Module:Archive
| This Lua module is used on approximately 272,000 pages. To avoid major disruption and server load, any changes should be tested in the module's /sandbox or /testcases subpages. The tested changes can be added to this page in a single edit. Consider discussing changes on the talk page before implementing them. Transclusion count updated automatically (see documentation).  | 
| This module is subject to page protection. It is a highly visible module in use by a very large number of pages, or is substituted very frequently. Because vandalism or mistakes would affect many pages, and even trivial editing might cause substantial load on the servers, it is protected from editing. | 
| This module depends on the following other modules: | 
This module produces a banner for talk archive pages. The module detects surrounding archives automatically and creates navigational links to them, hence the name.
Usage
This module is accessed via a template, Template:Archive. See the template page for documentation.
Dependencies
This module uses a configuration module at Module:Archive/config. It also uses Module:Highest archive number, Module:Arguments, Module:Yesno, and Module:Message box.
See also
-------------------------------------------------------------------------------
--                       Automatic archive navigator
--
-- This module produces a talk archive banner, together with an automatically-
-- generated list of navigation links to other archives of the talk page in
-- question. It implements {{Archive}}.
-------------------------------------------------------------------------------
local yesno = require('Module:Yesno')
-------------------------------------------------------------------------------
-- Helper functions
-------------------------------------------------------------------------------
local function makeWikilink(page, display)
	if display then
		return string.format('[[%s|%s]]', page, display)
	else
		return string.format('[[%s]]', page)
	end
end
local function escapePattern(s)
	-- Escape punctuation in a string so it can be used in a Lua pattern.
	s = s:gsub('%p', '%%%0')
	return s
end
local function makeTable(width)
	local archiveTable = mw.html.create('table')
	archiveTable
		:css({
			['max-width'] = width,
			['margin'] = '0 auto 0.5em',
			['text-align'] = 'center'
		})
		-- Set width so that the table doesn't spill out on narrower skins
		-- or when zooming in. It has to be defined multiple times because 
		-- "stretch" is experimental.
		:cssText('width:100%;width:-moz-available;width:-webkit-fill-available;width:stretch')
	return archiveTable
end
-------------------------------------------------------------------------------
-- Navigator class
-------------------------------------------------------------------------------
local Navigator = {}
Navigator.__index = Navigator
function Navigator.new(args, cfg, currentTitle)
	local obj = setmetatable({}, Navigator)
	
	-- Set inputs
	obj.args = args
	obj.cfg = cfg
	obj.currentTitle = currentTitle
	-- Archive prefix
	-- Decode HTML entities so users can enter things like "Archive " from
	-- wikitext.
	obj.archivePrefix = obj.args.prefix or obj:message('archive-prefix')
	obj.archivePrefix = mw.text.decode(obj.archivePrefix)
	-- Current archive number
	do
		local pattern = string.format(
			'^%s([1-9][0-9]*)$',
			escapePattern(obj.archivePrefix)
		)
		obj.currentArchiveNum = obj.currentTitle.subpageText:match(pattern)
		obj.currentArchiveNum = tonumber(obj.currentArchiveNum)
	end
	
	-- Highest archive number
	obj.highestArchiveNum = require('Module:Highest archive number')._main(
		 obj.currentTitle.nsText ..
		 	':' .. 
			obj.currentTitle.baseText .. 
			'/' .. 
			obj.archivePrefix
	)
	return obj
end
function Navigator:message(key, ...)
	local msg = self.cfg[key]
	if select('#', ...) > 0 then
		return mw.message.newRawMessage(msg, ...):plain()
	else
		return msg
	end
end
function Navigator:makeBlurb()
	local args = self.args
	local current = self.currentTitle
	local ret
	if args.text then
		ret = args.text
	else
		local talkPage = current.nsText .. ':'
		if args.prefix then
			talkPage = talkPage .. current.baseText
		else
			talkPage = talkPage .. current.rootText
		end
		
