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

# Copyright (c) 2007 - 2010, Pascal Volk

# See COPYING for distribution information.

"""

    VirtualMailManager

    VirtualMailManager package initialization code

"""

import gettext

import os

import re

import locale

from encodings.idna import ToASCII, ToUnicode

from VirtualMailManager.constants.ERROR import \

     DOMAIN_INVALID, DOMAIN_TOO_LONG, LOCALPART_INVALID, LOCALPART_TOO_LONG, \

     NOT_EXECUTABLE, NO_SUCH_BINARY, NO_SUCH_DIRECTORY

from VirtualMailManager.constants.version import __author__, __date__, \

     __version__

from VirtualMailManager.errors import VMMError

__all__ = [

    # version information from VERSION

    '__author__', '__date__', '__version__',

    # defined stuff

    'ENCODING', 'ace2idna', 'check_domainname', 'check_localpart', 'exec_ok',

    'expand_path', 'get_unicode', 'idn2ascii', 'is_dir',

]

# Try to set all of the locales according to the current

# environment variables and get the character encoding.

try:

    locale.setlocale(locale.LC_ALL, '')

except locale.Error:

    locale.setlocale(locale.LC_ALL, 'C')

ENCODING = locale.nl_langinfo(locale.CODESET)

# there may be many domain and e-mail address checks

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

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

gettext.install('vmm', '/usr/local/share/locale', unicode=1)

_ = lambda msg: msg

def get_unicode(string):

    """Converts `string` to `unicode`, if necessary."""

    if isinstance(string, unicode):

        return string

    return unicode(string, ENCODING, 'replace')

def expand_path(path):

    """Expands paths, starting with ``.`` or ``~``, to an absolute path."""

    if path.startswith('.'):

        return os.path.abspath(path)

    if path.startswith('~'):

        return os.path.expanduser(path)

    return path

def is_dir(path):

    """Checks if `path` is a directory.

    Throws a `VMMError` if `path` is not a directory.

    """

    path = expand_path(path)

    if not os.path.isdir(path):

        raise VMMError(_(u"'%s' is not a directory") % get_unicode(path),

                       NO_SUCH_DIRECTORY)

    return path

def exec_ok(binary):

    """Checks if the `binary` exists and if it is executable.

    Throws a `VMMError` if the `binary` isn't a file or is not

    executable.

    """

    binary = expand_path(binary)

    if not os.path.isfile(binary):

        raise VMMError(_(u"'%s' is not a file") % get_unicode(binary),

                       NO_SUCH_BINARY)

    if not os.access(binary, os.X_OK):

        raise VMMError(_(u"File is not executable: '%s'") % 

                       get_unicode(binary), NOT_EXECUTABLE)

    return binary

def idn2ascii(domainname):

    """Converts the idn domain name `domainname` into punycode."""

    return '.'.join([ToASCII(lbl) for lbl in domainname.split('.') if lbl])

def ace2idna(domainname):

    """Converts the domain name `domainname` from ACE according to IDNA."""

    return u'.'.join([ToUnicode(lbl) for lbl in domainname.split('.') if lbl])

def check_domainname(domainname):

    """Returns the validated domain name `domainname`.

    It also converts the name of the domain from IDN to ASCII, if

    necessary.

    Throws an `VMMError`, if the domain name is too long or doesn't

    look like a valid domain name (label.label.label).

    """

    if not RE_DOMAIN.match(domainname):

        domainname = idn2ascii(domainname)

    if len(domainname) > 255:

        raise VMMError(_(u'The domain name is too long'), DOMAIN_TOO_LONG)

    if not RE_DOMAIN.match(domainname):

        raise VMMError(_(u'The domain name %r is invalid') % domainname,

                       DOMAIN_INVALID)

    return domainname

def check_localpart(localpart):

    """Returns the validated local-part `localpart`.

    Throws a `VMMError` if the local-part is too long or contains

    invalid characters.

    """

    if len(localpart) > 64:

        raise VMMError(_(u"The local-part '%s' is too long") % localpart,

                       LOCALPART_TOO_LONG)

    invalid_chars = set(RE_LOCALPART.findall(localpart))

    if invalid_chars:

        i_chars = u''.join((u'"%s" ' % c for c in invalid_chars))

        raise VMMError(_(u"The local-part '%(l_part)s' contains invalid \

characters: %(i_chars)s") %

                       {'l_part': localpart, 'i_chars': i_chars},

                       LOCALPART_INVALID)

    return localpart

del _