Module:Official website

 localmakeUrl=require('Module:URL')._url

 localp={}

 -- Wrapper for pcall which returns nil on failure.
 localfunctionquickPcall(func)
 localsuccess,result=pcall(func)
 ifsuccessthen
 returnresult
 end
 end

 -- Gets the rank for a Wikidata property table. Returns 1, 0 or -1, in
 -- order of rank.
 localfunctiongetRank(prop)
 localrank=prop.rank
 ifrank=='preferred'then
 return1
 elseifrank=='normal'then
 return0
 elseifrank=='deprecated'then
 return-1
 else
 -- No rank or undefined rank is treated as "normal".
 return0
 end
 end

 -- Finds whether a Wikidata property is qualified as being in English.
 localfunctionisEnglish(prop)
 localret=quickPcall(function()
 fori,langinipairs(prop.qualifiers.P407)do
 iflang.datavalue.value['numeric-id']==1860then
 returntrue
 end
 end
 returnfalse
 end)
 returnret==true
 end

 -- Fetches the official website URL from Wikidata.
 localfetchWikidataUrl
 fetchWikidataUrl=function()
 -- Get objects for all official sites on Wikidata.
 localwebsites=quickPcall(function()
 returnmw.wikibase.getAllStatements(mw.wikibase.getEntityIdForCurrentPage(),'P856')
 end)

 -- Clone the objects in case other code needs them in their original order.
 websites=websitesandmw.clone(websites)or{}

 -- Add the table index to the objects in case it is needed in the sort.
 fori,websiteinipairs(websites)do
 website._index=i
 end

 -- Sort the websites, first by highest rank, and then by websites in the
 -- English language, then by the website's original position in the
 -- property list. When we are done, get the URL from the highest-sorted
 -- object.
 table.sort(websites,function(ws1,ws2)
 localr1=getRank(ws1)
 localr2=getRank(ws2)
 ifr1~=r2then
 returnr1>r2
 end
 locale1=isEnglish(ws1)
 locale2=isEnglish(ws2)
 ife1~=e2then
 returne1
 end
 returnws1._index<ws2._index
 end)
 localurl=quickPcall(function()
 returnwebsites[1].mainsnak.datavalue.value
 end)

 -- Cache the result so that we only do the heavy lifting once per #invoke.
 fetchWikidataUrl=function()
 returnurl
 end

 returnurl
 end

 -- Render the URL link, plus other visible output.
 localfunctionrenderUrl(options)
 ifnotoptions.urlandnotoptions.wikidataurlthen
 localqid=mw.wikibase.getEntityIdForCurrentPage()
 localresult='<strong class="error">'..
 'No URL found. Please specify a URL here or add one to Wikidata.'..
 '</strong>'
 ifqidthen
 result=result..' [[File:OOjs UI icon edit-ltr-progressive.svg |frameless |text-top |10px |alt=Edit this at Wikidata |link=https://www.wikidata.org/wiki/'..qid..'#P856|Edit this at Wikidata]]'
 end
 returnresult
 end
 localret={}
 ret[#ret+1]=string.format(
 '<span class="official-website">%s</span>',
 makeUrl(options.urloroptions.wikidataurl,options.display)
 )
 ifoptions.wikidataurlandnotoptions.urlthen
 localqid=mw.wikibase.getEntityIdForCurrentPage()
 ifqidthen
 ret[#ret+1]='[[File:OOjs UI icon edit-ltr-progressive.svg |frameless |text-top |10px |alt=Edit this at Wikidata |link=https://www.wikidata.org/wiki/'..qid..'#P856|Edit this at Wikidata]]'
 end
 end
 returntable.concat(ret,' ')
 end

 -- Render the tracking category.
 localfunctionrenderTrackingCategory(url,wikidataurl)
 ifmw.title.getCurrentTitle().namespace~=0then
 return''
 end
 localcategory
 ifnoturlandnotwikidataurlthen
 category='Official website missing URL'
 elseifnoturlandwikidataurlthen
 return''
 elseifurlandwikidataurlthen
 ifurl:gsub('/%s*$','')~=wikidataurl:gsub('/%s*$','')then
 category='Official website different in Wikidata and Wikipedia'
 end
 else
 category='Official website not in Wikidata'
 end
 returncategoryandstring.format('[[Category:%s]]',category)or''
 end

 functionp._main(args)
 localurl=args[1]orargs.URLorargs.url
 localwikidataurl=fetchWikidataUrl()
 localformattedUrl=renderUrl{
 url=url,
 wikidataurl=wikidataurl,
 display=args[2]orargs.nameor'Official website'
 }
 returnformattedUrl..renderTrackingCategory(url,wikidataurl)
 end

 functionp.main(frame)
 localargs=require('Module:Arguments').getArgs(frame,{
 wrappers='Template:Official website'
 })
 returnp._main(args)
 end

 returnp