Add AK owner links to wiki export

This will try to automatically detect whether wiki or external links were used
Implements #90

AKModel/templates/admin/AKModel/wiki_export.html

 {% extends "admin/base_site.html" %}
 
+{% load tags_AKModel %}
+
 {% block content %}
 
 {% regroup AKs by category as ak_list %}
@@ -12,7 +14,7 @@
 | name={{ ak.name }}
 | beschreibung= {{ ak.description }}
 | wieviele={{ ak.interest_counter }}
-| wer={{ ak.owners_list }}
+| wer={{ ak.owners|wiki_owners_export:ak.event }}
 | wann=
 | dauer={{ ak.durations_list }}
 | reso={{ ak.reso }}

AKModel/templatetags/tags_AKModel.py

@@ -25,3 +25,17 @@ def message_bootstrap_class(tag):
     elif tag == "warning":
         return "alert-warning"
     return "alert-info"
+
+
+@register.filter
+def wiki_owners_export(owners, event):
+    def to_link(owner):
+        if owner.link != '':
+            event_link_prefix, _ = event.base_url.rsplit("/", 1)
+            link_prefix, link_end = owner.link.rsplit("/", 1)
+            if event_link_prefix == link_prefix:
+                return f"[[{link_end}|{str(owner)}]]"
+            return f"[{owner.link} {str(owner)}]"
+        return str(owner)
+
+    return ", ".join(to_link(owner) for owner in owners.all())