		local namespace = 'main'
		if current.isTalkPage == true then
			namespace = 'talk'
		end
		
		local subjectPage = current.subjectNsText .. ':' .. current.rootText
		-- Prepend colon for non-mainspace pages.
		if current.subjectNsText ~= '' then
			subjectPage = ':' .. subjectPage 
		end
		
		if args.period then
			ret = self:message('blurb-period', talkPage, makeWikilink(subjectPage),
				args.period, namespace)
		else
			ret = self:message('blurb-noperiod', talkPage, makeWikilink(subjectPage),
				'', namespace)
		end
	end
	return ret
end
function Navigator:makeMessageBox()
	local args = self.args
	local image
	if args.image then
		image = args.image
	else
		local icon = args.icon or self:message('default-icon')
		image = string.format(
			'[[File:%s|%s|alt=|link=]]',
			icon,
			self:message('image-size')
		)
	end
	-- Hardcode tmbox style on the template's page.
	-- PS: Needs to be changed if the template is renamed!
	local mainTemplatePage = ''
	if self.currentTitle.fullText == 'Template:Archive' then
		mainTemplatePage = 'talk'
	end
	
	local mbox = require('Module:Message box').main('mbox', {
		demospace = args.demospace or mainTemplatePage,
		image = image,
		imageright = args.imageright,
		style = args.style or '',
		textstyle = args.textstyle or 'text-align:center',
		text = self:makeBlurb(),
	})
	return mbox
end
function Navigator:getArchiveNums()
	-- Returns an array of the archive numbers to format.
	local noLinks = tonumber(self.args.links) or self:message('default-link-count')
	noLinks = math.floor(noLinks)
	-- If |noredlinks is "yes", true or absent, don't allow red links. If it is 
	-- 'no' or false, allow red links.
	local allowRedLinks = yesno(self.args.noredlinks) == false
	
	local current = self.currentArchiveNum
	local highest = self.highestArchiveNum
	if not current or not highest or noLinks < 1 then
		return {}
	elseif noLinks == 1 then
		return {current}
	end
	local function getNum(i, current)
		-- Gets an archive number given i, the position in the array away from
		-- the current archive, and the current archive number. The first two
		-- offsets are consecutive; the third offset is rounded up to the
		-- nearest 5; and the fourth and subsequent offsets are rounded up to
		-- the nearest 10. The offsets are calculated in such a way that archive
		-- numbers will not be duplicated.
		if -2 <= i and i <= 2 then
			return current + i
		elseif -3 <= i and i <= 3 then
			return current + 2 - (current + 2) % 5 + (i / 3) * 5
		elseif 4 <= i then
			return current + 7 - (current + 7) % 10 + (i - 3) * 10
		else
			return current + 2 - (current + 2) % 10 + (i + 3) * 10
		end
	end
	local nums = {}
	-- Archive nums lower than the current page.
	for i = -1, -math.floor((noLinks - 1) / 2), -1 do
		local num = getNum(i, current)
		if num <= 1 then
			table.insert(nums, 1, 1)
			break
		else
			table.insert(nums, 1, num)
		end
	end
	-- Current page.
	if nums[#nums] < current then
		table.insert(nums, current)
	end
	-- Higher archive nums.
	for i = 1, math.ceil((noLinks - 1) / 2) do
		local num = getNum(i, current)
		if num <= highest then
			table.insert(nums, num)
		elseif allowRedLinks and (i <= 2 or i <= 3 and num == nums[#nums] + 1) then
			-- Only insert one red link, and only if it is consecutive.
			table.insert(nums, highest + 1)
			break
		elseif nums[#nums] < highest then
			-- Insert the highest archive number if it isn't already there.
			table.insert(nums, highest)
			break
		else
			break
		end
	end
	return nums
end
function Navigator:makeArchiveLinksWikitable()
	local args = self.args
	local lang = mw.language.getContentLanguage()
	local nums = self:getArchiveNums()
	local noLinks = #nums
	
