Editing Module:Documentation

-- This module implements {{documentation}}.

-- Get required modules.
local getArgs = require('Module:Arguments').getArgs
local htmlBuilder = require('Module:HtmlBuilder')
local messageBox = require('Module:Message box')

-- Get the config table.
local cfg = mw.loadData('Module:Documentation/config')

local p = {}

-- Often-used functions.
local gsub = mw.ustring.gsub

----------------------------------------------------------------------------
-- Helper functions
----------------------------------------------------------------------------

local function message(cfgKey, expectType, valArray)
	--[[
	-- Gets a message from the cfg table and formats it if appropriate.
	-- The function raises an error if the value from the cfg table is not
	-- of the type expectType.
	-- If the table valArray is present, strings such as $1, $2 etc. in the
	-- message are substituted with values from the table keys [1], [2] etc.
	-- For example, if the message cfg.fooMessage had the value 'Foo $2 bar $1.',
	-- message('fooMessage', 'string', {'baz', 'qux'}) would return "Foo qux bar baz."
	--]]
	local msg = cfg[cfgKey]
	if expectType and type(msg) ~= expectType then
		error('message: type error in message cfg.' .. cfgKey .. ' (' .. expectType .. ' expected, got ' .. type(msg) .. ')', 2)
	end
	if not valArray then
		return msg
	end

	local function getMessageVal(match)
		match = tonumber(match)
		return valArray[match] or error('message: no value found for key $' .. match .. ' in message cfg.' .. cfgKey, 4)
	end

	local ret = gsub(msg, '$([1-9][0-9]*)', getMessageVal)
	return ret
end

local function makeWikilink(page, display)
	if display then
		return mw.ustring.format('[[%s|%s]]', page, display)
	else
		return mw.ustring.format('[[%s]]', page)
	end
end

local function makeCategoryLink(cat, sort)
	local catns = mw.site.namespaces[14].name
	return makeWikilink(catns .. '/' .. cat, sort)
end

local function makeUrlLink(url, display)
	return mw.ustring.format('[%s %s]', url, display)
end

local function makeToolbar(...)
	local ret = {}
	local lim = select('#', ...)
	if lim < 1 then
		return nil
	end
	for i = 1, lim do
		ret[#ret + 1] = select(i, ...)
	end
	return '<small style="font-style: normal;">(' .. table.concat(ret, ' &#124; ') .. ')</small>'
end	

local function err(msg)
	return string.format(
		'<strong class="error">[[Module:Documentation]] error: %s</strong>%s',
		msg,
		makeCategoryLink('Documentation template invocations with errors')
	)
end

----------------------------------------------------------------------------
-- Argument processing
----------------------------------------------------------------------------

local function makeInvokeFunc(funcName)
	return function (frame)
		local headingArg = message('headingArg', 'string')
		local args = getArgs(frame, {
			valueFunc = function (key, value)
				if type(value) == 'string' then
					value = value:match('^%s*(.-)%s*$') -- Remove whitespace.
					if key == headingArg or value ~= '' then
						return value
					else
						return nil
					end
				else
					return value
				end
			end
		})
		return p[funcName](args)
	end
end

----------------------------------------------------------------------------
-- Main function
----------------------------------------------------------------------------

p.main = makeInvokeFunc('_main')

function p._main(args)
	local env = p.getEnvironment(args)
	local root = htmlBuilder.create()
	root
		.wikitext(p.protectionTemplate(env))
		.wikitext(p.sandboxNotice(args, env))
		 -- This div tag is from {{documentation/start box}}, but moving it here
		 -- so that we don't have to worry about unclosed tags.
		.tag('div')
			.attr('id', message('mainDivId', 'string'))
			.addClass(message('mainDivClasses', 'string'))
			.newline()
			.wikitext(p._startBox(args, env))
			.wikitext(p._content(args, env))
			.tag('div')
				.css('clear', 'both') -- So right or left floating items don't stick out of the doc box.
				.newline()
				.done()
			.done()
		.wikitext(p._endBox(args, env))
		.newline()
		.wikitext(p.addTrackingCategories(env))
	return tostring(root)
end

