Module:Time ago

 -- Implement [[Template:Time ago]]

 localnumberSpell,yesno-- lazy load

 functionnumberSpell(arg)
 numberSpell=require('Module:NumberSpell')._main
 returnnumberSpell(arg)
 end

 functionyesno(arg)
 yesno=require('Module:Yesno')
 returnyesno(arg)
 end

 localp={}

 -- Table to convert entered text values to numeric values.
 localtimeText={
 ['seconds']=1,
 ['minutes']=60,
 ['hours']=3600,
 ['days']=86400,
 ['weeks']=604800,
 ['months']=2629800,-- 365.25 * 24 * 60 * 60 / 12
 ['years']=31557600
 }

 -- Table containing tables of possible units to use in output.
 localtimeUnits={
 [1]={'second','seconds',"second's","seconds'"},
 [60]={'minute','minutes',"minutes'","minutes'"},
 [3600]={'hour','hours',"hour's","hours'"},
 [86400]={'day','days',"day's","days'"},
 [604800]={'week','weeks',"week's","weeks'",unit='w'},
 [2629800]={'month','months',"month's","months'",unit='m'},
 [31557600]={'year','years',"year's","years'",unit='y'}
 }

 functionp._main(args)
 -- Initialize variables
 locallang=mw.language.getContentLanguage()
 localauto_magnitude_num
 localmin_magnitude_num
 localmagnitude=args.magnitude
 localmin_magnitude=args.min_magnitude
 localpurge=args.purge

 -- Add a purge link if something (usually "yes") is entered into the purge parameter
 ifpurgethen
 purge=' <span class="plainlinks">(['..mw.title.getCurrentTitle():fullUrl('action=purge')..' purge])</span>'
 else
 purge=''
 end

 -- Check that the entered timestamp is valid. If it isn't, then give an error message.
 localsuccess,inputTime=pcall(lang.formatDate,lang,'xnU',args[1])
 ifnotsuccessthen
 return'<strong class="error">Error: first parameter cannot be parsed as a date or time.</strong>'
 end

 -- Store the difference between the current time and the inputted time, as well as its absolute value.
 localtimeDiff=lang:formatDate('xnU')-inputTime
 localabsTimeDiff=math.abs(timeDiff)

 ifmagnitudethen
 auto_magnitude_num=0
 min_magnitude_num=timeText[magnitude]
 else
 -- Calculate the appropriate unit of time if it was not specified as an argument.
 localautoMagnitudeData={
 {factor=2,amn=31557600},
 {factor=2,amn=2629800},
 {factor=2,amn=86400},
 {factor=2,amn=3600},
 {factor=2,amn=60}
 }
 for_,tinipairs(autoMagnitudeData)do
 ifabsTimeDiff/t.amn>=t.factorthen
 auto_magnitude_num=t.amn
 break
 end
 end
 auto_magnitude_num=auto_magnitude_numor1
 ifmin_magnitudethen
 min_magnitude_num=timeText[min_magnitude]
 else
 min_magnitude_num=-1
 end
 end

 ifnotmin_magnitude_numthen
 -- Default to seconds if an invalid magnitude is entered.
 min_magnitude_num=1
 end

 localresult_num
 localmagnitude_num=math.max(min_magnitude_num,auto_magnitude_num)
 localunit=timeUnits[magnitude_num].unit
 ifunitandabsTimeDiff>=864000then
 localDate=require('Module:Date')._Date
 localinput=lang:formatDate('Y-m-d H:i:s',args[1])-- Date needs a clean date
 input=Date(input)
 ifinputthen
 localid
 ifinput.hour==0andinput.minute==0then
 id='currentdate'
 else
 id='currentdatetime'
 end
 result_num=(Date(id)-input):age(unit)
 end
 end
 result_num=result_numormath.floor(absTimeDiff/magnitude_num)

 localpunctuation_key,suffix
 iftimeDiff>=0then-- Past
 ifresult_num==1then
 punctuation_key=1
 else
 punctuation_key=2
 end
 ifargs.ago==''then
 suffix=''
 else
 suffix=' '..(args.agoor'ago')
 end
 else-- Future
 ifargs.ago==''then
 suffix=''
 ifresult_num==1then
 punctuation_key=1
 else
 punctuation_key=2
 end
 else
 suffix=' time'
 ifresult_num==1then
 punctuation_key=3
 else
 punctuation_key=4
 end
 end
 end
 localresult_unit=timeUnits[magnitude_num][punctuation_key]

 -- Convert numerals to words if appropriate.
 localspell_out=args.spellout
 localspell_out_max=tonumber(args.spelloutmax)
 localresult_num_text
 ifspell_outand(
 (spell_out=='auto'and1<=result_numandresult_num<=9andresult_num<=(spell_out_maxor9))or
 (yesno(spell_out)and1<=result_numandresult_num<=100andresult_num<=(spell_out_maxor100))
 )
 then
 result_num_text=numberSpell(result_num)
 else
 result_num_text=tostring(result_num)
 end

 -- numeric or string
 localnumeric_out=args.numeric
 localresult=""
 ifnumeric_outthen
 result=tostring(result_num)
 else
 result=result_num_text..' '..result_unit..suffix-- Spaces for suffix have been added in earlier.
 end

 returnresult..purge
 end

 functionp.main(frame)
 localargs=require('Module:Arguments').getArgs(frame,{
 valueFunc=function(k,v)
 ifvthen
 v=v:match('^%s*(.-)%s*$')-- Trim whitespace.
 ifk=='ago'orv~=''then
 returnv
 end
 end
 returnnil
 end,
 wrappers='Template:Time ago'
 })
 returnp._main(args)
 end

 returnp