Module:Class mask

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 (args[grade] 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 = args[1]
 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 args[grade]~='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 args[grade]~='no' then
      out = grade:upper()
     end
    elseif args[grade:upper()] then -- Upper-case syntax
     out = args[grade:upper()]
    elseif args[grade: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'
  args[1] = 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