#!/usr/bin/env python

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

# opyright 2007-2008 VEB IT

# See COPYING for distribution information.

# $Id$

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

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

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

import os

import re

import sys

from encodings.idna import ToASCII, ToUnicode

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 VMMConfig as Cfg

from Account import Account

from Alias import Alias

from Domain import Domain

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

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

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

re.compile(RE_ASCII_CHARS)

re.compile(RE_DOMAIN)

ENCODING_IN = sys.getfilesystemencoding()

ENCODING_OUT = sys.stdout.encoding or sys.getfilesystemencoding()

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 = "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(("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.__chkenv()

    def __chkCfgFile(self):

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

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

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

                self.__cfgFileName, ERR.CONF_NOFILE))

        fstat = os.stat(self.__cfgFileName)

        try:

            fmode = self.__getFileMode()

        except:

            raise

        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('maildir', 'base')):

            old_umask = os.umask(0007)

            os.makedirs(self.__Cfg.get('maildir', 'base'), 0770)

            os.umask(old_umask)

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

            raise VMMException(('%s is not a directory' %

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

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

            if not os.path.exists(val):

                raise VMMException(("%s doesn't exists.", ERR.NO_SUCH_BINARY))

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

                raise VMMException(("%s is not executable.", ERR.NOT_EXECUTABLE))

    def __getFileMode(self):

        """Determines the file access mode from file __cfgFileName,

        returns int.

        """

        try:

            return int(oct(os.stat(self.__cfgFileName).st_mode & 0777))

        except:

            raise

    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(self, 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) > 64:

            raise VMMException(('The local part is too long',

                ERR.LOCALPART_TOO_LONG))

        if re.compile(RE_LOCALPART).search(localpart):

            raise VMMException((

                'The local part »%s« contains invalid characters.' % localpart,

                ERR.LOCALPART_INVALID))

        return localpart

    def __idn2ascii(self, 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(unicode(label, ENCODING_IN)))

        return '.'.join(tmp)

    def __ace2idna(self, 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)

    def __chkDomainname(self, domainname):

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

        Keyword arguments:

        domainname -- the domain name that should be validated

        """

        if not re.match(RE_ASCII_CHARS, domainname):

            domainname = self.__idn2ascii(domainname)

        if len(domainname) > 255:

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

                ERR.DOMAIN_TOO_LONG))

        if not re.match(RE_DOMAIN, domainname):

            raise VMMException(('The domain name is invalid.',

                ERR.DOMAIN_INVALID))

        return domainname

    def __chkEmailAddress(self, address):

        try:

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

        except ValueError:

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

                address, ERR.INVALID_ADDRESS))

        except AttributeError:

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

                address, ERR.INVALID_ADDRESS))

        domain = self.__chkDomainname(domain)

        localpart = self.__chkLocalpart(localpart)

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

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

        address = self.__chkEmailAddress(address)

        self.__dbConnect()

        if not password is None:

            password = self.__pwhash(password)

        return Account(self.__dbh, self.__Cfg.get('maildir', 'base'), address,

                password)

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

        address = self.__chkEmailAddress(address)

        if not destination is None:

            if destination.count('@'):

                destination = self.__chkEmailAddress(destination)

            else:

                destination = self.__chkLocalpart(destination)

        self.__dbConnect()

        return Alias(self.__dbh, address, self.__Cfg.get('maildir', 'base'),

                destination)

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

        domainname = self.__chkDomainname(domainname)

        self.__dbConnect()

        return Domain(self.__dbh, domainname,

                self.__Cfg.get('maildir', '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

        """

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

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

    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('maildir', '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(('FATAL: ".." in maildir path detected.',

                    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(

                            ('FATAL: owner/group mismatch in maildir detected',

                                ERR.MAILDIR_PERM_MISMATCH))

                    rmtree(maildir, ignore_errors=True)

    def __domdirdelete(self, domdir, gid):

        if gid > 0:

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

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

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

                raise VMMException(

                        ('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(

                    ('FATAL: group mismatch in domain directory detected',

                        ERR.DOMAINDIR_GROUP_MISMATCH))

                rmtree(domdirdirs[1], ignore_errors=True)

    def __pwhash(self, password, scheme=None, user=None):

        # XXX alle Schemen berücksichtigen XXX

        if scheme is None:

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

        return Popen([self.__Cfg.get('bin', 'dovecotpw'), '-s', scheme, '-p',

            password], stdout=PIPE).communicate()[0][len(scheme)+2:-1]

    def hasWarnings(self):

        """Checks if warnings are present, returns bool."""

        return bool(len(self.__warnings))

    def getWarnings(self):

        """Returns a list with all available warnings."""

        return self.__warnings

    def setupIsDone(self):

        """Checks if vmm is configured, returns bool"""

        try:

            return self.__Cfg.getboolean('config', 'done')

        except ValueError, e:

            raise VMMConfigException('Configurtion error: "'+str(e)

                +'"\n(in section "Connfig", option "done")'

                +'\nsee also: vmm.cfg(5)\n')

    def configure(self, section=None):

        """Starts interactive configuration.

        Configures in interactive mode options in the given section.

        If no section is given (default) all options from all sections

        will be prompted.

        Keyword arguments:

        section -- the section to configure (default None):

            'database', 'maildir', 'bin' or 'misc'

        """

        try:

            if not section:

                self.__Cfg.configure(self.__cfgSections)

            elif section not in self.__cfgSections:

                raise VMMException(("Invalid section: »%s«" % section,

                    ERR.INVALID_SECTION))

            else:

                self.__Cfg.configure([section])

        except:

            raise

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

        dom = self.__getDomain(domainname, transport)

        dom.save()

        self.__domdirmake(dom.getDir(), dom.getID())

    def domain_transport(self, domainname, transport):

        dom = self.__getDomain(domainname, None)

        dom.updateTransport(transport)

    def domain_delete(self, domainname, force=None):

        if not force is None and force not in ['deluser','delalias','delall']:

            raise VMMDomainException(('Invalid argument: «%s»' % force,

                ERR.INVALID_OPTION))

        dom = self.__getDomain(domainname)

        gid = dom.getID()

        domdir = dom.getDir()

        if self.__Cfg.getboolean('misc', 'forcedel') or force == 'delall':

            dom.delete(True, True)

        elif force == 'deluser':

            dom.delete(delUser=True)

        elif force == 'delalias':

            dom.delete(delAlias=True)

        else:

            dom.delete()

        if self.__Cfg.getboolean('domdir', 'delete'):

            self.__domdirdelete(domdir, gid)