from django.conf import settings
from django.http import HttpResponse, JsonResponse
from django.urls import reverse
from lemoncurry.utils import load_package_json, origin
from urllib.parse import urljoin
from xrd import XRD, Attribute, Element, Link


def add_links(request, dest):
    base = origin(request)
    pkg = load_package_json()
    webfinger = reverse("wellknowns:webfinger") + "?resource={uri}"
    license = "https://creativecommons.org/licenses/by-sa/4.0/"

    links = (
        Link(
            href=urljoin(base, reverse("entries:atom")),
            rel="alternate",
            type_="application/atom+xml",
        ),
        Link(
            href=urljoin(base, reverse("entries:rss")),
            rel="alternate",
            type_="application/rss+xml",
        ),
        Link(
            href=urljoin(base, reverse("lemonauth:indie")), rel="authorization_endpoint"
        ),
        Link(href=pkg["repository"], type_="text/html", rel="code-repository"),
        Link(href=settings.PUSH_HUB, rel="hub"),
        Link(href=license, type_="text/html", rel="license"),
        Link(href=license + "rdf", type_="application/rdf+xml", rel="license"),
        Link(
            template=urljoin(base, webfinger),
            type_="application/json",
            rel="lrdd",
        ),
        Link(
            href=urljoin(base, reverse("wellknowns:manifest")),
            rel="manifest",
            type_="application/json",
        ),
        Link(href=urljoin(base, reverse("micropub:micropub")), rel="micropub"),
        Link(href=urljoin(base, reverse("lemonauth:token")), rel="token_endpoint"),
        Link(href="https://openid.indieauth.com/openid", rel="openid.server"),
        Link(href=base, rel="openid.delegate"),
    )
    dest.extend(links)


def host_meta(request):
    h = XRD(subject="https://" + request.site.domain)
    add_links(request, h.links)
    return h


def host_meta_xml(request):
    return HttpResponse(
        host_meta(request).to_xml().toprettyxml(indent="  ", encoding="utf-8"),
        content_type="application/xrd+xml",
    )


# The XRD package doesn't actually generate correct JSON, so we have to do it
# ourselves instead.
def host_meta_json(request):
    meta = host_meta(request)
    links = []
    for l in meta.links:
        link = {
            "rel": l.rel,
            "type": l.type,
            "href": l.href,
            "template": l.template,
        }
        for k in list(link.keys()):
            if not link[k]:
                del link[k]
        links.append(link)

    meta = {"links": links, "subject": meta.subject}
    return JsonResponse(meta)