require('strict')
local p = {}
local cfg = mw.loadData('Module:Navbox/configuration/sandbox')
local inArray = require("Module:TableTools").inArray
local getArgs -- lazily initialized

-- global passthrough variables
local passthrough = {
		[cfg.arg.above]=true,[cfg.arg.aboveclass]=true,[cfg.arg.abovestyle]=true,
		[cfg.arg.basestyle]=true,
		[cfg.arg.below]=true,[cfg.arg.belowclass]=true,[cfg.arg.belowstyle]=true,
		[cfg.arg.bodyclass]=true,
		[cfg.arg.groupclass]=true,
		[cfg.arg.image]=true,[cfg.arg.imageclass]=true,[cfg.arg.imagestyle]=true,
		[cfg.arg.imageleft]=true,[cfg.arg.imageleftstyle]=true,
		[cfg.arg.listclass]=true,
		[cfg.arg.name]=true,
		[cfg.arg.navbar]=true,
		[cfg.arg.state]=true,
		[cfg.arg.title]=true,[cfg.arg.titleclass]=true,[cfg.arg.titlestyle]=true,
}

-- helper functions
local andnum = function(s, n) return string.format(cfg.arg[s..'_and_num'], n) end
local isblank = function(v) return (v or '') == '' end

local function concatstrings(s)
	local r = table.concat(s, '')
	if r:match('^%s*$') then return nil end
	return r
end
	
local function concatstyles(s)
	local r = ''
	for _, v in ipairs(s) do
		v = mw.text.trim(v, "%s;")
		if not isblank(v) then r = r .. v .. ';' end
	end
	if isblank(r) then return nil end
	return r
end
	
local function getSubgroup(args, listnum, listText, prefix)
	local subArgs = {
		[cfg.arg.border] = cfg.keyword.border_subgroup,
		[cfg.arg.navbar] = cfg.keyword.navbar_plain
	}
	local hasSubArgs = false
	local subgroups = prefix and {prefix} or cfg.keyword.subgroups
	for k, v in pairs(args) do
		k = tostring(k)
		for _, w in ipairs(subgroups) do
			w = w .. listnum .. "_"
			if (#k > #w) and (k:sub(1, #w) == w) then
				subArgs[k:sub(#w + 1)] = v
				hasSubArgs = true
			end
		end
	end
	return hasSubArgs and p._navbox(subArgs) or listText
end

-- Main functions
function p._navbox(args)
	if args.type == cfg.keyword.with_collapsible_groups then
		return p._withCollapsibleGroups(args)
	elseif args.type == cfg.keyword.with_columns then
		return p._withColumns(args)
	end

	local function striped(wikitext, border)
		-- Return wikitext with markers replaced for odd/even striping.
		-- Child (subgroup) navboxes are flagged with a category that is removed
		-- by parent navboxes. The result is that the category shows all pages
		-- where a child navbox is not contained in a parent navbox.
		local orphanCat = cfg.category.orphan
		if border == cfg.keyword.border_subgroup and args[cfg.arg.orphan] ~= cfg.keyword.orphan_yes then
			-- No change; striping occurs in outermost navbox.
			return wikitext .. orphanCat
		end
		local first, second = cfg.class.navbox_odd_part, cfg.class.navbox_even_part
		if args[cfg.arg.evenodd] then
			if args[cfg.arg.evenodd] == cfg.keyword.evenodd_swap then
				first, second = second, first
			else
				first = args[cfg.arg.evenodd]
				second = first
			end
		end
		local changer
		if first == second then
			changer = first
		else
			local index = 0
			changer = function (code)
				if code == '0' then
					-- Current occurrence is for a group before a nested table.
					-- Set it to first as a valid although pointless class.
					-- The next occurrence will be the first row after a title
					-- in a subgroup and will also be first.
					index = 0
					return first
				end
				index = index + 1
				return index % 2 == 1 and first or second
			end
		end
		local regex = orphanCat:gsub('([%[%]])', '%%%1')
		return (wikitext:gsub(regex, ''):gsub(cfg.marker.regex, changer)) -- () omits gsub count
	end
	
	local function processItem(item, nowrapitems)
		if item:sub(1, 2) == '{|' then
			-- Applying nowrap to lines in a table does not make sense.
			-- Add newlines to compensate for trim of x in |parm=x in a template.
			return '\n' .. item ..'\n'
		end
		if nowrapitems == cfg.keyword.nowrapitems_yes then
			local lines = {}
			for line in (item .. '\n'):gmatch('([^\n]*)\n') do
				local prefix, content = line:match('^([*:;#]+)%s*(.*)')
				if prefix and not content:match(cfg.pattern.nowrap) then
					line = string.format(cfg.nowrap_item, prefix, content)
				end
				table.insert(lines, line)
			end
			item = table.concat(lines, '\n')
		end
		if item:match('^[*:;#]') then
			return '\n' .. item ..'\n'
		end
		return item
	end
	
	local function has_navbar()
		return args[cfg.arg.navbar] ~= cfg.keyword.navbar_off
			and args[cfg.arg.navbar] ~= cfg.keyword.navbar_plain
			and (
				args[cfg.arg.name]
				or mw.getCurrentFrame():getParent():getTitle():gsub(cfg.pattern.sandbox, '')
					~= cfg.pattern.navbox
			)
	end
	
