from django import http

from django.utils.translation import check_for_language, activate, to_locale, get_language

from django.utils.text import javascript_quote

from django.conf import settings

import os

import gettext as gettext_module

def set_language(request):

    """

    Redirect to a given url while setting the chosen language in the

    session or cookie. The url and the language code need to be

    specified in the request parameters.

    Since this view changes how the user will see the rest of the site, it must

    only be accessed as a POST request. If called as a GET request, it will

    redirect to the page in the request (the 'next' parameter) without changing

    any state.

    """

    next = request.REQUEST.get('next', None)

    if not next:

        next = request.META.get('HTTP_REFERER', None)

    if not next:

        next = '/'

    response = http.HttpResponseRedirect(next)

    if request.method == 'POST':

        lang_code = request.POST.get('language', None)

        if lang_code and check_for_language(lang_code):

            if hasattr(request, 'session'):

                request.session['django_language'] = lang_code

            else:

                response.set_cookie(settings.LANGUAGE_COOKIE_NAME, lang_code)

    return response

NullSource = """

/* gettext identity library */

function gettext(msgid) { return msgid; }

function ngettext(singular, plural, count) { return (count == 1) ? singular : plural; }

function gettext_noop(msgid) { return msgid; }

"""

LibHead = """

/* gettext library */

var catalog = new Array();

"""

LibFoot = """

function gettext(msgid) {

  var value = catalog[msgid];

  if (typeof(value) == 'undefined') {

    return msgid;

  } else {

    return (typeof(value) == 'string') ? value : value[0];

  }

}

function ngettext(singular, plural, count) {

  value = catalog[singular];

  if (typeof(value) == 'undefined') {

    return (count == 1) ? singular : plural;

  } else {

    return value[pluralidx(count)];

  }

}

function gettext_noop(msgid) { return msgid; }

"""

SimplePlural = """

function pluralidx(count) { return (count == 1) ? 0 : 1; }

"""

InterPolate = r"""

function interpolate(fmt, obj, named) {

  if (named) {

    return fmt.replace(/%\(\w+\)s/g, function(match){return String(obj[match.slice(2,-2)])});

  } else {

    return fmt.replace(/%s/g, function(match){return String(obj.shift())});

  }

}

"""

PluralIdx = r"""

function pluralidx(n) {

  var v=%s;

  if (typeof(v) == 'boolean') {

    return v ? 1 : 0;

  } else {

    return v;

  }

}

"""

def null_javascript_catalog(request, domain=None, packages=None):

    """

    Returns "identity" versions of the JavaScript i18n functions -- i.e.,

    versions that don't actually do anything.

    """

    return http.HttpResponse(NullSource + InterPolate, 'text/javascript')

def javascript_catalog(request, domain='djangojs', packages=None):

    """

    Returns the selected language catalog as a javascript library.

    Receives the list of packages to check for translations in the

    packages parameter either from an infodict or as a +-delimited

    string from the request. Default is 'django.conf'.

    Additionally you can override the gettext domain for this view,

    but usually you don't want to do that, as JavaScript messages

    go to the djangojs domain. But this might be needed if you

    deliver your JavaScript source from Django templates.

    """

    if request.GET:

        if 'language' in request.GET:

            if check_for_language(request.GET['language']):

                activate(request.GET['language'])

    if packages is None:

        packages = ['django.conf']

    if type(packages) in (str, unicode):

        packages = packages.split('+')

    packages = [p for p in packages if p == 'django.conf' or p in settings.INSTALLED_APPS]

    default_locale = to_locale(settings.LANGUAGE_CODE)

    locale = to_locale(get_language())

    t = {}

    paths = []

    # first load all english languages files for defaults

    for package in packages:

        p = __import__(package, {}, {}, [''])

        path = os.path.join(os.path.dirname(p.__file__), 'locale')

        paths.append(path)

        try:

            catalog = gettext_module.translation(domain, path, ['en'])

            t.update(catalog._catalog)

        except IOError:

            # 'en' catalog was missing. This is harmless.

            pass

    # next load the settings.LANGUAGE_CODE translations if it isn't english

    if default_locale != 'en':

        for path in paths:

            try:

                catalog = gettext_module.translation(domain, path, [default_locale])

            except IOError:

                catalog = None

            if catalog is not None:

                t.update(catalog._catalog)

    # last load the currently selected language, if it isn't identical to the default.

    if locale != default_locale:

        for path in paths:

            try:

                catalog = gettext_module.translation(domain, path, [locale])

            except IOError:

                catalog = None

            if catalog is not None:

                t.update(catalog._catalog)

    src = [LibHead]

    plural = None

    if '' in t:

        for l in t[''].split('\n'):

            if l.startswith('Plural-Forms:'):

                plural = l.split(':',1)[1].strip()

    if plural is not None:

        # this should actually be a compiled function of a typical plural-form:

        # Plural-Forms: nplurals=3; plural=n%10==1 && n%100!=11 ? 0 : n%10>=2 && n%10<=4 && (n%100<10 || n%100>=20) ? 1 : 2;

        plural = [el.strip() for el in plural.split(';') if el.strip().startswith('plural=')][0].split('=',1)[1]

        src.append(PluralIdx % plural)

    else:

        src.append(SimplePlural)

    csrc = []

    pdict = {}

    for k, v in t.items():

        if k == '':

            continue

        if type(k) in (str, unicode):

            csrc.append("catalog['%s'] = '%s';\n" % (javascript_quote(k), javascript_quote(v)))

        elif type(k) == tuple:

            if k[0] not in pdict:

                pdict[k[0]] = k[1]

            else:

                pdict[k[0]] = max(k[1], pdict[k[0]])

            csrc.append("catalog['%s'][%d] = '%s';\n" % (javascript_quote(k[0]), k[1], javascript_quote(v)))

        else:

            raise TypeError, k

    csrc.sort()

    for k,v in pdict.items():

        src.append("catalog['%s'] = [%s];\n" % (javascript_quote(k), ','.join(["''"]*(v+1))))

    src.extend(csrc)

    src.append(LibFoot)

    src.append(InterPolate)

    src = ''.join(src)

    return http.HttpResponse(src, 'text/javascript')