public static byte[] Write_wdata_links(List_adp slink_list, Xowe_wiki wiki, Xoa_ttl ttl, Wdata_external_lang_links_data external_links_mgr) {
		try {
			switch (wiki.Domain_tid()) {
				case Xow_domain_type_.Tid_home:		// home will never be in wikidata
				case Xow_domain_type_.Tid_wikidata:	// wikidata will never be in wikidata
					return Qid_null;
			}
			Wdata_wiki_mgr wdata_mgr = wiki.Appe().Wiki_mgr().Wdata_mgr();
			Wdata_doc doc = wdata_mgr.Pages_get(wiki, ttl); if (doc == null) return Qid_null;	// no links
			boolean external_links_mgr_enabled = external_links_mgr.Enabled();
			Ordered_hash links = doc.Slink_list();
			Bry_bfr tmp_bfr = wiki.Appe().Utl__bfr_mkr().Get_k004();
			Xow_wiki_abrv wiki_abrv = new Xow_wiki_abrv();
			int len = links.Count();
			for (int i = 0; i < len; i++) {
				Wdata_sitelink_itm slink = (Wdata_sitelink_itm)links.Get_at(i);
				byte[] xwiki_key = slink.Site();
				Xow_wiki_abrv_.parse_(wiki_abrv, xwiki_key, 0, xwiki_key.length);
				if (wiki_abrv.Domain_tid() == Xow_wiki_abrv_.Tid_null) {
					wiki.Appe().Usr_dlg().Warn_many("", "", "unknown wiki in wikidata: ttl=~{0} wiki=~{1}", ttl.Page_db_as_str(), String_.new_u8(xwiki_key));
					continue;
				}
				if (wiki_abrv.Domain_tid() != wiki.Domain_tid()) continue;	// ignore wikis in a different domain; EX: looking at enwiki:Earth, and wikidata has dewikiquote; ignore dewikiquote; DATE:2014-06-21
				byte[] lang_key = wiki_abrv.Lang_itm().Key();
				if (external_links_mgr_enabled && external_links_mgr.Langs_hide(lang_key, 0, lang_key.length)) continue;
				tmp_bfr.Add(lang_key);
				tmp_bfr.Add_byte(Byte_ascii.Colon);
				tmp_bfr.Add(slink.Name());
				Xoa_ttl slink_ttl = Xoa_ttl.parse_(wiki, tmp_bfr.Xto_bry_and_clear());
				if (slink_ttl == null) continue;								// invalid ttl
				Xow_xwiki_itm xwiki_itm = slink_ttl.Wik_itm();
				if (	xwiki_itm == null									// not a known xwiki; EX: [[zzz:abc]]
					||	Bry_.Eq(xwiki_itm.Domain_bry(), wiki.Domain_bry())	// skip if same as self; i.e.: do not include links to enwiki if already in enwiki
					) continue;
				slink.Page_ttl_(slink_ttl);
				slink_list.Add(slink);
			}
			tmp_bfr.Mkr_rls();
			if (external_links_mgr_enabled && external_links_mgr.Sort())
				slink_list.Sort_by(Xoa_ttl_sorter._);
			return doc.Qid();
		} catch (Exception e) {Err_.Noop(e); return Qid_null;}
	}
 private static boolean Navigate(
     Gfo_usr_dlg usr_dlg,
     Xoae_app app,
     Wdata_wiki_mgr wdata_mgr,
     Xoae_page page,
     byte[] site_bry,
     byte[] page_bry) {
   page_bry =
       Xoa_app_.Utl__encoder_mgr()
           .Http_url()
           .Decode(page_bry); // NOTE: space is converted to + on postback to url; decode
   byte[] wiki_domain = Xow_wiki_alias.Parse_wmf_key(site_bry);
   if (wiki_domain == null) {
     usr_dlg.Warn_many("", "", "site_bry parse failed; site_bry:~{0}", String_.new_u8(site_bry));
     return false;
   }
   Xowe_wiki wiki = app.Wiki_mgr().Get_by_key_or_make(wiki_domain);
   if (wiki == null) {
     usr_dlg.Warn_many(
         "", "", "wiki_domain does not exist; wiki_domain:~{0}", String_.new_u8(wiki_domain));
     return false;
   }
   Xoa_ttl wdata_ttl = Xoa_ttl.parse_(wiki, page_bry);
   if (wdata_ttl == null) {
     usr_dlg.Warn_many("", "", "ttl is invalid; ttl:~{0}", String_.new_u8(page_bry));
     return false;
   }
   Wdata_doc doc = wdata_mgr.Pages_get(wiki, wdata_ttl);
   if (doc == null) {
     usr_dlg.Warn_many(
         "", "", "ttl cannot be found in wikidata; ttl:~{0}", String_.new_u8(wdata_ttl.Raw()));
     return false;
   }
   byte[] qid_bry = doc.Qid();
   Xoae_page qid_page = wdata_mgr.Wdata_wiki().Data_mgr().Redirect(page, qid_bry);
   if (qid_page.Missing()) {
     usr_dlg.Warn_many(
         "", "", "qid cannot be found in wikidata; qid:~{0}", String_.new_u8(qid_bry));
     return false;
   }
   return true;
 }
	public void Init_page_create(Xowe_wiki wiki, String ttl, String txt) {
		Xoa_ttl page_ttl = Xoa_ttl.parse_(wiki, Bry_.new_u8(ttl));
		byte[] page_raw = Bry_.new_u8(txt);
		wiki.Db_mgr().Save_mgr().Data_create(page_ttl, page_raw);
	}