Editing Module:Shortcut

-- This module implements {{shortcut}}.

-- Set constants
local CONFIG_MODULE = 'Module:Shortcut/config'

-- Load required modules
local checkType = require('libraryUtil').checkType

local p = {}

function p._main(shortcuts, options, frame, cfg)
	checkType('_main', 1, shortcuts, 'table')
	checkType('_main', 2, options, 'table', true)
	options = options or {}
	frame = frame or mw.getCurrentFrame()
	cfg = cfg or mw.loadData(CONFIG_MODULE)

	-- Validate shortcuts
	for i, shortcut in ipairs(shortcuts) do
		if type(shortcut) ~= 'string' or #shortcut < 1 then
			error(string.format(
				'shortcut #%d was invalid (shortcuts must be strings of ' ..
				'at least one character in length)'
			), 2)
		end
	end

	-- Make the list items. These are the shortcuts plus any extra lines such
	-- as options.msg.
	local listItems = {}
	for i, shortcut in ipairs(shortcuts) do
		listItems[i] = string.format('[[%s]]', shortcut)
	end
	table.insert(listItems, options.msg)
	local nListItems = #listItems

	-- Exit if we have nothing to display
	if nListItems < 1 then
		return nil
	end

	local root = mw.html.create()

	-- Anchors
	local anchorDiv = root
		:tag('div')
			:css('position', 'relative')
			:css('top', '-3em')
	for i, shortcut in ipairs(shortcuts) do
		local anchor = mw.uri.anchorEncode(shortcut)
		anchorDiv:tag('span'):attr('id', anchor)
	end

	root:newline() -- To match the old [[Template:Shortcut]]

	-- Shortcut heading
	local shortcutHeading = mw.message.newRawMessage(
		cfg['shortcut-heading'],
		nListItems
	):plain()
	shortcutHeading = frame:preprocess(shortcutHeading)

	-- Shortcut box
	local shortcutList = root
		:tag('table')
			:addClass('shortcutbox noprint')
			:css('float', 'right')
			:css('border', '1px solid #aaa')
			:css('background', '#fff')
			:css('margin', '.3em .3em .3em 1em')
			:css('padding', '3px')
			:css('text-align', 'center')
				:tag('tr')
					:tag('th')
						:addClass('plainlist')
						:css('border', 'none')
						:css('background', 'transparent')
						:tag('small')
							:wikitext(shortcutHeading)
							:newline()
							:tag('ul')
	for i, item in ipairs(listItems) do
		shortcutList:tag('li'):wikitext(item)
	end

	-- Error category
	if shortcuts[1] then
		local title = mw.title.new(shortcuts[1])
		if not title or not title.exists then
			root:wikitext(string.format(
				'[[%s:%s]]',
				mw.site.namespaces[14].name,
				cfg['first-parameter-error-category']
			))
		end
	end

	return tostring(root)
end

function p.main(frame)
	local args = require('Module:Arguments').getArgs(frame, {
		wrappers = 'Template:Shortcut'
	})

	-- Separate shortcuts from options
	local shortcuts, options = {}, {}
	for k, v in pairs(args) do
		if type(k) == 'number' then
			shortcuts[k] = v
		else
			options[k] = v
		end
	end

	-- Compress the shortcut array, which may contain nils.
	local function compressArray(t)
		local nums, ret = {}, {}
		for k in pairs(t) do
			nums[#nums + 1] = k
		end
		table.sort(nums)
		for i, num in ipairs(nums) do
			ret[i] = t[num]
		end
		return ret
	end
	shortcuts = compressArray(shortcuts)

	return p._main(shortcuts, options, frame)
end

return p