# -*- coding: utf-8 -*-

from django import VERSION
from django.utils.http import is_safe_url
from django.http import HttpResponseRedirect
from django.views.decorators.cache import never_cache

from .models import Currency
from .conf import SESSION_KEY


def _is_safe_url(url, allowed_hosts, **kwargs):
    if VERSION < (1, 11, 0):
        host = allowed_hosts[0]
        return is_safe_url(url, host=host)
    else:
        return is_safe_url(url, allowed_hosts=allowed_hosts, **kwargs)


@never_cache
def set_currency(request):
    next, currency_code = (
        request.POST.get('next') or request.GET.get('next'),
        request.POST.get('currency_code', None) or
        request.GET.get('currency_code', None))

    if not _is_safe_url(next, [request.get_host()]):
        next = request.META.get('HTTP_REFERER')
        if not _is_safe_url(next, [request.get_host()]):
            next = '/'

    response = HttpResponseRedirect(next)
    if currency_code and Currency.active.filter(code=currency_code).exists():
        # Set cookie irrespective for page cache visibility
        response.set_cookie(SESSION_KEY, currency_code)
        if hasattr(request, 'session'):
            request.session[SESSION_KEY] = currency_code
    return response