#!/usr/bin/env python

# -*- coding: UTF-8 -*-

# Copyright 2007-2008 VEB IT

# See COPYING for distribution information.

# $Id$

"""The main class for vmm."""

from constants.VERSION import VERSION

__author__ = 'Pascal Volk <p.volk@veb-it.de>'

__version__ = VERSION

__revision__ = 'rev '+'$Rev$'.split()[1]

__date__ = '$Date$'.split()[1]

import os

import re

import sys

from encodings.idna import ToASCII, ToUnicode

from getpass import getpass

from shutil import rmtree

from subprocess import Popen, PIPE

from pyPgSQL import PgSQL # python-pgsql - http://pypgsql.sourceforge.net

from Exceptions import *

import constants.ERROR as ERR

from Config import Config as Cfg

from Account import Account

from Alias import Alias

from Domain import Domain

SALTCHARS = './0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'

RE_ASCII_CHARS = """^[\x20-\x7E]*$"""

RE_DOMAIN = """^(?:[a-z0-9-]{1,63}\.){1,}[a-z]{2,6}$"""

RE_DOMAIN_SRCH = """^[a-z0-9-\.]+$"""

RE_LOCALPART = """[^\w!#$%&'\*\+-\.\/=?^_`{\|}~]"""

RE_MAILLOCATION = """^[\w]{1,20}$"""

class VirtualMailManager:

    """The main class for vmm"""

    def __init__(self):

        """Creates a new VirtualMailManager instance.

        Throws a VMMNotRootException if your uid is greater 0.

        """

        self.__cfgFileName = '/usr/local/etc/vmm.cfg'

        self.__permWarnMsg = _(u"fix permissions for »%s«\n`chmod 0600 %s`\

 would be great.") % (self.__cfgFileName, self.__cfgFileName)

        self.__warnings = []

        self.__Cfg = None

        self.__dbh = None

        if os.geteuid():

            raise VMMNotRootException(_(u"You are not root.\n\tGood bye!\n"),

                ERR.CONF_NOPERM)

        if self.__chkCfgFile():

            self.__Cfg = Cfg(self.__cfgFileName)

            self.__Cfg.load()

            self.__Cfg.check()

            self.__cfgSections = self.__Cfg.getsections()

            self.__scheme = self.__Cfg.get('misc', 'passwdscheme')

        if not sys.argv[1] in ['cf', 'configure']:

            self.__chkenv()

    def __chkCfgFile(self):

        """Checks the configuration file, returns bool"""

        if not os.path.isfile(self.__cfgFileName):

            raise VMMException(_(u"The file »%s« does not exists.") %

                self.__cfgFileName, ERR.CONF_NOFILE)

        fstat = os.stat(self.__cfgFileName)

        fmode = int(oct(fstat.st_mode & 0777))

        if fmode % 100 and fstat.st_uid != fstat.st_gid \

        or fmode % 10 and fstat.st_uid == fstat.st_gid:

            raise VMMPermException(self.__permWarnMsg, ERR.CONF_ERROR)

        else:

            return True

    def __chkenv(self):

        """"""

        if not os.path.exists(self.__Cfg.get('domdir', 'base')):

            old_umask = os.umask(0006)

            os.makedirs(self.__Cfg.get('domdir', 'base'), 0771)

            os.chown(self.__Cfg.get('domdir', 'base'), 0,

                    self.__Cfg.getint('misc', 'gid_mail'))

            os.umask(old_umask)

        elif not os.path.isdir(self.__Cfg.get('domdir', 'base')):

            raise VMMException(_(u'»%s« is not a directory.\n\

(vmm.cfg: section "domdir", option "base")') %

                self.__Cfg.get('domdir', 'base'), ERR.NO_SUCH_DIRECTORY)

        for opt, val in self.__Cfg.items('bin'):

            if not os.path.exists(val):

                raise VMMException(_(u'»%s« doesn\'t exists.\n\

(vmm.cfg: section "bin", option "%s")') %

                    (val, opt), ERR.NO_SUCH_BINARY)

            elif not os.access(val, os.X_OK):

                raise VMMException(_(u'»%s« is not executable.\n\

(vmm.cfg: section "bin", option "%s")') %

                    (val, opt), ERR.NOT_EXECUTABLE)

    def __dbConnect(self):

        """Creates a pyPgSQL.PgSQL.connection instance."""

        try:

            self.__dbh = PgSQL.connect(

                    database=self.__Cfg.get('database', 'name'),

                    user=self.__Cfg.get('database', 'user'),

                    host=self.__Cfg.get('database', 'host'),

                    password=self.__Cfg.get('database', 'pass'),

                    client_encoding='utf8', unicode_results=True)

            dbc = self.__dbh.cursor()

            dbc.execute("SET NAMES 'UTF8'")

            dbc.close()

        except PgSQL.libpq.DatabaseError, e:

            raise VMMException(str(e), ERR.DATABASE_ERROR)

    def chkLocalpart(localpart):

        """Validates the local part of an e-mail address.