----------------------------------------------------------------------------
-- Environment settings
----------------------------------------------------------------------------

function p.getEnvironment(args)
	-- Returns a table with information about the environment, including the title to use, the subject namespace, etc.
	-- This is called from p._main using pcall in case we get any errors from exceeding the expensive function count
	-- limit, or other perils unknown.
	--
	-- Data includes:
	-- env.title - the title object of the page we are making documentation for (usually the current title)
	-- env.subjectSpace - the number of the title's subject namespace.
	-- env.docspace - the name of the namespace the title puts its documentation in.
	-- env.templatePage - the name of the template page with no namespace or interwiki prefixes.
	local env, envFuncs = {}, {}

	-- Set up the metatable. If a nil value is called, we call that function in the envFuncs table and memoize it
	-- in the env table so we don't have to call any of the functions more than once.
	setmetatable(env, {
		__index = function (t, key)
			local envFunc = envFuncs[key]
			if envFunc then
				local val = envFunc()
				env[key] = val
				return val
			else
				return nil
			end
		end
	})	

	-- Get the title.
	function envFuncs.title()
		local title
		local titleArg = args[message('titleArg', 'string')]
		if titleArg then
			title = mw.title.new(titleArg)
			if not title then
				error(message('titleArgError', 'string', {titleArg}))
			end
		else
			title = mw.title.getCurrentTitle()
		end
		return title
	end

	-- Get the subject namespace number.
	function envFuncs.subjectSpace()
		return mw.site.namespaces[env.title.namespace].subject.id
	end
	
	-- Get the name of the documentation namespace.
	function envFuncs.docspace()
		local subjectSpace = env.subjectSpace
		if subjectSpace == 0 or subjectSpace == 6 or subjectSpace == 8 or subjectSpace == 14 then
			-- Pages in the Article, File, MediaWiki or Category namespaces must have their
			-- /doc, /sandbox and /testcases pages in talk space.
			return mw.site.namespaces[subjectSpace].talk.name 
		else
			return env.title.subjectNsText
		end
	end
	
	-- Get the template page with no namespace or interwiki prefixes.
	function envFuncs.templatePage()
		local title = env.title
		local subpage = title.subpageText
		if subpage == message('sandboxSubpage', 'string') or subpage == message('testcasesSubpage', 'string') then
			return title.baseText
		else
			return title.text
		end
	end

	function env:grab(key)
		local success, val = pcall(function() return self[key] end)
		return success, val
	end

	return env
end	

----------------------------------------------------------------------------
-- Auxiliary templates
----------------------------------------------------------------------------

function p.sandboxNotice(args, env)
	local sandboxNoticeTemplate = message('sandboxNoticeTemplate', 'string')
	if not (sandboxNoticeTemplate and env.title.subpageText == message('sandboxSubpage', 'string')) then
		return nil
	end
	local frame = mw.getCurrentFrame()
	local notice = htmlBuilder.create()
	notice
		.tag('div')
			.css('clear', 'both')
			.done()
		.wikitext(frame:expandTemplate{title = sandboxNoticeTemplate, args = {[message('sandboxNoticeLivepageParam')] = args[message('livepageArg', 'string')]}})
	return tostring(notice)
end

function p.protectionTemplate(env)
	local title = env.title
	local protectionTemplate = message('protectionTemplate', 'string')
	if not (protectionTemplate and title.namespace == 10) then
		-- Don't display the protection template if we are not in the template namespace.
		return nil
	end
	local frame = mw.getCurrentFrame()
	local function getProtectionLevel(protectionType, page)
		-- Gets the protection level for page, or for the current page if page is not specified.
		local level = frame:callParserFunction('PROTECTIONLEVEL', protectionType, page)
		if level ~= '' then
			return level
		else
			return nil -- The parser function returns the blank string if there is no match.
		end
	end
	local prefixedTitle = title.prefixedText
	if getProtectionLevel('move', prefixedTitle) == 'sysop' or getProtectionLevel('edit', prefixedTitle) then
		-- The page is full-move protected, or full, template, or semi-protected.
		return frame:expandTemplate{title = protectionTemplate, args = message('protectionTemplateArgs', 'table')}
	end
	return nil
end

----------------------------------------------------------------------------
-- Start box
----------------------------------------------------------------------------

p.startBox = makeInvokeFunc('_startBox')

function p._startBox(args, env)
	local title = env.title

	-- Arg processing from {{documentation}}.
	local preload = args[message('preloadArg', 'string')] -- Allow custom preloads.
	local heading = args[message('headingArg', 'string')] -- Blank values are not removed.
	local headingStyle = args[message('headingStyleArg', 'string')]
	local content = args[message('contentArg', 'string')]
	local docspace = env.docspace
	local docname = args[1] -- Other docname, if fed.
	local templatePage = env.templatePage

