Module:Prevnext

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

require( 'strict' )

local Prevnext = {}

local metatable = {}
local methodtable = {}


metatable.__index = methodtable


--- Returns true if a page exists
--- @param page string
--- @return boolean
local function pageExists( page )
	local title = mw.title.new( page )
	return title and title.exists
end


--- Creates the prev/next header
---
--- @return string
function methodtable.make( self )
	local function makeLink( dir )
		if not self.frameArgs[ dir ] then
			return
		end

		local arrow = 'ArrowPrevious'
		if dir == 'next' then arrow = 'ArrowNext' end

		local inner = mw.html.create( 'div' )
		inner:addClass( 'template-prevnext__' .. dir )
		   :addClass( 'template-prevnext__link' )

		if not pageExists( self.frameArgs[ dir ] ) then
			inner:addClass( 'template-prevnext__link--new' )
		end

		local icon = mw.html.create( 'div' )

		icon:addClass( 'template-prevnext__icon' )
				:wikitext( mw.ustring.format( '[[File:WikimediaUI-%s-ltr.svg|14px|link=]]', arrow ) )
			:done()

		if dir == 'prev' then
			inner:node( icon )
		end

		local content = inner:tag( 'div' )
				:addClass( 'template-prevnext__content' )
					:tag( 'div' )
						:addClass( 'template-prevnext__title' )
						:wikitext( self.frameArgs[ dir .. 'Title' ] or self.frameArgs[ dir ] )
					:done()

		if self.frameArgs[ dir .. 'Desc' ] then
			content:tag( 'div' )
					:addClass( 'template-prevnext__desc' )
						:wikitext( self.frameArgs[ dir .. 'Desc' ] )
					:done()
		end

		if dir == 'next' then
			inner:node( icon )
		end

		inner:tag( 'div' )
				:addClass( 'template-prevnext__linkoverlay' )
					:wikitext( mw.ustring.format( '[[%s]]', self.frameArgs[ dir ] ) )
				:allDone()

		return inner
	end

	local div = mw.html.create( 'div' )
		div:addClass( 'template-prevnext' )

	local current = mw.html.create( 'div' )
	current:addClass( 'template-prevnext__current' )

	local content = current:tag( 'div' )
			:addClass('template-prevnext__content')
				:tag( 'div' )
					:addClass('template-prevnext__title')
					:wikitext( self.frameArgs[ 'title' ] or mw.title.getCurrentTitle().subpageText )
				:done()

	if self.frameArgs[ 'desc' ] then
		content:tag( 'div' )
			:addClass( 'template-prevnext__desc' )
			:wikitext( self.frameArgs[ 'desc' ] )
	end

	current:allDone()

	div:node(makeLink('prev')):node(current):node(makeLink('next'))

	return tostring( div:allDone() ) .. mw.getCurrentFrame():extensionTag{
		name = 'templatestyles', args = { src = 'Module:Prevnext/styles.css' }
	}
end


--- Set the frame and load args
--- @param frame table
function methodtable.setFrame( self, frame )
	self.currentFrame = frame
	self.frameArgs = require( 'Module:Arguments' ).getArgs( frame )
end


--- New Instance
function Prevnext.new( self, args )
	local instance = {
		frameArgs = args
	}

	setmetatable( instance, metatable )

	return instance
end


--- Template entry
function Prevnext.main( frame )
	local instance = Prevnext:new()
	instance:setFrame( frame )

	return instance:make()
end


return Prevnext