNS registration: "+ error))

    win_msg(_("Subscribed to DynDNS"))

    dyndns_installcron()


def dyndns_update(dyn_host="dynhost.yunohost.org", domain=None, key=None, ip=None):
    """
    Update IP on DynDNS platform

    Keyword argument:
        domain -- Full domain to subscribe with
        dyn_host -- Dynette DNS server to inform
        key -- Public DNS key
        ip -- IP address to send

    """
    if domain is None:
        with open('/etc/yunohost/current_host', 'r') as f:
            domain = f.readline().rstrip()

    if ip is None:
        new_ip = requests.get('http://ip.yunohost.org').text
    else:
        new_ip = ip

    try:
        with open('/etc/yunohost/dyndns/old_ip', 'r') as f:
            old_ip = f.readline().rstrip()
    except IOError:
        old_ip = '0.0.0.0'

    if old_ip != new_ip:
        host = domain.split('.')[1:]
        host = '.'.join(host)
        lines = [
            'server '+ dyn_host,
            'zone '+ host,
            'update delete '+ domain +'. A',
            'update delete '+ domain +'. MX',
            'update delete '+ domain +'. TXT',
            'update delete pubsub.'+ domain +'. A',
            'update delete muc.'+ domain +'. A',
            'update delete vjud.'+ domain +'. A',
            'update delete _xmpp-client._tcp.'+ domain +'. SRV',
            'update delete _xmpp-server._tcp.'+ domain +'. SRV',
            'update add '+ domain +'. 1800 A '+ new_ip,
            'update add '+ domain +'. 14400 MX 5 '+ domain +'.',
            'update add '+ domain +'. 14400 TXT "v=spf1 a mx -all"',
            'update add pubsub.'+ domain +'. 1800 A '+ new_ip,
            'update add muc.'+ domain +'. 1800 A '+ new_ip,
            'update add vjud.'+ domain +'. 1800 A '+ new_ip,
            'update add _xmpp-client._tcp.'+ domain +'. 14400 SRV 0 5 5222 '+ domain +'.',
            'update add _xmpp-server._tcp.'+ domain +'. 14400 SRV 0 5 5269 '+ domain +'.',
            'show',
            'send'
        ]
        with open('/etc/yunohost/dyndns/zone', 'w') as zone:
            for line in lines:
                zone.write(line + '\n')

        if key is None:
            private_key_file = glob.glob('/etc/yunohost/dyndns/*.private')[0]
        else:
            private_key_file = key
        if os.system('/usr/bin/nsupdate -k '+ private_key_file +' /etc/yunohost/dyndns/zone') == 0:
            win_msg(_("IP successfully updated"))
            with open('/etc/yunohost/dyndns/old_ip', 'w') as f:
                f.write(new_ip)
        else:
            os.remove('/etc/yunohost/dyndns/old_ip')
            raise YunoHostError(1, _("An error occured during DynDNS update"))


def dyndns_installcron():
    """
    Install IP update cron


    """
    os.system("touch /etc/cron.d/yunohost-dyndns")
    os.system("echo '*/2 * * * * root yunohost dyndns update --no-ldap >> /dev/null' >/etc/cron.d/yunohost-dyndns")
    win_msg(_("DynDNS cron installed"))


def dyndns_removecron():
    """
    Remove IP update cron


    """
    try:
        os.remove("/etc/cron.d/yunohost-dyndns")
    except:
        raise YunoHostError(167,_("DynDNS cron was not installed!"))

    win_msg(_("DynDNS cron removed"))