local MessageBox = require("Module:Message box")

local yesno = require("Module:Yesno")



local p = {}



local function demoCheck(args)

	return yesno(args"demo"]) or yesno(args"nocat"])

end



local function showWarning(text, nocat)

	mw.addWarning(text)

	return nocat and "" or "[[Category:Pages with split article warnings]]"

end



local function delink(text)

	if text == nil then

		return nil

	end

	return string.gsub(string.gsub(require("Module:Delink")._delink{text}, "%[%[", ""), "%]%]", "")

end



local function showError(text, nocat)

	return string.format(

		"%s%s %s",

		nocat and "" or "[[Category:Pages with split article errors]] ",

		tostring(

			mw.html.create("span")

				:css("color", "red")

				:css("font-weight", "bold")

				:wikitext("Error:")

		),

		text

	)

end



local function singleText(args)

	local text = ""

	-- from1 also included in case someone filed the template improperly

	local from = delink(args"from" or args"from1"]) or mw.title.getCurrentTitle().subjectPageTitle.prefixedText

	local fromTalk = mw.title.new(from).talkPageTitle.prefixedText

	

	if args"from1" then

		text = text .. showWarning(

			"<code>from</code> is not a row-based parameter. Use <code>from</code> instead of <code>from1</code>.",

			demoCheck(args)

		)

	end

	

	-- Row-based parameters

	local to = delink(args"to" or args"to1"])

	local diff = args"diff" or args"diff1"

	local date = args"date" or args"date1"

	local from_oldid = args"from_oldid" or args"from_oldid1"

    if to == nil then

    	return showError("Target page was not specified with <code>to</code>.", demoCheck(args))

	end

	if date == nil then

		text = text .. showWarning("Split date was not specified with <code>date</code>. This may cause an error in the future.", demoCheck(args))

	end

	

	text = string.format("Material from [[%s]] was split to [[%s]]", from, to, date)

	if diff ~= nil and date ~= nil then

		if diff:match("^[0123456789/]+$") then

			text = string.format("%s on [[Special:Diff/%s|%s]]", text, diff, date)

		else

			text = string.format("%s on [%s %s]", text, diff, date)

		end

	elseif date ~= nil then

		text = string.format("%s on %s", text, date)

	end

	

	if from_oldid ~= nil then

		if from_oldid:match("^[0123456789/]+$") then

			text = string.format("%s from [[Special:Diff/%s|this version]]", text, from_oldid)

		else

			text = string.format("%s from [%s this version]", text, from_oldid)

		end

	end

	text = string.format(

		"%s. The former page's [[Special:PageHistory/%s|history]] now serves to "..

		"[[Wikipedia:Copying within Wikipedia|provide attribution]] for that content "..

		"in the latter page, and it must not be deleted so long as the latter page "..

		"exists. Please leave this template in place to link the article histories "..

		"and preserve this attribution.", 

		text, from

	)

	

	if fromTalk ~= mw.title.getCurrentTitle().prefixedText then

		 text = string.format(

		 	"%s The former page's talk page can be accessed at [[%s]].",

		 	text, fromTalk

	 	)

	end

	

	return text

end



local function row(args, i)

	local to = delink(args"to" .. i or (i == 1 and args"to" or nil))

	local toTalk = mw.title.new(delink(to)).subjectPageTitle.prefixedText

	local diff = args"diff" .. i or (i == 1 and args"diff" or nil)

	local date = args"date" .. i or (i == 1 and args"date" or nil)

	local from_oldid = args"from_oldid" .. i or (i == 1 and args"from_oldid" or nil)

	if date == nil then

		text = text .. showWarning(string.format(

			"Split date for \"%s\" (<code>to%s</code>) was not specified with <code>date</code>. This may cause an error in the future.",

			to, i

		), demoCheck(args))

	end

	

	local rowText = string.format(

		"[[%s]] ([[%s|talk]] | [[Special:PageHistory/%s|history]])",

		to, toTalk, to, date, diff

	)

	if diff ~= nil and date ~= nil then

		if diff:match("^[0123456789/]+$") then

			rowText = string.format("%s on [[Special:Diff/%s|%s]]", rowText, diff, date)