        Keyword arguments:

        localpart -- the e-mail address that should be validated (str)

        """

        if len(localpart) < 1:

            raise VMMException(_(u'No localpart specified.'),

                ERR.LOCALPART_INVALID)

        if len(localpart) > 64:

            raise VMMException(_(u'The local part »%s« is too long') %

                localpart, ERR.LOCALPART_TOO_LONG)

        ic = re.compile(RE_LOCALPART).findall(localpart)

        if len(ic):

            ichrs = ''

            for c in set(ic):

                ichrs += u"»%s« " % c

            raise VMMException(

                _(u"The local part »%s« contains invalid characters: %s") %

                (localpart, ichrs), ERR.LOCALPART_INVALID)

        return localpart

    chkLocalpart = staticmethod(chkLocalpart)

    def idn2ascii(domainname):

        """Converts an idn domainname in punycode.

        Keyword arguments:

        domainname -- the domainname to convert (str)

        """

        tmp = []

        for label in domainname.split('.'):

            if len(label) == 0:

                continue

            tmp.append(ToASCII(label))

        return '.'.join(tmp)

    idn2ascii = staticmethod(idn2ascii)

    def ace2idna(domainname):

        """Convertis a domainname from ACE according to IDNA

        Keyword arguments:

        domainname -- the domainname to convert (str)

        """

        tmp = []

        for label in domainname.split('.'):

            if len(label) == 0:

                continue

            tmp.append(ToUnicode(label))

        return '.'.join(tmp)

    ace2idna = staticmethod(ace2idna)

    def chkDomainname(domainname):

        """Validates the domain name of an e-mail address.

        Keyword arguments:

        domainname -- the domain name that should be validated

        """

        re.compile(RE_ASCII_CHARS)

        if not re.match(RE_ASCII_CHARS, domainname):

            domainname = VirtualMailManager.idn2ascii(domainname)

        if len(domainname) > 255:

            raise VMMException(_(u'The domain name is too long.'),

                ERR.DOMAIN_TOO_LONG)

        re.compile(RE_DOMAIN)

        if not re.match(RE_DOMAIN, domainname):

            raise VMMException(_(u'The domain name is invalid.'),

                ERR.DOMAIN_INVALID)

        return domainname

    chkDomainname = staticmethod(chkDomainname)

    def chkEmailAddress(address):

        try:

            localpart, domain = address.split('@')

        except ValueError:

            raise VMMException(_(u"Missing '@' sign in e-mail address »%s«.") %

                address, ERR.INVALID_ADDRESS)

        except AttributeError:

            raise VMMException(_(u"»%s« looks not like an e-mail address.") %

                address, ERR.INVALID_ADDRESS)

        domain = VirtualMailManager.chkDomainname(domain)

        localpart = VirtualMailManager.chkLocalpart(localpart)

        return '%s@%s' % (localpart, domain)

    chkEmailAddress = staticmethod(chkEmailAddress)

    def __getAccount(self, address, password=None):

        self.__dbConnect()

        if not password is None:

            password = self.__pwhash(password)

        return Account(self.__dbh, address, password)

    def _readpass(self):

        clear0 = ''

        clear1 = '1'

        while clear0 != clear1:

            while len(clear0) < 1:

                clear0 = getpass(prompt=_('Enter new password: '))

                if len(clear0) < 1:

                    sys.stderr.write('%s\n'

                            % _('Sorry, empty passwords are not permitted'))

            clear1 = getpass(prompt=_('Retype new password: '))

            if clear0 != clear1:

                clear0 = ''

                sys.stderr.write('%s\n' % _('Sorry, passwords do not match'))

        return clear0

    def __getAlias(self, address, destination=None):

        address = VirtualMailManager.chkEmailAddress(address)

        if not destination is None:

            if destination.count('@'):

                destination = VirtualMailManager.chkEmailAddress(destination)

            else:

                destination = VirtualMailManager.chkLocalpart(destination)

        self.__dbConnect()

        return Alias(self.__dbh, address, destination)

    def __getDomain(self, domainname, transport=None):

        if transport is None:

            transport = self.__Cfg.get('misc', 'transport')

        self.__dbConnect()

        return Domain(self.__dbh, domainname,

                self.__Cfg.get('domdir', 'base'), transport)

    def __getDiskUsage(self, directory):

        """Estimate file space usage for the given directory.

