-- This module implements {{portal bar}}.

require('Module:No globals')

local portalModule = require('Module:Portal')
local getImageName = portalModule.image
local checkTracking = portalModule._checkTracking
local processPortalArgs = portalModule._processPortalArgs
local yesno = require( 'Module:Yesno' )
local getArgs = require('Module:Arguments').getArgs
local p = {}

local function sandbox(args, s)
	return args.sandbox and s.."-sand" or s
end

-- Builds the portal bar used by {{portal bar}}.
function p._main( portals, args )
	
	-- Don't display a blank navbox if no portals were specified.
	if (not portals) or (#portals < 1) then return '' end
	
	-- check for sensible args
	args = type(args) == "table" and args or {}
	
	-- Normalize arguments
	for key, default in pairs({border=true,redlinks=false,sandbox=false,tracking=true}) do
		if args[key] == nil then args[key] = default end
		args[key] = yesno(args[key], default)
	end

	local nav = mw.html.create( 'div' )
		:addClass(sandbox(args,'portal-bar'))
		:addClass( 'noprint metadata noviewer' )
		:attr( 'role', 'navigation' )
		:attr( 'aria-label' , 'Portals' )
		:addClass(sandbox(args,args.border and 'portal-bar-bordered' or 'portal-bar-unbordered'))
	
	local trackingEnabled = args.tracking and checkTracking()

	-- scan for nonexistent portals, if they exist remove them from the portals
	-- table. If redlinks=yes, then don't remove
	local trackingCats = ''
	if not args.redlinks or trackingEnabled then
		local existingPortals = {}
		for _, portal in ipairs(portals) do
			local portalTitle = mw.title.new(portal,"Portal")
			if portalTitle and portalTitle.exists then
				table.insert(existingPortals,portal)
			elseif trackingEnabled then
				trackingCats = "[[Category:Portal templates with redlinked portals]]"
			end
		end
		portals = args.redlinks and portals or existingPortals
		if #portals == 0 then
			return trackingEnabled and "[[Category:Portal templates with all redlinked portals]]" or ""
		end
	end
	
	local header = nav:tag('span')
	header:addClass(sandbox(args,'portal-bar-header'))
	header:wikitext('[[Wikipedia:Contents/Portals|Portal]]')
	if #portals > 1 then
		header:wikitext('s')
	end
	header:wikitext(':')
	local container = nav:tag('div')
	container:addClass(sandbox(args,'portal-bar-content'))
	for _, portal in ipairs( portals ) do
		container
			:tag( 'div' )
			:addClass(sandbox(args,'portal-bar-item'))
				:tag( 'span' )
					:addClass(sandbox(args,'portal-bar-logo'))
					:wikitext( string.format(
						'[[File:%s|21x19px|alt=]]', getImageName{ portal }
					) )
					:done()
				:tag('span')
					:addClass(sandbox(args,'portal-bar-link'))
					:wikitext( string.format('[[Portal:%s|%s]]', portal, portal))
	end
	
	local styleFile = 'Module:Portal bar/'
	styleFile = styleFile..(args.sandbox and 'sandbox/' or '')
	styleFile = styleFile..'styles.css'
	return mw.getCurrentFrame():extensionTag{
		name = 'templatestyles', args = { src = styleFile }
	} .. tostring( nav ) .. trackingCats
end

-- Processes external arguments and sends them to the other functions.
function p.main( frame )
	local origArgs = getArgs(frame)
	local portals, args = processPortalArgs(origArgs)
	return p._main( portals, args )
end

return p