Editing Module:Statsbar

local p = {}
local args = {}
local origArgs = {}
local root

-- Returns a table containing the numbers of the arguments that exist
-- for the specified prefix. For example, if the prefix was 'data', and
-- 'data1', 'data2', and 'data5' exist, it would return {1, 2, 5}.
local function getArgNums(prefix)
	local nums = {}
	for k, v in pairs(args) do
		local num = tostring(k):match('^' .. prefix .. '([1-9]%d*)$')
		if num then table.insert(nums, tonumber(num)) end
	end
	table.sort(nums)
	return nums
end

local function addItem(itemArgs, root)
	local item = root:tag('div')
	item:addClass('template-statsbar__item')
	
	if itemArgs.label then
		item
			:tag('div')
			:addClass('template-statsbar__label')
			:wikitext(itemArgs.label)
			:done()
	end
	
	item
		:tag('div')
			:addClass('template-statsbar__data')
			:wikitext(itemArgs.data)
			:done()
			
	if itemArgs.desc then
		item
			:tag('div')
			:addClass('template-statsbar__desc')
			:wikitext(itemArgs.desc)
			:done()
	end
end

local function renderItems(root)
    -- Gets the data argument numbers,
    -- and renders them all in order using addItems.
    local itemnums = getArgNums('data')
    table.sort(itemnums)
    for k, num in ipairs(itemnums) do
        addItem({
            label = args['label' .. tostring(num)],
            data = args['data' .. tostring(num)],
            desc = args['desc' .. tostring(num)],
        },
        root)
    end
end

-- If the argument exists and isn't blank, add it to the argument table.
-- Blank arguments are treated as nil to match the behaviour of ParserFunctions.
local function preprocessSingleArg(argName)
	if origArgs[argName] and origArgs[argName] ~= '' then
		args[argName] = origArgs[argName]
	end
end

-- Assign the parameters with the given prefixes to the args table, in order, in
-- batches of the step size specified. This is to prevent references etc. from
-- appearing in the wrong order. The prefixTable should be an array containing
-- tables, each of which has two possible fields, a "prefix" string and a
-- "depend" table. The function always parses parameters containing the "prefix"
-- string, but only parses parameters in the "depend" table if the prefix
-- parameter is present and non-blank.
local function preprocessArgs(prefixTable, step)
	if type(prefixTable) ~= 'table' then
		error("Non-table value detected for the prefix table", 2)
	end
	if type(step) ~= 'number' then
		error("Invalid step value detected", 2)
	end

	-- Get arguments without a number suffix, and check for bad input.
	for i,v in ipairs(prefixTable) do
		if type(v) ~= 'table' or type(v.prefix) ~= "string" or
			(v.depend and type(v.depend) ~= 'table') then
			error('Invalid input detected to preprocessArgs prefix table', 2)
		end
		preprocessSingleArg(v.prefix)
		-- Only parse the depend parameter if the prefix parameter is present
		-- and not blank.
		if args[v.prefix] and v.depend then
			for j, dependValue in ipairs(v.depend) do
				if type(dependValue) ~= 'string' then
					error('Invalid "depend" parameter value detected in preprocessArgs')
				end
				preprocessSingleArg(dependValue)
			end
		end
	end

	-- Get arguments with number suffixes.
	local a = 1 -- Counter variable.
	local moreArgumentsExist = true
	while moreArgumentsExist == true do
		moreArgumentsExist = false
		for i = a, a + step - 1 do
			for j,v in ipairs(prefixTable) do
				local prefixArgName = v.prefix .. tostring(i)
				if origArgs[prefixArgName] then
					-- Do another loop if any arguments are found, even blank ones.
					moreArgumentsExist = true
					preprocessSingleArg(prefixArgName)
				end
				-- Process the depend table if the prefix argument is present
				-- and not blank, or we are processing "prefix1" and "prefix" is
				-- present and not blank, and if the depend table is present.
				if v.depend and (args[prefixArgName] or (i == 1 and args[v.prefix])) then
					for j,dependValue in ipairs(v.depend) do
						local dependArgName = dependValue .. tostring(i)
						preprocessSingleArg(dependArgName)
					end
				end
			end
		end
		a = a + step
	end
end

local function parseDataParameters()
	preprocessSingleArg('id')
	preprocessArgs({
		{prefix = 'label', depend = {'data'}},
		{prefix = 'desc', depend = {'data'}},
	}, 50)
end

local function _statsbar()
	root = mw.html.create('div')
	root:addClass('template-statsbar')

	renderItems(root)
		
	if args.id then root:attr('id', 'statsbar-' .. args.id) end

    return mw.getCurrentFrame():extensionTag{
		name = 'templatestyles', args = { src = 'Module:Statsbar/styles.css' }
	} .. tostring(root)
end

-- If called via #invoke, use the args passed into the invoking template.
-- Otherwise, for testing purposes, assume args are being passed directly in.
function p.statsbar(frame)
    if frame == mw.getCurrentFrame() then
		origArgs = frame:getParent().args
	else
		origArgs = frame
	end
	
	parseDataParameters()
	
	return _statsbar()
end

-- For calling via #invoke within a template
function p.statsbarTemplate(frame)
	origArgs = {}
	for k,v in pairs(frame.args) do origArgs[k] = mw.text.trim(v) end
	
	parseDataParameters()

	return _statsbar()
end
return p