Module:Wikipedia ads

 -------------------------------------------------------------------------------
 -- Module:Wikipedia ads
 --
 -- This module displays a random banner-style advert for a Wikipedia project,
 -- page or process. It implements [[Template:Wikipedia ads]].
 -------------------------------------------------------------------------------

 -- Set constants
 localLIST_MODULE='Module:Wikipedia ads/list'
 localDATA_MODULE='Module:Wikipedia ads/data'

 localp={}
 localwarnings={}

 localfunctionaddWarning(msg)
 table.insert(warnings,msg)
 end

 localfunctionmakeWikilink(page,display)
 returnstring.format('[[%s|%s]]',page,display)
 end

 localfunctionmakeUrlLink(url,display)
 url=tostring(url)
 returnstring.format('[%s %s]',url,display)
 end

 localfunctioncolorText(s,color)
 returnstring.format('<span style="color:%s">%s</span>',color,s)
 end

 localfunctiongetImageData(args)
 -- This function gets an image data from the data module. It also tracks
 -- whether the image data choice was random.
 localdata=mw.loadData(DATA_MODULE)

 localfunctiongetSomeImageData(id,param)
 id=tonumber(id)orid
 localsomeImageData=data.ids[id]
 ifsomeImageDatathen
 returnsomeImageData
 else
 addWarning(string.format("ID '%s' does not exist",tostring(id)))
 returnnil
 end
 end

 -- Get the image data of the ad to display.
 localimageData,isRandom
 ifargs.adthen
 imageData=getSomeImageData(args.ad,'ad')
 ifnotimageDatathen
 returnnil
 end
 isRandom=false
 else
 localimageDataArray,length
 ifargs[1]then
 imageDataArray={}
 fori,idinipairs(args)do
 imageDataArray[#imageDataArray+1]=getSomeImageData(id,i)
 end
 length=#imageDataArray
 iflength<1then
 returnnil
 end
 else
 imageDataArray=data.list
 length=data.noAds
 end
 assert(length>=1,string.format(
 'no ads were found in [[%s]]',
 DATA_MODULE
 ))
 isRandom=length>1
 ifisRandomthen
 math.randomseed(os.clock()*1000000000)
 imageData=imageDataArray[math.random(length)]
 else
 imageData=imageDataArray[1]
 end
 end

 -- Check that the image data has the required fields. We have already
 -- checked the ID in the data module.
 fori,fieldinipairs{'image','link'}do
 assert(imageData[field],string.format(
 "Invalid image data in [[%s]]; table with ID '%s' has no '%s' field",
 LIST_MODULE,tostring(imageData.id),field
 ))
 end

 returnimageData,isRandom
 end

 localfunctionrenderAd(imageData,args,title,isRandom)
 localwidth=tonumber(args.width)or468
 localmaxWidth=width+9
 locallinkColor=args.linkcoloror'#002bb8'

 -- Table root
 localroot=mw.html.create('table')
 root
 :addClass('plainlinks qxz-ads')
 :css('color',args.coloror'#555555')
 :css('border','none')
 :css('background',args.background)
 :css('line-height','1em')
 :css('font-size','90%')
 :css('display','block')
 :css('overflow','auto')
 :css('max-width',maxWidth..'px')
 ifargs.floatthen
 root:css('float',args.float)
 root:css('margin',args.margin)
 else
 root:css('margin',args.marginor'0 auto')
 end

 -- Image row
 root
 :tag('tr')
 :tag('td')
 :attr('colspan',2)
 :css('border','none')
 :wikitext(string.format(
 '[[File:%s|%dpx|alt=Wikipedia ad for %s|link=%s]]',
 imageData.image,
 width,
 imageData.link,
 imageData.link
 ))

 -- Links row
 ifnotargs.nolinksthen
 locallinksRow=root:tag('tr')

 -- Wikipedia ads link
 linksRow
 :tag('td')
 :css('border','none')
 :wikitext(makeWikilink(
 'Template:Wikipedia ads',
 colorText('Wikipedia ads',linkColor)
 ))

 -- File info, purge and ID
 locallinks={}
 links[#links+1]=makeWikilink(
 ':File:'..imageData.image,
 colorText('file info',linkColor)
 )
 ifargs.showpurgeorisRandomthen
 links[#links+1]=makeUrlLink(
 title:fullUrl{action='purge'},
 colorText('show another',linkColor)
 )
 end
 links[#links+1]='#'..tostring(imageData.id)
 linksRow
 :tag('td')
 :css('text-align','right')
 :css('border','none')
 :wikitext(table.concat(links,' – '))
 end

 returntostring(root)
 end

 localfunctionrenderWarnings(args,title)
 if#warnings<1then
 returnnil
 end

 -- Error list
 localroot=mw.html.create('div')
 :css('width','468px')
 ifargs.floatthen
 root
 :css('float',args.float)
 :css('clear','both')
 else
 root:css('margin','0 auto')
 end
 locallist=root:tag('ul')
 :addClass('error')
 :css('font-size','90%')
 for_,msginipairs(warnings)do
 list
 :tag('li')
 :wikitext(string.format(
 'Wikipedia ads error: %s ([[Template:Wikipedia ads#Errors|help]]).',
 msg
 ))
 end

 -- Category. We use [[Module:Category handler]] for its blacklist.
 localmCatHandler=require('Module:Category handler')
 localcategory=mCatHandler._main{
 all='[[Category:Wikipedia ads templates with errors]]',
 nocat=args.nocat,
 page=titleandtitle.prefixedText
 }

 localret=tostring(root)
 ifcategorythen
 ret=ret..category
 end
 returnret
 end

 functionp._main(args,title)
 title=titleormw.title.getCurrentTitle()
 localret={}
 localimageData,isRandom=getImageData(args)
 ifimageDatathen
 ret[#ret+1]=renderAd(imageData,args,title,isRandom)
 end
 ret[#ret+1]=renderWarnings(args,title)
 if#ret>0then
 returntable.concat(ret)
 else
 returnnil
 end
 end

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

 returnp