"""

Internationalization support.

"""

import warnings

from os import path



from django.utils.encoding import force_unicode

from django.utils.functional import lazy

from django.utils.importlib import import_module





__all__ = ['gettext', 'gettext_noop', 'gettext_lazy', 'ngettext',

        'ngettext_lazy', 'string_concat', 'activate', 'deactivate',

        'get_language', 'get_language_bidi', 'get_date_formats',

        'get_partial_date_formats', 'check_for_language', 'to_locale',

        'get_language_from_request', 'templatize', 'ugettext', 'ugettext_lazy',

        'ungettext', 'ungettext_lazy', 'pgettext', 'pgettext_lazy',

        'npgettext', 'npgettext_lazy', 'deactivate_all', 'get_language_info']



# Here be dragons, so a short explanation of the logic won't hurt:

# We are trying to solve two problems: (1) access settings, in particular

# settings.USE_I18N, as late as possible, so that modules can be imported

# without having to first configure Django, and (2) if some other code creates

# a reference to one of these functions, don't break that reference when we

# replace the functions with their real counterparts (once we do access the

# settings).



class Trans(object):

    """

    The purpose of this class is to store the actual translation function upon

    receiving the first call to that function. After this is done, changes to

    USE_I18N will have no effect to which function is served upon request. If

    your tests rely on changing USE_I18N, you can delete all the functions

    from _trans.__dict__.



    Note that storing the function with setattr will have a noticeable

    performance effect, as access to the function goes the normal path,

    instead of using __getattr__.

    """



    def __getattr__(self, real_name):

        from django.conf import settings

        if settings.USE_I18N:

            from django.utils.translation import trans_real as trans

            # Make sure the project's locale dir isn't in LOCALE_PATHS

            if settings.SETTINGS_MODULE is not None:

                parts = settings.SETTINGS_MODULE.split('.')

                project = import_module(parts[0])

                project_locale_path = path.normpath(

                    path.join(path.dirname(project.__file__), 'locale'))

                normalized_locale_paths = [path.normpath(locale_path)

                    for locale_path in settings.LOCALE_PATHS]

                if (path.isdir(project_locale_path) and

                        not project_locale_path in normalized_locale_paths):

                    warnings.warn("Translations in the project directory "

                                  "aren't supported anymore. Use the "

                                  "LOCALE_PATHS setting instead.",

                                  PendingDeprecationWarning)

        else:

            from django.utils.translation import trans_null as trans

        setattr(self, real_name, getattr(trans, real_name))

        return getattr(trans, real_name)



_trans = Trans()



# The Trans class is no more needed, so remove it from the namespace.

del Trans



def gettext_noop(message):

    return _trans.gettext_noop(message)



ugettext_noop = gettext_noop



def gettext(message):

    return _trans.gettext(message)



def ngettext(singular, plural, number):

    return _trans.ngettext(singular, plural, number)



def ugettext(message):

    return _trans.ugettext(message)



def ungettext(singular, plural, number):

    return _trans.ungettext(singular, plural, number)



def pgettext(context, message):

    return _trans.pgettext(context, message)



def npgettext(context, singular, plural, number):

    return _trans.npgettext(context, singular, plural, number)



ngettext_lazy = lazy(ngettext, str)

gettext_lazy = lazy(gettext, str)

ungettext_lazy = lazy(ungettext, unicode)

ugettext_lazy = lazy(ugettext, unicode)

pgettext_lazy = lazy(pgettext, unicode)

npgettext_lazy = lazy(npgettext, unicode)



def activate(language):

    return _trans.activate(language)



def deactivate():

    return _trans.deactivate()



def get_language():

    return _trans.get_language()



def get_language_bidi():

    return _trans.get_language_bidi()



def get_date_formats():

    return _trans.get_date_formats()



def get_partial_date_formats():

    return _trans.get_partial_date_formats()



def check_for_language(lang_code):

    return _trans.check_for_language(lang_code)



def to_locale(language):

    return _trans.to_locale(language)



def get_language_from_request(request):

    return _trans.get_language_from_request(request)



def templatize(src, origin=None):

    return _trans.templatize(src, origin)



def deactivate_all():

    return _trans.deactivate_all()



def _string_concat(*strings):

    """

    Lazy variant of string concatenation, needed for translations that are

    constructed from multiple parts.

    """

    return u''.join([force_unicode(s) for s in strings])

string_concat = lazy(_string_concat, unicode)



def get_language_info(lang_code):

    from django.conf.locale import LANG_INFO

    try:

        return LANG_INFO[lang_code]

    except KeyError:

        raise KeyError("Unknown language code %r." % lang_code)