Module:Class mask

local p = {}

local readarticleclass = function() -- look for article_class in page content
	local get_parameter_value = require("Module:Template parameter value").getValue
	local WPBSredirects = {'WikiProject banner shell','WikiProject banner shell/sandbox','Bannershell','Multiple wikiprojects','Project shell','Scope shell','WPB','WPBS','WPBannerShell','WP Banner Shell','WP banner shell','WikiProjectBannerShell','WikiProjectBanner Shell','WikiProjectBanners','WikiProject BannerShell','WikiProject Banner Shell','WikiProject Banners','WikiProject Banners Shell','WikiProject Shell','WikiProject banner','WikiProject banner shell/redirect','WikiProject shell','WikiprojectBannerShell','Wikiproject banner holder','Wikiproject banner shell','Wikiprojectbanners','Wikiprojectbannershell','Wpb','Wpbannershell','Wpbsgclass'}
	local target = mw.title.getCurrentTitle().prefixedText
	local success, result = get_parameter_value(target, WPBSredirects, "class", {ignoreSubtemplates=true})
	return success and result
end

local isarticle = function(class)
	local nonarticleclasses = {'Template', 'File', 'Category', 'Disambig', 'Redirect', 'Portal', 'Project', 'Draft', 'Book', 'FM'} -- these classes will not be identified as conflicting with NA-class
	local article = true
	for _,v in ipairs(nonarticleclasses) do
		if class==v then -- class matches one of the non-article classes
			article = false
			break
		end
	end
	return article
end

local ucfirst = function(s)
	-- Returns the given string with the first character in upper case.
	-- Should not be used with non-ascii strings.
	return s:sub(1, 1):upper() .. s:sub(2, -1)
end

local isTruthyBParam = function(s)
	s = s and s:lower()
	return not s or s == 'yes' or s == 'y' or s == '1' or s == 'pass' or s == 'na' or s == 'n/a' or s == '¬' or s == 'unused'
end

local resolveFQSgrade = function(grade, args)
	if (args[grade] or args.FQS) == 'yes' then
		return ucfirst(grade)
	else
		return 'NA'
	end
end

local resolveExtraGrade = function(grade, args)
	if args[grade] == 'yes' then
		return ucfirst(grade)
	else
		return 'NA'
	end
end

local resolveDefaultGrade = function(args, title, talkDefault)
	if args.ignorenamespace then
		return nil
	end
	if title.subjectPageTitle.isRedirect then
		return resolveExtraGrade('redirect',args)
	end
	local ns = title.namespace
	if ns==1 then -- Talk
		if require('Module:Disambiguation').isDisambiguation(title.subjectPageTitle:getContent()) then
			return resolveFQSgrade('disambig',args)
		else
			return talkDefault
		end
	elseif ns==7 or ns==711 then -- File talk
		return resolveFQSgrade('file', args)
	elseif ns==15 then -- Category talk
		return resolveFQSgrade('category', args)
	elseif ns==101 then -- Portal talk
		return resolveFQSgrade('portal', args)
	elseif ns==11 or ns==829 then -- Template talk
		return resolveFQSgrade('template', args)
	elseif ns==5 then -- Wikipedia talk
		return resolveFQSgrade('project', args)
	elseif ns==119 then -- Draft talk
		return resolveFQSgrade('draft', args)
	elseif ns==13 then -- Help talk
		return resolveExtraGrade('help', args)
	else
		return 'NA'
	end
end

local getGrade = function(args, title)
	local grade = args[1]
	grade = grade and grade:match('^%s*(.-)%s*$'):lower()
	local ret

	if not grade or grade == '¬' then -- undefined
		ret = '¬'

	-- Ucfirst
	elseif grade == 'start' or grade == 'stub' or grade == 'list' then
		if args[grade] ~= 'no' then
			ret = ucfirst(grade)
		end

	-- B
	elseif grade == 'b' then
		local bParams = {'b1', 'b2', 'b3', 'b4', 'b5', 'b6'}
		local isExtended = false
		for _, param in ipairs(bParams) do
			if args[param] then
				isExtended = true
				break
			end
		end
		if isExtended then
			local isB = true
			for _, param in ipairs(bParams) do
				if not isTruthyBParam(args[param]) then
					isB = false
					break
				end
			end
			ret = isB and 'B' or 'C'
		elseif args.b ~= 'no' then
			ret = 'B'
		end

