--Tary123 Google Code-in 2017, Introduction to Lua in Wikipedia



--Lua task #3 - Create your own Lua module on English Wikipedia



local p = {}



function p.hello(frame)

	return "Hello, World!"

end



--Lua task #4 - Pass information to your Lua module



p.Hi = function(frame)

	strName = frame.args.name or "Jimbo"

	return "Hello from Lua to my friend " .. strName .. ".<br>"

end



--Lua task #5 - Perform calculations in Lua



function p.temperature(frame)

	cel = frame.args.celsius or 0

	fah = cel*9/5+32

	msg = cel.." degrees Celsius is "..fah.." degrees Fahrenheit."

	

	if tonumber(cel)>9 then

		msg = msg.." It is warm.<br>"

	else

		msg = msg.." It is cold.<br>"

	end

		

	return msg

end

	

--Lua task #7 - Repeating code	

	

p.times = function(frame)

	local num = tonumber( frame.args.num ) or 2

	local out = num.." times table<br>"

	for i = 1, 12 do

		out = out .. num .. " times " .. i .. " equals " .. i * num .. "<br>"

	end

	return out

end	



--Lua task #8 - Tables in Lua



p.mum = function(frame)

	local family = {"Dad", "Mum", "Uncle Stan", "Aunty Elsie", "Brian", "Harriet", "Nicole", "Drew"}

	local msg = ""

	for i = 1, #family do

		msg = msg .. "Hello " .. familyi .. "<br>"

	end	

	return msg

end



--Lua task #9 - Using MediaWiki Libraries	

	

p.langnames = function( frame )

	local langs = mw.language.fetchLanguageNames()

	local langlist = ""

	local count = 0

	for key, value in pairs( langs ) do

		langlist = langlist .. key .. " - " .. value .. "<br>"

		count = count + 1

	end

	return langlist .. "<br>= " .. count .. " languages"

end	

	

p.pageinfo = function(frame)

	local ttl = frame.args.title

	local ttlobj = mw.title.new(ttl)

	local txt = ttlobj.prefixedText

	

	if ttlobj.exists then

		txt = txt.." exists and is "

	else

		txt = txt.." does not exist and is "

	end

	

	if not ttlobj.isRedirect then

		txt = txt.."not "

	end

	

	txt = txt.."a redirect.<br>"



	return txt

end	



--Lua task #10 - Update code of the "Reign" template on English Wikipedia



function p.reign(frame)

	local label = frame.args.label

	local show = frame.args.show or frame.args.link or frame.args.lk

	local r = frame.args.cap and "R" or "r"

	local wbr = frame.args"wrap" and "<wbr>&#8203;" or ""

	local text = ""

	

	if frame.args.sortable then

		text = "<span style='display:none; speak:none;'>"

		local sortdate = frame.args.sort_date or frame.args.sortdate or

		frame.args"sort-date" or 	frame.args.single or

		frame.args"pre-date" or frame.args.predate or frame.args.pre_date or 

		frame.args1 or frame.args2 or

		frame.args"post-date" or frame.args.postdate or frame.args.post_date

		sortdate = string.format("%04d", sortdate)

		text = text..sortdate.."</span>"

	end	

	

	text = text.."<span style='white-space:nowrap;'>"

	if label then text = text..label..""

	elseif show == "word" then	text = text..r.."eigned"

	elseif show == "colon" then	text = text..r.."eign:"

	elseif show == "lword" then	text = text.."[[Reign|"..r.."eigned]]"

	elseif show == "lcolon" then text = text.."[[Reign|"..r.."eign]]:"

	elseif show == "none" or show == "no" or show == "n" or show == "off" or show == "false" or show == "0" then text = text..r.."."

	elseif show == "link" or show == "yes" or show == "y" or show == "on" or show == "true" or show == "1" then text = text.."[[Reign|"..r..".]]"

	elseif show == "blank" then

	else text = text.."<abbr title='reign'>"..r.."</abbr>."

	end

	

	if show ~= "blank" then text = text.."&nbsp;" end

	

	local predate = frame.args"pre-date" or frame.args.predate or frame.args.pre_date

	if predate then

		predate = trim(predate)

		text = text..predate..",&nbsp;"..wbr

	end

	

	local start1 = frame.args1

	local finish1 = frame.args2

	if start1 or finish1 then

		start1 = start1 or "?"

		finish1 = finish1 or ""

		start1 = trim(start1)

		finish1 = trim(finish1)

		if start1 == "" then start1 = "?" end

		if string.find(start1, "%s") or string.find(finish1, "%s") then text = text..start1.."&nbsp;–&nbsp;"..finish1

		else text = text..start1.."–"..finish1

		end

	end

	

	local middate = frame.args"mid-date" or frame.args.middate or frame.args.mid_date

	if middate and start1 then

		middate = trim(middate)

		text = text..",&nbsp;"..wbr..middate

	end	

	

	local start2  = frame.args3

	local finish2 = frame.args4

	if start2 or finish2 then

		text = text..",&nbsp;"..wbr

		start2 = start2 or "?"

