#!/usr/bin/env python
# -*- coding: utf-8 -*-
#
# MIDTOOLS.PY -- Gestion de la conversion mid <-> IP
#
# Copyright (C) 2010 Olivier Iffrig
# Authors: Olivier Iffrig <iffrig@crans.org>
#
# 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 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

from config import mid, prefix, NETs

import iptools

class Mid(object):
    """
    Permet de décortiquer un mid et d'obtenir les IP correspondantes
    """

    def __init__(self, mid):
        self.mid = mid
        self.type = None
        for tp in mid:
            if mid <= tp[1] and mid >= tp[0]:
                self.type = tp
        if self.type is None:
            raise ValueError("mid inconnu : %d" % mid)

        self.ipv4_dispo = False
        if (mid & (1 << 15)) == 0 and self.type != 'special':
            self.ipv4_dispo = True

        self.priv = True
        if (mid & (1 << 14)) == 0:
            self.priv = False

        self.reste = mid & 0x7ff
#        if self.type == 'ens': # Inutile pour l'instant
#            self.reste &= 0xff

    def to_ipv4(self):
        """
        Génère l'IPv4 associée à la machine
        """
        if not self.ipv4_dispo:
            raise ValueError("Pas d'adresse ipv4 disponible pour la machine")

        ip = iptools.param(NETs[self.type], True)['network']
        ip += self.reste
        return iptools.DecToQuad(ip)

    def to_ipv6_vlan(self):
        """
        Génère le VLAN IPv6 associé à la machine
        """
        if priv:
            raise ValueError("Pas d'adresse ipv6 disponible pour la machine")

        tp = {'fil': 'fil', 'fil-v6': 'fil',
              'wifi': 'wifi', 'wifi-v6': 'wifi',
              'adm': 'adm'}[self.type]
        ip = prefix[tp][0].split(":/")[0]
        ip += hex(self.mid)[2:]
        ip += "::/64"