	-- Upper-case
	elseif grade == 'fa' or grade == 'fl' or grade == 'a' or grade == 'ga' or grade == 'c' then
		if args[grade] ~= 'no' then
			ret = grade:upper()
		end
	elseif grade == 'na' then
		if args.forceNA == 'yes' then
			ret = resolveDefaultGrade(args, title, 'NA')
		else
			ret = 'NA'
		end
	elseif grade == 'file' or grade == 'image' or grade == 'img' then
		ret = resolveFQSgrade('file', args)
	elseif grade == 'category' or grade == 'cat' or grade == 'categ' then
		ret = resolveFQSgrade('category', args)
	elseif grade == 'dab' or grade == 'disambig' or grade == 'disambiguation' or grade == 'disamb' then
		ret = resolveFQSgrade('disambig', args)
	elseif grade == 'redirect' or grade == 'red' or grade == 'redir' then
		ret = resolveExtraGrade('redirect', args)
	elseif grade == 'help' then
		ret = resolveExtraGrade('help', args)
	elseif grade == 'portal' or grade == 'project' or grade == 'draft' then
		ret = resolveFQSgrade(grade, args)
	elseif grade == 'template' or grade == 'temp' or grade == 'tpl' or grade == 'templ' then
		ret = resolveFQSgrade('template', args)
	elseif grade == 'fm' then
		if args.fm == 'yes' then
			ret = 'FM'
		else
			ret = resolveFQSgrade('file', args)
		end

	else
		-- Upper-case syntax
		ret = args[grade:upper()]

		-- Lower-case syntax
		if not ret then
			if args[grade:lower()] == 'yes' then
				ret = mw.language.getContentLanguage():ucfirst(grade:lower())
			end
		end

		-- Defaults
		if not ret then
			ret = resolveDefaultGrade(args, title)
		end
	end
	return ret
end

p._main = function(args, title)
	title = title or mw.title.getCurrentTitle()
	local out = ''
	if title.namespace == 10 and title.subpageText == 'class' then
		out = mw.getCurrentFrame():expandTemplate{title = 'Class mask/doc warning'}
	end
	out = out .. (getGrade(args, title) or '')
	return out
end

p.main = function(frame)
	local getArgs = require('Module:Arguments').getArgs
	local args = getArgs(frame,{removeBlanks=false, wrappers='Template:Class mask'})
	return p._main(args)
end

local getclass = function(args)
	local class = '¬'
	if args.QUALITY_SCALE == 'inline' then
		class = args.class
	elseif args.QUALITY_SCALE == 'subpage' then
		if mw.title.new(args.BANNER_NAME..'/class').exists then
			local frame = mw.getCurrentFrame()
			class = frame:expandTemplate{title = args.BANNER_NAME..'/class', args = args}
		end
	else
		args.FQS = (args.QUALITY_SCALE == 'extended') and 'yes' or 'no'
		args[1] = args.class
		class = p._main(args)
	end
	return class
end

p.quality = function(frame) -- used by WPBM to check global quality and compare with local parameter
	local local_class = getclass(frame.args)
	local prefix, class = 'Y', local_class
	if local_class=='¬' then
		class = '¬'
	elseif frame.args.QUALITY_CRITERIA ~= 'custom' then -- project uses standard scale and will inherit article class if needed
		local article_class = frame.args.article_class or readarticleclass() -- checks parameter for testing purposes
		article_class = article_class and p._main{article_class, ignorenamespace=frame.args.ignorenamespace} or '¬' -- normalise if not false
		if (article_class == '¬') or (article_class == '') then -- article class does not exist, display quality class in project banner as normal
		elseif (local_class == '') or (local_class == article_class) then -- article class and local class are the same, or local is not specified
			prefix = 'H' -- hide quality class in project banner
			class = article_class
		elseif (article_class == 'NA') and not isarticle(local_class) then -- article class and local class are both non-article classes
			prefix = 'H'
		else -- article class exists and differs from local class
			prefix = 'X' -- X will indicate to meta banner that classes are different, so trigger a tracking category
		end
	end
	return (frame.args.noprefix and '' or prefix) .. class
end

return p
Quality function