	-- extract text color from css, which is the only permitted inline CSS for the navbar
	local function extract_color(css_str)
		-- return nil because navbar takes its argument into mw.html which handles
		-- nil gracefully, removing the associated style attribute
		return mw.ustring.match(';' .. css_str .. ';', '.*;%s*([Cc][Oo][Ll][Oo][Rr]%s*:%s*.-)%s*;') or nil
	end
	
	local function renderNavBar(titleCell)
		if has_navbar() then
			local navbar = require('Module:Navbar')._navbar
			titleCell:wikitext(navbar{
				[cfg.navbar.name] = args[cfg.arg.name],
				[cfg.navbar.mini] = 1,
				[cfg.navbar.fontstyle] = extract_color(
					(args[cfg.arg.basestyle] or '') .. ';' .. (args[cfg.arg.titlestyle] or '')
				)
			})
		end
	
	end
	
	local function renderTitleRow(tbl)
		if not args[cfg.arg.title] then return end
	
		local titleRow = tbl:tag('tr')
	
		local titleCell = titleRow:tag('th'):attr('scope', 'col')
	
		local titleColspan = 2
		if args[cfg.arg.imageleft] then titleColspan = titleColspan + 1 end
		if args[cfg.arg.image] then titleColspan = titleColspan + 1 end
	
		titleCell
			:cssText(args[cfg.arg.basestyle])
			:cssText(args[cfg.arg.titlestyle])
			:addClass(cfg.class.navbox_title)
			:attr('colspan', titleColspan)
	
		renderNavBar(titleCell)
	
		titleCell
			:tag('div')
				-- id for aria-labelledby attribute
				:attr('id', mw.uri.anchorEncode(args[cfg.arg.title]))
				:addClass(args[cfg.arg.titleclass])
				:css('font-size', '114%')
				:css('margin', '0 4em')
				:wikitext(processItem(args[cfg.arg.title]))
	end
	
	local function getAboveBelowColspan()
		local ret = 2
		if args[cfg.arg.imageleft] then ret = ret + 1 end
		if args[cfg.arg.image] then ret = ret + 1 end
		return ret
	end
	
	local function renderAboveRow(tbl)
		if not args[cfg.arg.above] then return end
	
		tbl:tag('tr')
			:tag('td')
				:addClass(cfg.class.navbox_abovebelow)
				:addClass(args[cfg.arg.aboveclass])
				:cssText(args[cfg.arg.basestyle])
				:cssText(args[cfg.arg.abovestyle])
				:attr('colspan', getAboveBelowColspan())
				:tag('div')
					-- id for aria-labelledby attribute, if no title
					:attr('id', (not args[cfg.arg.title]) and mw.uri.anchorEncode(args[cfg.arg.above]) or nil)
					:wikitext(processItem(args[cfg.arg.above], args[cfg.arg.nowrapitems]))
	end
	
	local function renderBelowRow(tbl)
		if not args[cfg.arg.below] then return end
	
		tbl:tag('tr')
			:tag('td')
				:addClass(cfg.class.navbox_abovebelow)
				:addClass(args[cfg.arg.belowclass])
				:cssText(args[cfg.arg.basestyle])
				:cssText(args[cfg.arg.belowstyle])
				:attr('colspan', getAboveBelowColspan())
				:tag('div')
					:wikitext(processItem(args[cfg.arg.below], args[cfg.arg.nowrapitems]))
	end
	
	local function renderListRow(tbl, index, listnum, listnums_size)
		local row = tbl:tag('tr')
	
		if index == 1 and args[cfg.arg.imageleft] then
			row
				:tag('td')
					:addClass(cfg.class.noviewer)
					:addClass(cfg.class.navbox_image)
					:addClass(args[cfg.arg.imageclass])
					:css('width', '1px')               -- Minimize width
					:css('padding', '0 2px 0 0')
					:cssText(args[cfg.arg.imageleftstyle])
					:attr('rowspan', listnums_size)
					:tag('div')
						:wikitext(processItem(args[cfg.arg.imageleft]))
		end
	
		local group_and_num = andnum('group', listnum)
		local groupstyle_and_num = andnum('groupstyle', listnum)
		if args[group_and_num] then
			local groupCell = row:tag('th')
	