        Keyword arguments:

        directory -- the directory to summarize recursively disk usage for

        """

        if self.__isdir(directory):

            return Popen([self.__Cfg.get('bin', 'du'), "-hs", directory],

                stdout=PIPE).communicate()[0].split('\t')[0]

        else:

            return 0

    def __isdir(self, directory):

        isdir = os.path.isdir(directory)

        if not isdir:

            self.__warnings.append(_('No such directory: %s') % directory)

        return isdir

    def __makedir(self, directory, mode=None, uid=None, gid=None):

        if mode is None:

            mode = self.__Cfg.getint('maildir', 'mode')

        if uid is None:

            uid = 0

        if gid is None:

            gid = 0

        os.makedirs(directory, mode)

        os.chown(directory, uid, gid)

    def __domdirmake(self, domdir, gid):

        os.umask(0006)

        oldpwd = os.getcwd()

        basedir = self.__Cfg.get('domdir', 'base')

        domdirdirs = domdir.replace(basedir+'/', '').split('/')

        os.chdir(basedir)

        if not os.path.isdir(domdirdirs[0]):

            self.__makedir(domdirdirs[0], 489, 0,

                    self.__Cfg.getint('misc', 'gid_mail'))

        os.chdir(domdirdirs[0])

        os.umask(0007)

        self.__makedir(domdirdirs[1], self.__Cfg.getint('domdir', 'mode'), 0,

                gid)

        os.chdir(oldpwd)

    def __maildirmake(self, domdir, uid, gid):

        """Creates maildirs and maildir subfolders.

        Keyword arguments:

        uid -- user id from the account

        gid -- group id from the account

        """

        os.umask(0007)

        oldpwd = os.getcwd()

        os.chdir(domdir)

        maildir = '%s' % self.__Cfg.get('maildir', 'folder')

        folders = [maildir , maildir+'/.Drafts', maildir+'/.Sent',

                maildir+'/.Templates', maildir+'/.Trash']

        subdirs = ['cur', 'new', 'tmp']

        mode = self.__Cfg.getint('maildir', 'mode')

        self.__makedir('%s' % uid, mode, uid, gid)

        os.chdir('%s' % uid)

        for folder in folders:

            self.__makedir(folder, mode, uid, gid)

            for subdir in subdirs:

                self.__makedir(folder+'/'+subdir, mode, uid, gid)

        os.chdir(oldpwd)

    def __maildirdelete(self, domdir, uid, gid):

        if uid > 0 and gid > 0:

            maildir = '%s' % uid

            if maildir.count('..') or domdir.count('..'):

                raise VMMException(_(u'Found ".." in maildir path.'),

                    ERR.FOUND_DOTS_IN_PATH)

            if os.path.isdir(domdir):

                os.chdir(domdir)

                if os.path.isdir(maildir):

                    mdstat = os.stat(maildir)

                    if (mdstat.st_uid, mdstat.st_gid) != (uid, gid):

                        raise VMMException(

                          _(u'Owner/group mismatch in maildir detected.'),

                          ERR.MAILDIR_PERM_MISMATCH)

                    rmtree(maildir, ignore_errors=True)

                else:

                    raise VMMException(_(u"No such directory: %s/%s") %

                        (domdir, uid), ERR.NO_SUCH_DIRECTORY)

    def __domdirdelete(self, domdir, gid):

        if gid > 0:

            if not self.__isdir(domdir):

                return

            basedir = '%s' % self.__Cfg.get('domdir', 'base')

            domdirdirs = domdir.replace(basedir+'/', '').split('/')

            if basedir.count('..') or domdir.count('..'):

                raise VMMException(

                        _(u'FATAL: ".." in domain directory path detected.'),

                            ERR.FOUND_DOTS_IN_PATH)

            if os.path.isdir('%s/%s' % (basedir, domdirdirs[0])):

                os.chdir('%s/%s' % (basedir, domdirdirs[0]))

                if os.lstat(domdirdirs[1]).st_gid != gid:

                    raise VMMException(

                    _(u'FATAL: group mismatch in domain directory detected'),

                        ERR.DOMAINDIR_GROUP_MISMATCH)

                rmtree(domdirdirs[1], ignore_errors=True)

    def __getSalt(self):

        from random import choice

        salt = None

        if self.__scheme == 'CRYPT':

            salt = '%s%s' % (choice(SALTCHARS), choice(SALTCHARS))

        elif self.__scheme in ['MD5', 'MD5-CRYPT']:

            salt = '$1$'

            for i in range(8):

                salt += choice(SALTCHARS)

            salt += '$'

        return salt

    def __pwCrypt(self, password):

        # for: CRYPT, MD5 and MD5-CRYPT

        from crypt import crypt

        return crypt(password, self.__getSalt())

    def __pwSHA1(self, password):

        # for: SHA/SHA1

        import sha

        from base64 import standard_b64encode