	-- Arg processing from {{documentation/start box2}}.
	local docpage
	if docname then
		docpage = docname
	else
		local namespace = docspace or title.nsText
		local pagename = templatePage or title.text
		docpage = namespace .. ':' .. pagename .. '/' .. message('docSubpage', 'string')
	end
	local docTitle = mw.title.new(docpage)
	local docExist = docTitle.exists
	
	-- Output from {{documentation/start box}}.

	-- First, check the heading parameter.
	if heading == '' then
		-- Heading is defined but blank, so do nothing.
		return nil
	end

	-- Build the start box div.
	local sbox = htmlBuilder.create('div')
	sbox
		.css('padding-bottom', '3px')
		.css('border-bottom', '1px solid #aaa')
		.css('margin-bottom', '1ex')
		.newline()

	-- Make the heading.
	local hspan = sbox.tag('span')
	if headingStyle then
		hspan.cssText(headingStyle)
	elseif subjectSpace == 10 then
		-- We are in the template or template talk namespaces.
		hspan
			.css('font-weight', 'bold')
			.css('fond-size', '125%')
	else
		hspan.css('font-size', '150%')
	end
	if heading then
		-- "heading" has data.
		hspan.wikitext(heading)
	elseif subjectSpace == 10 then -- Template namespace
		hspan.wikitext(message('documentationIconWikitext', 'string') .. ' ' .. message('templateNamespaceHeading', 'string'))
	elseif subjectSpace == 828 then -- Module namespace
		hspan.wikitext(message('documentationIconWikitext', 'string') .. ' ' .. message('moduleNamespaceHeading', 'string'))
	elseif subjectSpace == 6 then -- File namespace
		hspan.wikitext(message('fileNamespaceHeading', 'string'))
	else
		hspan.wikitext(message('otherNamespacesHeading', 'string'))
	end

	-- Add the [view][edit][history][purge] or [create] links.
	-- Check for the content parameter first, as we don't need the links if the documentation
	-- content is being entered directly onto the template page.
	if not content then
		local lspan = sbox.tag('span') -- lspan is short for "link span".
		lspan
			.addClass(message('startBoxLinkclasses', 'string'))
			.attr('id', message('startBoxLinkId', 'string'))
		if docExist then
			local viewLink = makeWikilink(docpage, message('viewLinkDisplay', 'string'))
			local editLink = makeUrlLink(docTitle:fullUrl{action = 'edit'}, message('editLinkDisplay', 'string'))
			local historyLink = makeUrlLink(docTitle:fullUrl{action = 'history'}, message('historyLinkDisplay', 'string'))
			local purgeLink = makeUrlLink(title:fullUrl{action = 'purge'}, message('purgeLinkDisplay', 'string'))
			local text = '[%s] [%s] [%s] [%s]'
			text = text:gsub('%[', '&#91;') -- Replace square brackets with HTML entities.
			text = text:gsub('%]', '&#93;')
			lspan.wikitext(mw.ustring.format(text, viewLink, editLink, historyLink, purgeLink))
		else
			if not preload then
				if subjectSpace == 6 then -- File namespace
					preload = message('fileDocpagePreload', 'string')
				else
					preload = message('docpagePreload', 'string')
				end
			end
			lspan.wikitext(makeUrlLink(docTitle:fullUrl{action = 'edit', preload = preload}, message('createLinkDisplay', 'string')))
		end
	end

	return tostring(sbox)
end

----------------------------------------------------------------------------
-- Documentation content
----------------------------------------------------------------------------

p.content = makeInvokeFunc('_content')

function p._content(args, env)
	local content = args[message('contentArg', 'string')]
	if not content then
		local docpage = args[1]
		if docpage and mw.title.new(docpage).exists then
			local frame = mw.getCurrentFrame()
			content = frame:preprocess('{{ ' .. docpage .. ' }}')
		else
			docpage = env.docspace .. ':' .. env.templatePage .. '/' .. message('docSubpage', 'string')
			if mw.title.new(docpage).exists then
				local frame = mw.getCurrentFrame()
				content = frame:preprocess('{{ ' .. docpage .. ' }}')
			end
		end
	end
	-- The line breaks below are necessary so that "=== Headings ===" at the start and end
	-- of docs are interpreted correctly.
	return '\n' .. (content or '') .. '\n' 
end