			-- id for aria-labelledby attribute, if lone group with no title or above
			if listnum == 1 and not (args[cfg.arg.title] or args[cfg.arg.above] or args[cfg.arg.group2]) then
				groupCell
					:attr('id', mw.uri.anchorEncode(args[cfg.arg.group1]))
			end
	
			groupCell
				:attr('scope', 'row')
				:addClass(cfg.class.navbox_group)
				:addClass(args[cfg.arg.groupclass])
				:cssText(args[cfg.arg.basestyle])
				-- If groupwidth not specified, minimize width
				:css('width', args[cfg.arg.groupwidth] or '1%')
	
			groupCell
				:cssText(args[cfg.arg.groupstyle])
				:cssText(args[groupstyle_and_num])
				:wikitext(args[group_and_num])
		end
	
		local listCell = row:tag('td')
	
		if args[group_and_num] then
			listCell
				:addClass(cfg.class.navbox_list_with_group)
		else
			listCell:attr('colspan', 2)
		end
	
		if not args[cfg.arg.groupwidth] then
			listCell:css('width', '100%')
		end
	
		local rowstyle  -- usually nil so cssText(rowstyle) usually adds nothing
		if index % 2 == 1 then
			rowstyle = args[cfg.arg.oddstyle]
		else
			rowstyle = args[cfg.arg.evenstyle]
		end
	
		local list_and_num = andnum('list', listnum)
		local listText = inArray(cfg.keyword.subgroups, args[list_and_num])
			and getSubgroup(args, listnum, args[list_and_num]) or args[list_and_num]
		
		local oddEven = cfg.marker.oddeven
		if listText:sub(1, 12) == '</div><table' then
			-- Assume list text is for a subgroup navbox so no automatic striping for this row.
			oddEven = listText:find(cfg.pattern.navbox_title) and cfg.marker.restart or cfg.class.navbox_odd_part
		end
		
		local liststyle_and_num = andnum('liststyle', listnum)
		local listclass_and_num = andnum('listclass', listnum)
		listCell
			:css('padding', '0')
			:cssText(args[cfg.arg.liststyle])
			:cssText(rowstyle)
			:cssText(args[liststyle_and_num])
			:addClass(cfg.class.navbox_list)
			:addClass(cfg.class.navbox_part .. oddEven)
			:addClass(args[cfg.arg.listclass])
			:addClass(args[listclass_and_num])
			:tag('div')
				:css('padding',
					(index == 1 and args[cfg.arg.list1padding]) or args[cfg.arg.listpadding] or '0 0.25em'
				)
				:wikitext(processItem(listText, args[cfg.arg.nowrapitems]))
	
		if index == 1 and args[cfg.arg.image] then
			row
				:tag('td')
					:addClass(cfg.class.noviewer)
					:addClass(cfg.class.navbox_image)
					:addClass(args[cfg.arg.imageclass])
					:css('width', '1px')               -- Minimize width
					:css('padding', '0 0 0 2px')
					:cssText(args[cfg.arg.imagestyle])
					:attr('rowspan', listnums_size)
					:tag('div')
						:wikitext(processItem(args[cfg.arg.image]))
		end
	end
	
	local function has_list_class(htmlclass)
		local patterns = {
			'^' .. htmlclass .. '$',
			'%s' .. htmlclass .. '$',
			'^' .. htmlclass .. '%s',
			'%s' .. htmlclass .. '%s'
		}
		
		for arg, _ in pairs(args) do
			if type(arg) == 'string' and mw.ustring.find(arg, cfg.pattern.class) then
				for _, pattern in ipairs(patterns) do
					if mw.ustring.find(args[arg] or '', pattern) then
						return true
					end
				end
			end
		end
		return false
	end
	
	-- there are a lot of list classes in the wild, so we add their TemplateStyles
	local function add_list_styles()
		local frame = mw.getCurrentFrame()
		local function add_list_templatestyles(htmlclass, templatestyles)
			if has_list_class(htmlclass) then
				return frame:extensionTag{
					name = 'templatestyles', args = { src = templatestyles }
				}
			else
				return ''
			end
		end
		
		local hlist_styles = add_list_templatestyles('hlist', cfg.hlist_templatestyles)
		local plainlist_styles = add_list_templatestyles('plainlist', cfg.plainlist_templatestyles)
		
		-- a second workaround for [[phab:T303378]]
		-- when that issue is fixed, we can actually use has_navbar not to emit the
		-- tag here if we want
		if has_navbar() and hlist_styles == '' then
			hlist_styles = frame:extensionTag{
				name = 'templatestyles', args = { src = cfg.hlist_templatestyles }
			}
		end
		