		else

			rowText = string.format("%s on [%s %s]", rowText, diff, date)

		end

	elseif date ~= nil then

		rowText = string.format("%s on %s", rowText, date)

	end

	if from_oldid ~= nil then

		if from_oldid:match("^%d+$") then

			rowText = string.format("%s from [[Special:Diff/%s|this version]]", rowText, from_oldid)

		else

			rowText = string.format("%s from [%s this version]", rowText, from_oldid)

		end

	end

	

	return mw.html.create("li"):wikitext(rowText)

end



local function multiText(args)

	local text = ""

	-- from1 also included in case someone filed the template improperly

	local from = delink(args"from" or args"from1"]) or mw.title.getCurrentTitle().subjectPageTitle.prefixedText

	local fromTalk = mw.title.new(delink(from)).talkPageTitle.prefixedText

	local collapse = tonumber(args"collapse"]) or yesno(args"collapse"])

	if args"from1" then

		text = text .. showWarning(

			"<code>from</code> is not a row-based parameter. Use <code>from</code> instead of <code>from1</code>.",

			demoCheck(args)

		)

	end

	if args"from_oldid1" then

		text = text .. showWarning(

			"<code>from_oldid</code> is not a row-based parameter. Use <code>from_oldid</code> instead of <code>from_oldid1</code>.",

			demoCheck(args)

		)

	end

	

	text = string.format(

		"Material from [[%s]] was split to other pages. The former page's "..

		"[[Special:PageHistory/%s|history]] now serves to "..

		"[[Wikipedia:Copying within Wikipedia|provide attribution]] for that content "..

		"in the latter pages, and it must not be deleted so long as the latter pages "..

		"exist. Please leave this template in place to link the article histories "..

		"and preserve this attribution.", from, from

	)

	

	local ul = mw.html.create("ul")

	local ul2

	local target = ul

	

	-- Row-based parameters

	local i = 1

	while args"to" .. i or (i == 1 and args"to"]) do

		-- Swap out ul with collapsible table if collapsible

		if collapse == true and i == 1 then

			-- Only on first run

			target = mw.html.create("table")

				:attr("class", "mw-collapsible mw-collapsed")

				:attr("style", "width:100%; background-color: #f8eaba;")

				:node(mw.html.create("tr")

					:node(mw.html.create("th")

						:wikitext("Page splits")

					)

				)

				:node(mw.html.create("td"):node(ul))

		elseif collapse == (i - 1) then

			ul2 = ul

			ul = mw.html.create("ul")

			-- Only once threshold has been reached

			target = mw.html.create("table")

				:attr("class", "mw-collapsible mw-collapsed")

				:attr("style", "width:100%; background-color: #f8eaba;")

				:node(mw.html.create("tr")

					:node(mw.html.create("th")

						:wikitext("Other page splits")

					)

				)

				:node(mw.html.create("tr")

					:node(mw.html.create("td"):node(ul))

				)

		end

		

		ul:node(row(args, i))

		i = i + 1

	end

	

	if fromTalk ~= mw.title.getCurrentTitle().prefixedText then

		 text = string.format(

		 	"%s The former page's talk page can be accessed at [[%s]].",

		 	text, fromTalk

	 	)

	end

	

	text = text .. " " .. tostring(ul2 or "") .. tostring(target)

	

	return text

end



local function bannerText(args)

	-- Checks if there are multiple rows

	local text

	if args"to2" ~= nil and ((args"to1" or args"to"]) ~= nil) then

		text = multiText(args) --.. categories(args,true)

	else

		text = singleText(args) --.. categories(args,false)

	end

	return text

end



function p.renderBanner(args)

	return MessageBox.main('tmbox', {

		name = "split-article",

		small = args"small"],

		image = '[[File:Split-arrows.svg|50px]]',

		text = bannerText(args)

	})

end



function p.main(frame)

	local getArgs = require('Module:Arguments').getArgs

	local args = getArgs(frame, {

		trim = true,

		removeBlanks = true

	})

	return p.renderBanner(args)

end



return p