from django.http import HttpResponse


# Create your views here.

def index(request):
    back_to_url = ""
    if "back_to" in request.GET:
        back_to_url = request.GET["back_to"]
    elif 'HTTP_HOST' in request.META:
        back_to_url = request.META['HTTP_HOST']
    if back_to_url != "":
        return HttpResponse(
            """Sorry, <a href="{domain}">this part of domain</a> is not reachable by IPv4.
            Please upgrade to IPv6 and try to reach {domain} again.""".format(
                domain=back_to_url
            )
        )
    else:
        return HttpResponse(
            """Sorry, this part of domain is not reachable by IPv4.
            Please upgrade to IPv6 and try to reach the domain again."""
        )