local p = {}



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 resolveFQSgrade = function(grade, args)

	if (argsgrade or args.FQS)=='yes' then

		return ucfirst(grade)

	else

		return 'NA'

	end

end



p._main = function(args, title)

	title = title or mw.title.getCurrentTitle()

	local out = ''

	local grade = args1

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

		out = '¬'

	else

		local ns = title.namespace

		grade = grade:match('^%s*(.-)%s*$'):lower()

		if title.subjectPageTitle.isRedirect then

			out = resolveFQSgrade('redirect',args)

		elseif ns==1 then -- Talk

			if require('Module:Disambiguation').isDisambiguation(title.subjectPageTitle:getContent()) then

				out = resolveFQSgrade('disambig',args)

			else

				if grade=='start' or grade=='stub' then -- Ucfirst

					if argsgrade~='no' then

						out = ucfirst(grade)

					end

				elseif grade=='b' or grade=='c' or grade=='fa' or grade=='fl' or grade=='a' or grade=='ga' then -- Upper-case

					if argsgrade~='no' then

						out = grade:upper()

					end

				elseif argsgrade:upper()] then -- Upper-case syntax

					out = argsgrade:upper()]

				elseif argsgrade:lower()]=='yes' then -- Lower-case syntax

					out = mw.language.getContentLanguage():ucfirst(grade:lower())

				elseif grade=='list' or grade=='sia' or grade=='si' or grade=='sl' then-- List

					if args'list'~='no' then

						out = 'List'

					end

				elseif grade=='dab' or grade=='disambig' or grade=='disambiguation' or grade=='disamb' then

					out = resolveFQSgrade('disambig', args)

				end

			end

		elseif ns==7 or ns==711 then -- File talk

			if grade=='fm' and (args.fm or args.FQS)=='yes' then

				out = 'FM'

			else

				out = resolveFQSgrade('file', args)

			end

		elseif ns==15 then -- Category talk

			out = resolveFQSgrade('category', args)

		elseif ns==101 then -- Portal talk

			out = resolveFQSgrade('portal', args)

		elseif ns==11 or ns==829 then -- Template talk

			out = resolveFQSgrade('template', args)

		elseif ns==5 then -- Wikipedia talk

			out = resolveFQSgrade('project', args)

		elseif ns==119 then -- Draft talk

			out = resolveFQSgrade('draft', args)

		elseif ns==13 and args'help'=='yes' then -- Help talk

			out = 'Help'

		elseif ns==3 and args'user'=='yes' then -- User talk

			out = 'User'

		else

			out = 'NA'

		end

	end

	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, title)

	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'

		args1 = args.class

		class = p._main(args, title)

	end

	return class

end



p.readarticleclass = function(options, page) -- used by p._quality and Module:Banner shell

	page = page or mw.title.getCurrentTitle().prefixedText

	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 success, result = get_parameter_value(page, WPBSredirects, "class", options)

	return success and result

	-- returns FALSE if banner shell template does not exist on page

	-- returns BLANK if class parameter is not defined or is defined blank

	-- otherwise returns class parameter

end



p._quality = function(args)

	local title = args.page and mw.title.new(args.page) or mw.title.getCurrentTitle()

	local local_class = getclass(args, title)

	local prefix, class = 'Y', local_class

	if local_class=='¬' then

		class = '¬'

	elseif args.QUALITY_CRITERIA ~= 'custom' then -- project uses standard scale and will inherit article class if needed

		local article_class = p.readarticleclass({ignore_subtemplates=true},title.prefixedText)

		article_class = article_class and p._main({article_class}, title)

		if article_class then -- banner shell exists

			if article_class == '' then -- no article class defined

				if local_class == '' then -- local class also does not exist, check whether any other class parameters are defined inside the shell

					local classparam = p.readarticleclass({ignore_blank=true, only_subtemplates=true},title.prefixedText)

					if classparam == '' then -- no class parameters defined, display as globally unassessed

						prefix = 'H' -- hide quality class in project banner

					end

				end

			elseif local_class == '' or local_class == article_class then -- local class matches article class or is blank

				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

	end

	return (args.noprefix and '' or prefix) .. class

end



p.quality = function(frame) -- used by WPBM to check global quality and compare with local parameter

	return p._quality(frame.args)

end



return p