Module:Portal bar

Documentation for this module may be created at Module:Portal bar/doc

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

require('Module:No globals')

local getImageName = require( 'Module:Portal' ).image
local yesno = require( 'Module:Yesno' )
local p = {}

local function checkPortalExists(portal)
	return not (mw.title.makeTitle(100, portal).id == 0)
end

-- Check whether to do tracking in this namespace
-- Returns true unless the page is one of the banned namespaces
local function isTrackedNamespace()
	local thisPageNS = mw.title.getCurrentTitle().namespace
	return thisPageNS ~= 1 -- Talk
		and thisPageNS ~= 2 -- User
		and thisPageNS ~= 3 -- User talk
		and thisPageNS ~= 5 -- Wikipedia talk
		and thisPageNS ~= 7 -- File talk
		and thisPageNS ~= 11 -- Template talk
		and thisPageNS ~= 15 -- Category talk
		and thisPageNS ~= 101 -- Portal talk
		and thisPageNS ~= 118 -- Draft
		and thisPageNS ~= 119 -- Draft talk
		and thisPageNS ~= 829 -- Module talk
end

-- Check whether to do tracking on this pagename
-- Returns false if the page title matches one of the banned strings
-- Otherwise returns true
local function isTrackedPagename()
	local thisPageLC = mw.ustring.lower(mw.title.getCurrentTitle().text)
	local match = string.match
	return match(thisPageLC, "/archive") == nil
		and match(thisPageLC, "/doc") == nil
		and match(thisPageLC, "/test") == nil
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 #portals < 1 then return '' end
	
	local nav = mw.html.create( 'ul' )
		:addClass( 'portal-bar noprint metadata' )
		:attr( 'role', 'navigation' )
		:attr( 'aria-label' , 'Portals' )
	if yesno( args.border ) == false then
		nav
			:addClass('portal-bar-unbordered')
	else
		nav
			:addClass( 'portal-bar-bordered' )
	end
	
	local trackingEnabled = true
	local tracking = args.tracking
	if (tracking == 'no' or tracking == 'n' or tracking == 'false') or
		not isTrackedNamespace() or not isTrackedPagename() then
		trackingEnabled = false
	end

	-- TODO: This used to say 'if no portals are specified', but we return early
	-- above. Someone should check whether this is really 'portals[1]' or #portals < 0.
	-- I don't believe the block in the conditional is reachable currently
	-- because if it were we would probably get a Lua script error because
	-- warning was previously undefined
	
	-- If the first portal is not specified,
	-- display an error and add the page to a tracking category.
	if not portals[1] then
		local nominimum = args.nominimum
		local warning = mw.html.create()
		if nominimum ~= 'yes' and nominimum ~= 'y' and nominimum ~= 'true' then
			warning:tag('strong')
				:addClass('error')
				:wikitext('No portals specified: please specify at least one portal')
		end
		if trackingEnabled then
			warning:wikitext('[[Category:Portal templates without a parameter]]')
		end
		return tostring(warning)
	end

	-- scan for nonexistent portals, if they exist remove them from the portals
	-- table. If redlinks=yes, then don't remove
	local portallen = #portals
	-- traverse the list backwards to ensure that no portals are missed
	-- (table.remove also moves down the portals in the list, so that the next
	-- portal isn't checked if going fowards. going backwards allows us to
	-- circumvent this issue
	for i=portallen,1,-1 do
		-- the use of pcall here catches any errors that may occour when
		-- attempting to locate pages when the page name is invalid. if pcall
		-- returns true, then rerun the function to find if the page exists
		if not pcall(checkPortalExists, portals[i]) or not checkPortalExists(portals[i]) then
			-- Getting here means a redlinked portal has been found
			local redlinks = args.redlinks
			if redlinks == 'yes' or redlinks == 'y' or redlinks == 'true' or redlinks == 'include' then
				-- if redlinks as been set to yes (or similar), add the cleanup
				-- category and then break the loop before the portal is removed
				-- from the list
				if trackingEnabled then
					nav:wikitext('[[Category:Portal templates with redlinked portals]]')
				end
				-- TODO: This looks buggy given the comment above; we will always
				-- break if redlinks are yes, whether or not tracking is enabled
				break
			end
			-- remove the portal (this does not happen if redlinks=yes)
			table.remove(portals,i)
		end
	end
	
	-- if the length of the table is different, then rows were removed from the
	-- table, so portals were removed. If this is the case add the cleanup category
	if portallen ~= #portals then
		if #portals == 0 then
        	if trackingEnabled then
				return '[[Category:Portal templates with all redlinked portals]]'
			else
				return ""
			end
        end
		if trackingEnabled then
			nav:wikitext('[[Category:Portal templates with redlinked portals]]')
		end
	end
	
	for _, portal in ipairs( portals ) do
		nav
			:tag( 'li' )
				:tag( 'span' )
					:wikitext( string.format(
						'[[File:%s|24x21px|alt=]]', getImageName{ portal }
					) )
					:done()
				:wikitext( string.format(
					'[[Portal:%s|%s portal]]', portal, portal
				) )
	end
	
	return mw.getCurrentFrame():extensionTag{
		name = 'templatestyles', args = { src = 'Module:Portal bar/styles.css' }
	} .. tostring( nav )
end

-- Processes external arguments and sends them to the other functions.
function p.main( frame )
	-- If called via #invoke, use the args passed into the invoking template, or
	-- the args passed to #invoke if any exist. Otherwise assume args are being
	-- passed directly in from the debug console or from another Lua module.
	local origArgs
	if type( frame.getParent ) == 'function' then
		origArgs = frame:getParent().args
		for k, v in pairs( frame.args ) do
			origArgs = frame.args
			break
		end
	else
		origArgs = frame
	end
	-- Process the args to make an array of portal names that can be used with
	-- ipairs. We need to use ipairs because we want to list all the portals in
	-- the order they were passed to the template, but we also want to be able
	-- to deal with positional arguments passed explicitly, for example
	-- {{portal|2=Politics}}. The behaviour of ipairs is undefined if nil values
	-- are present, so we need to make sure they are all removed.
	local portals, args = {}, {}
	for k, v in pairs( origArgs ) do
		-- Make sure we have no non-string portal names.
		if type( k ) == 'number' and type( v ) == 'string' then
			if mw.ustring.find( v, '%S' ) then -- Remove blank values.
				table.insert( portals, k )
				end
			elseif type( k ) ~= 'number' then -- Separate named arguments from portals.
			if type( v ) == 'string' then
				v = mw.text.trim( v )
			end
			args[ k ] = v
		end
	end
	table.sort( portals )
	for i, v in ipairs( portals ) do
		-- Swap keys with values, trimming whitespace.
		portals[ i ] = mw.text.trim( origArgs[ v ] )
	end
	return p._main( portals, args )
end

return p