-- determine whether we're being called from a sandbox
local isSandbox = mw.getCurrentFrame():getTitle():find('sandbox', 1, true)
local sandbox = isSandbox and '/sandbox' or ''

local getArgs = require('Module:Arguments').getArgs
local yesno = require('Module:Yesno')
local portalModule = require('Module:Portal'..sandbox)
local getImageName = portalModule._image
local checkPortals = portalModule._checkPortals
local processPortalArgs = portalModule._processPortalArgs

local p = {}

-- Function to format error message and tracking category
-- Arguments:
--   errMsg: string, or nil/false if no error
--   trackingCat: string for tracking category (or empty string)
local function formatError(errMsg, trackingCat)
	local result = trackingCat or ''
	if errMsg then
		local errTag = mw.html.create('span')
		errTag:addClass("error")
		errTag:css("font-size",'100%')
		errTag:wikitext("Error: "..errMsg)
		result = tostring(errTag)..result
	end
	return result
end

local function image(portal, args)
	local size = args.size == "tiny" and "16x16px" or "32x28px"
	return string.format('[[File:%s|class=noviewer|%s]]',getImageName(portal,true), size)
end

local function link(portal, args)
	local displayName = ""
	if not (args.text == "" or args.text == nil) then
		displayName = args.text
	elseif args.short then
		displayName = portal
	else
		displayName = portal .. " portal"
	end
	return string.format('[[Portal:%s|%s]]',portal,displayName)
end

function p._main(portals, args)
	mw.logObject(args)
	
	-- Normalize all arguments
	if args.redlinks == 'include' then args.redlinks = true end
	for key, default in pairs({tracking=true,redlinks=false,short=false}) do
		if args[key] == nil then args[key] = default end
		args[key] = yesno(args[key], default)
	end
	
	local trackingCat = ''
	local errMsg = nil
	
	-- Check for existing categories, drop if not. 
	-- Possible generate tracking category & error message if needed
	args.minPortals = args.minPortals or 1
	args.maxPortals = args.maxPortals or 1
	portals, trackingCat, errMsg = checkPortals(portals,args)
	-- use more specific tracking cat for inline portal
	trackingCat = mw.ustring.gsub(trackingCat,"Portal templates","Portal-inline template")
	-- either too many/few portals, or no portals left after filtering, then return
	if errMsg or #portals == 0 then
		return formatError(errMsg, trackingCat)
	end
	return image(portals[1],args)..' '..link(portals[1],args)..(trackingCat or '')
end

function p.main(frame)
	local origArgs = getArgs(frame)
	local portals, args = processPortalArgs(origArgs)
	return p._main(portals, args)
end

return p