	-- Skip number processing if |prev and |next are defined.
	if args.prev or args.next then
		local archives = {}
		if args.prev then archives[#archives + 1] = mw.title.new(args.prev) end
		archives[#archives + 1] = self.currentTitle
		if args.next then archives[#archives + 1] = mw.title.new(args.next) end
		
		local table = makeTable('30em')
		for i, title in ipairs(archives) do
			if tostring(title) == self.currentTitle.prefixedText then
				table:tag("td"):wikitext(string.format(
					'<span style="font-size:115%%;">%s</span>',
					makeWikilink(title.fullText, title.subpageText)
				))
			else
				table:tag("td"):wikitext(
					makeWikilink(title.fullText, title.subpageText)
				)
			end
		end
		return tostring(table)
	end
	if noLinks < 1 then
		return ''
	end
	-- Make the table of links.
	local links = {}
	local isCompact = noLinks > 7
	local currentIndex
	for i, num in ipairs(nums) do
		local subpage = self.archivePrefix .. tostring(num)
		local display
		if isCompact then
			display = tostring(num)
		else
			display = self:message('archive-link-display', num)
		end
		local link = makeWikilink('../' .. subpage, display)
		if num == self.currentArchiveNum then
			link = string.format('<span style="font-size:115%%;">%s</span>', link)
			currentIndex = i
		end
		table.insert(links, link)
	end
	-- Add the arrows.
	-- We must do the forwards arrow first as we are adding elements to the
	-- links table. If we did the backwards arrow first the index for the
	-- current archive would be wrong.
	currentIndex = currentIndex or math.ceil(#links / 2)
	for i = currentIndex + 1, #links do
		if nums[i] - nums[i - 1] > 1 then
			table.insert(links, i, lang:getArrow('forwards'))
			break
		end
	end
	for i = currentIndex - 1, 1, -1 do
		if nums[i + 1] - nums[i] > 1 then
			table.insert(links, i + 1, lang:getArrow('backwards'))
			break
		end
	end
	-- Output the wikitable.
	local width
	if noLinks <= 3 then
		width = string.format('%dem', noLinks * 10)
	elseif noLinks <= 7 then
		width = string.format('%dem', (noLinks + 3) * 5)
	else
		width = '37em'
	end
	local table = makeTable(width)
	for i, s in ipairs(links) do
		table:tag("td"):wikitext(s)
	end
	
	return tostring(table)
end
function Navigator:__tostring()
	local args = self.args
	local boxComponents
	
	-- Is |omit filled? If not, make the whole box.
	if args.omit == nil then
		boxComponents = self:makeMessageBox() .. '\n' .. self:makeArchiveLinksWikitable()
	-- We're omitting the banner, so we should only make the links table.
	elseif args.omit == 'banner' then 
		boxComponents = self:makeArchiveLinksWikitable()
	-- We're omitting the archives, so we should only make the banner.
    elseif args.omit == 'archives' then
        boxComponents = self:makeMessageBox()
	end
	
	boxComponents = boxComponents .. ' __NONEWSECTIONLINK__ __NOEDITSECTION__ __ARCHIVEDTALK__'
	return boxComponents
end
-------------------------------------------------------------------------------
-- Exports
-------------------------------------------------------------------------------
local p = {}
function p._exportClasses()
	return {
		Navigator = Navigator
	}
end
function p._aan(args, cfg, currentTitle)
	cfg = cfg or mw.loadData('Module:Archive/config')
	currentTitle = currentTitle or mw.title.getCurrentTitle()
	local aan = Navigator.new(args, cfg, currentTitle)
	return tostring(aan)
end
function p.aan(frame)
	local args = require('Module:Arguments').getArgs(frame, {
		wrappers = 'Template:Archive',
	})
	return p._aan(args)
end
return p