----------------------------------------------------------------------------
-- End box
----------------------------------------------------------------------------

p.endBox = makeInvokeFunc('_endBox')

function p._endBox(args, env)
	local title = env.title
	local subjectSpace = env.subjectSpace

	-- Argument processing in {{documentation}}.
	local content = args[message('contentArg', 'string')]
	local linkBox = args[message('linkBoxArg', 'string')] -- So "link box=off" works.
	local docspace = env.docspace
	local docname = args[1] -- Other docname, if fed.
	local templatePage = env.templatePage

	-- Argument processing in {{documentation/end box2}}.
	local docpageRoot = (docspace or title.nsText) .. ':' .. (templatePage or title.text)
	local docpage
	if docname then
		docpage = docname
	else
		docpage = docpageRoot .. '/' .. message('docSubpage', 'string')
	end
	local docTitle = mw.title.new(docpage)
	local docExist = docTitle.exists
	local docnameFed = args[1] and true
	local sandbox = docpageRoot .. '/' .. message('sandboxSubpage', 'string')
	local testcases = docpageRoot .. '/' .. message('testcasesSubpage', 'string')
	templatePage = title.nsText .. ':' .. templatePage

	-- Output from {{documentation/end box}}
	
	-- First, check whether we should output the end box at all. Add the end box by default if the documentation
	-- exists or if we are in the user, module or template namespaces.
	if linkBox == message('linkBoxOff', 'string') or not (docExist or subjectSpace == 2 or subjectSpace == 828 or subjectSpace == 10) then
		return nil
	end

	-- Assemble the arguments for {{fmbox}}.
	local fmargs = {}
	fmargs[message('fmboxIdParam', 'string')] = message('fmboxId', 'string') -- Sets fmargs.id = 'documentation-meta-data'
	fmargs[message('fmboxImageParam', 'string')] = message('fmboxImageNone', 'string') -- Sets fmargs.image = 'none'
	fmargs[message('fmboxStyleParam', 'string')] = message('fmboxStyle', 'string') -- Sets fmargs.style = 'background-color: #ecfcf4'
	fmargs[message('fmboxTextstyleParam', 'string')] = message('fmboxTextstyle', 'string') -- Sets fmargs.textstyle = 'font-style: italic;'