		finish2 = finish2 or ""

		start2 = trim(start2)

		finish2 = trim(finish2)

		if start2 == "" then start2 = "?" end

		if string.find(start2, "%s") or string.find(finish2, "%s") then text = text..start2.."&nbsp;–&nbsp;"..finish2

		else text = text..start2.."–"..finish2

		end

	end

	

	local postdate = frame.args.single or frame.args"post-date" or frame.args.postdate or frame.args.post_date

	if postdate then

		if finish1 or finish2 then text = text..",&nbsp;"..wbr end

		postdate = trim(postdate)

		text = text..postdate

	end

	

	local era = frame.args.era

	if era then text = text.."&nbsp;"..era end

	

	text = text.."</span>"

	

	return text

end	

	

function trim(s)

	return s:gsub("^%s+", ""):gsub("%s+$", "")

end	



--Lua task #11 - Create a general date-handling function

	

function p.extractdate(frame)

	local inputstr = frame.args1

	local dateformat = frame.args.dateformat or "dmy"

	local datestr

	

	-- Check for dates from 13-31 first, before 0-12

	-- Necessary so as to avoid accidentally catching a month when a date is given

	local dateno = inputstr:match("%D(3[01])%D") or inputstr:match("^(3[01])%D") or inputstr:match("%D(3[01])$") or

				inputstr:match("%D(2%d)%D") or inputstr:match("^(2%d)%D") or inputstr:match("%D(2%d)$") or

				inputstr:match("%D(1[3-9])%D") or inputstr:match("^(1[3-9])%D") or inputstr:match("%D(1[3-9])$") or

				inputstr:match("%D([01]?%d)%D") or inputstr:match("^([01]?%d)%D") or inputstr:match("%D([01]?%d)$")

	dateno = tonumber(dateno)			   

	local month

	local monthno

	

	-- Date 0 is not possible

	if (dateno or 0) == 0 then dateno = nil end

	

	local monthlist = {"January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"}

	local maxdays = {31, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31}

	

	local idx = #inputstr

	for i,mth in pairs(monthlist) do

		local mthabbr = mth:lower():sub(1,3)

		-- matches first month found in inputstr, regardless of case, but only if date is valid for that month

		if inputstr:lower():match(mthabbr) and inputstr:lower():find(mthabbr)<idx and (tonumber(dateno) or 0)<=maxdaysi then

			month = mth

			monthno = i

			idx = inputstr:lower():find(mthabbr)

		end

	end

	

	-- If the month number is used instead of month name

	if not month then

		monthno = inputstr:match("%D(0?%d)%D") or inputstr:match("^(0?%d)%D") or inputstr:match("%D(0?%d)$") or

				inputstr:match("%D(1?[0-2])%D") or inputstr:match("^(1?[0-2])%D") or inputstr:match("%D(1?[0-2])$")

		month = monthlisttonumber(monthno)]

		

		--Ambiguous date/month

		if dateno and tonumber(dateno)<=12 then

			month = nil

			monthno = nil

		end

	end	



	-- year gives priority to numbers preceding AD/BC/CE/BCE, followed by 4- or 3-digit numbers,

	-- followed by numbers from 32 to 99

	local year = inputstr:match("%d+%s-[ABC][DCE]") or inputstr:match("%d?%d%d%d") 

				or inputstr:match("[4-9]%d") or inputstr:match("3[2-9]")

	

	if (dateformat ~= "y" and (not dateno or not month)) or not year then

		return "Invalid date"

	end

	

	local yearno = year:match("%d+")

	year = year:gsub(yearno, tonumber(yearno))

	

	local eraformat = frame.args.eraformat or "CE"

	if eraformat == "AD" or eraformat == "BC" then

		year = year:gsub("CE", "AD")		-- "BCE" is never parsed by year

	elseif eraformat == "CE" or eraformat == "BCE" then

		year = year:gsub("AD", "CE"):gsub("BC", "BCE")

	else

		return "Invalid era format"

	end	

	

	if dateformat == "dmy" then

		datestr = dateno.." "..month.." "..year

	elseif dateformat == "mdy" then

		datestr = month.." "..dateno..", "..year

	elseif dateformat == "iso" then

		datestr = string.format("%04d", yearno).."-"..string.format("%02d", monthno).."-"..string.format("%02d", dateno)

	elseif dateformat == "y" then

		datestr = year

	else

		return "Invalid date format"

	end

	

	return datestr

end



return p