Hosta

-- Function allowing for consistent treatment of boolean-like wikitext input.
local function yesno(val, default)
	val = type(val) == 'string' and val:lower() or val
	if val == nil then
		return nil
	elseif val == true 
		or val == 'yes'
		or val == 'y'
		or val == 'true'
		or val == 't'
		or val == 'on'
		or tonumber(val) == 1
	then
		return true
	elseif val == false
		or val == 'no'
		or val == 'n'
		or val == 'false'
		or val == 'f'
		or val == 'off'
		or tonumber(val) == 0
	then
		return false
	else
		return default
	end
end

local p = {}

function p._main(args, data)
	if args.link == true then
		symbol = '\[\[New Taiwan dollar|NT$\]\]'
	else
		symbol = 'NT$'
	end
	
	local lang = mw.getContentLanguage()
	local Min = lang:formatNum(args.Min)
	local Max = '–' .. lang:formatNum(args.Max)
	local magTable = {
		['k'] = ' thousand'
		,['m'] = ' million'
		,['b'] = ' billion'
		,['t'] = ' trillion'
		,['q'] = ' quadrillion'
	}
	local mag = ' ' .. magTable[args.mag]
	local MinC = args.Min / USDTWD
	
	if MaxC then
		MaxC = '–' .. args.Max / USDTWD
	end
	
	if args.showDate == false then
		year = ''
	else
		year = ' in ' .. year
	end
	
	if args.convert == true then
		conversion = table.concat({' (US$', MinC, MaxC, magC, today, ')'})
	else
		conversion = ''
	end
	
	return table.concat({symbol, Min, Max, mag, year, conversion})
end

function p.main(frame)
	local _args = frame:getParent().args or frame.args
	local args = {
	Min = tonumber(_args[1])
	,Max = tonumber(_args[2])
	,link = yesno(_args.link) or yesno(_args.l) or true
	,mag = _args.mag or _args.m or _args.o
	,convert = yesno(_args.conv) or yesno(_args.c) or true
	,year = _args.year
	,showYear = yesno(_args.showYear) or yesno(_args.sy) or yesno(_args.sd) or false
	}
	local data = {
		['USDTWD'] = mw.loadData('Module:New Taiwan dollar/USDTWD annual')
		,['CPI'] = mw.loadData('Module:New Taiwan dollar/CPI annual')
	}
	return p._main(args, data)
end