	-- Assemble the fmbox text field.
	local text = ''
	if linkBox then
		-- Use custom link box content if it is defined.
		text = text .. linkBox
	else
		if docExist then
			-- /doc exists; link to it.
			local docLink = makeWikilink(docpage)
			local editLink = makeUrlLink(docTitle:fullUrl{action = 'edit'}, message('editLinkDisplay', 'string'))
			local historyLink = makeUrlLink(docTitle:fullUrl{action = 'history'}, message('historyLinkDisplay', 'string'))
			text = text .. message('transcludedFromBlurb', 'string', {docLink}) .. ' ' .. makeToolbar(editLink, historyLink) .. '<br />'
		elseif subjectSpace == 828 then
			-- /doc does not exist; ask to create it.
			local createLink = makeUrlLink(docTitle:fullUrl{action = 'edit', preload = message('modulePreload', 'string')}, message('createLinkDisplay', 'string'))
			text = text .. message('createModuleDocBlurb', 'string', {createLink}) .. '<br />'
		end
		-- Add links to /sandbox and /testcases when appropriate.
		if subjectSpace == 2 or subjectSpace == 828 or subjectSpace == 10 then
			-- We are in the user, module or template namespaces. 
			local sandboxLinks, testcasesLinks
			local pagePossessive = subjectSpace == 828 and message('modulePossessive', 'string') or message('templatePossessive', 'string')
			local sandboxTitle = mw.title.new(sandbox)
			if sandboxTitle.exists then
				local sandboxLink = makeWikilink(sandbox, message('sandboxLinkDisplay', 'string'))
				local sandboxEditLink = makeUrlLink(sandboxTitle:fullUrl{action = 'edit'}, message('sandboxEditLinkDisplay', 'string'))
				local compareLink = makeUrlLink(mw.title.new('Special:ComparePages'):fullUrl{page1 = templatePage, page2 = sandbox}, message('compareLinkDisplay', 'string'))
				sandboxLinks = sandboxLink .. ' ' .. makeToolbar(sandboxEditLink, compareLink)
			else
				local sandboxPreload = subjectSpace == 828 and message('moduleSandboxPreload', 'string') or message('templateSandboxPreload', 'string')
				local sandboxCreateLink = makeUrlLink(sandboxTitle:fullUrl{action = 'edit', preload = sandboxPreload}, message('sandboxCreateLinkDisplay', 'string'))
				local mirrorSummary = message('mirrorEditSummary', 'string', {makeWikilink(templatePage)})
				local mirrorLink = makeUrlLink(sandboxTitle:fullUrl{action = 'edit', preload = templatePage, summary = mirrorSummary}, message('mirrorLinkDisplay', 'string'))
				sandboxLinks = message('sandboxLinkDisplay', 'string') .. ' ' .. makeToolbar(sandboxCreateLink, mirrorLink)
			end
			local testcaseTitle = mw.title.new(testcases)
			if testcaseTitle.exists then
				local testcasesLink = makeWikilink(testcases, message('testcasesLinkDisplay', 'string'))
				local testcasesEditLink = makeUrlLink(testcaseTitle:fullUrl{action = 'edit'}, message('testcasesEditLinkDisplay', 'string'))
				testcasesLinks = testcasesLink .. ' ' .. makeToolbar(testcasesEditLink)
			else
				local testcasesPreload = subjectSpace == 828 and message('moduleTestcasesPreload', 'string') or message('templateTestcasesPreload', 'string')
				local testcasesCreateLink = makeUrlLink(testcaseTitle:fullUrl{action = 'edit', preload = testcasesPreload}, message('testcasesCreateLinkDisplay', 'string'))
				testcasesLinks = message('testcasesLinkDisplay', 'string') .. ' ' .. makeToolbar(testcasesCreateLink)
			end
			text = text .. message('experimentBlurb', 'string', {pagePossessive, sandboxLinks, testcasesLinks}) .. '<br />'
			-- Show the categories text, but not if "content" fed or "docname fed" since then it is unclear where to add the categories.
			if not content and not docnameFed then
				local docPathLink = makeWikilink(docpage, message('docLinkDisplay', 'string'))
				text = text .. message('addCategoriesBlurb', 'string', {docPathLink})
			end
			-- Show the "subpages" link.
			if subjectSpace ~= 6 then -- Don't show the link in file space.
				local pagetype
				if subjectSpace == 10 then
					pagetype = message('templatePagetype', 'string')
				elseif subjectSpace == 828 then
					pagetype = message('modulePagetype', 'string')
				else
					pagetype = message('defaultPagetype', 'string')
				end
				text = text .. ' ' .. makeWikilink('Special:PrefixIndex/' .. templatePage .. '/', message('subpagesLinkDisplay', 'string', {pagetype}))
			end
			-- Show the "print" link if it exists.
			local printPage = templatePage .. '/' .. message('printSubpage', 'string')
			local printTitle = mw.title.new(printPage)
			if printTitle.exists then
				local printLink = makeWikilink(printPage, message('printLinkDisplay', 'string'))
				text = text .. '<br />' .. message('printBlurb', 'string', {printLink})
					.. (message('displayPrintCategory', 'boolean') and makeCategoryLink(message('printCategory', 'string')) or '')
			end
		end
	end
	fmargs.text = text

	-- Return the fmbox output.
	return messageBox.main('fmbox', fmargs)
end

----------------------------------------------------------------------------
-- Tracking categories
----------------------------------------------------------------------------

function p.addTrackingCategories(env)
	-- Check if {{documentation}} is transcluded on a /doc or /testcases page.
	local title = env.title
	local ret = ''
	local subpage = title.subpageText
	if message('displayStrangeUsageCategory', 'boolean') and (subpage == message('docSubpage', 'string') or subpage == message('testcasesSubpage', 'string')) then
		local sort = (title.namespace == 0 and message('strangeUsageCategoryMainspaceSort', 'string') or '') .. title.prefixedText -- Sort on namespace.
		ret = ret .. makeCategoryLink(message('strangeUsageCategory', 'string'), sort)
	end
	return ret
end

return p