		-- hlist -> plainlist is best-effort to preserve old Common.css ordering.
		-- this ordering is not a guarantee because most navboxes will emit only
		-- one of these classes [hlist_note]
		return hlist_styles .. plainlist_styles
	end
	
	local function needsHorizontalLists(border)
		if border == cfg.keyword.border_subgroup or args[cfg.arg.tracking] == cfg.keyword.tracking_no then
			return false
		end
		return not has_list_class(cfg.pattern.hlist) and not has_list_class(cfg.pattern.plainlist)
	end
	
	local function hasBackgroundColors()
		for _, key in ipairs({cfg.arg.titlestyle, cfg.arg.groupstyle,
			cfg.arg.basestyle, cfg.arg.abovestyle, cfg.arg.belowstyle}) do
			if tostring(args[key]):find('background', 1, true) then
				return true
			end
		end
		return false
	end
	
	local function hasBorders()
		for _, key in ipairs({cfg.arg.groupstyle, cfg.arg.basestyle,
			cfg.arg.abovestyle, cfg.arg.belowstyle}) do
			if tostring(args[key]):find('border', 1, true) then
				return true
			end
		end
		return false
	end
	
	local function isIllegible()
		local styleratio = require('Module:Color contrast')._styleratio
		for key, style in pairs(args) do
			if tostring(key):match(cfg.pattern.style) then
				if styleratio{mw.text.unstripNoWiki(style)} < 4.5 then
					return true
				end
			end
		end
		return false
	end
	
	local function getTrackingCategories(border)
		local cats = {}
		if needsHorizontalLists(border) then table.insert(cats, cfg.category.horizontal_lists) end
		if hasBackgroundColors() then table.insert(cats, cfg.category.background_colors) end
		if isIllegible() then table.insert(cats, cfg.category.illegible) end
		if hasBorders() then table.insert(cats, cfg.category.borders) end
		return cats
	end
	
	local function renderTrackingCategories(builder, border)
		local title = mw.title.getCurrentTitle()
		if title.namespace ~= 10 then return end -- not in template space
		local subpage = title.subpageText
		if subpage == cfg.keyword.subpage_doc or subpage == cfg.keyword.subpage_sandbox
			or subpage == cfg.keyword.subpage_testcases then return end
	
		for _, cat in ipairs(getTrackingCategories(border)) do
			builder:wikitext('[[Category:' .. cat .. ']]')
		end
	end
	
	local function renderMainTable(border, listnums)
		local tbl = mw.html.create('table')
			:addClass(cfg.class.nowraplinks)
			:addClass(args[cfg.arg.bodyclass])
	
		local state = args[cfg.arg.state]
		if args[cfg.arg.title] and state ~= cfg.keyword.state_plain and state ~= cfg.keyword.state_off then
			if state == cfg.keyword.state_collapsed then
				state = cfg.class.collapsed
			end
			tbl
				:addClass(cfg.class.collapsible)
				:addClass(state or cfg.class.autocollapse)
		end
	
		tbl:css('border-spacing', 0)
		if border == cfg.keyword.border_subgroup or border == cfg.keyword.border_none then
			tbl
				:addClass(cfg.class.navbox_subgroup)
				:cssText(args[cfg.arg.bodystyle])
				:cssText(args[cfg.arg.style])
		else  -- regular navbox - bodystyle and style will be applied to the wrapper table
			tbl
				:addClass(cfg.class.navbox_inner)
				:css('background', 'transparent')
				:css('color', 'inherit')
		end
		tbl:cssText(args[cfg.arg.innerstyle])
	
		renderTitleRow(tbl)
		renderAboveRow(tbl)
		local listnums_size = #listnums
		for i, listnum in ipairs(listnums) do
			renderListRow(tbl, i, listnum, listnums_size)
		end
		renderBelowRow(tbl)
	
		return tbl
	end
	
	local function add_navbox_styles(hiding_templatestyles)
		local frame = mw.getCurrentFrame()
		-- This is a lambda so that it doesn't need the frame as a parameter
		local function add_user_styles(templatestyles)
			if not isblank(templatestyles) then
				return frame:extensionTag{
					name = 'templatestyles', args = { src = templatestyles }
				}
			end
			return ''
		end
	
		-- get templatestyles. load base from config so that Lua only needs to do
		-- the work once of parser tag expansion
		local base_templatestyles = cfg.templatestyles
		local templatestyles = add_user_styles(args[cfg.arg.templatestyles])
		local child_templatestyles = add_user_styles(args[cfg.arg.child_templatestyles])
	
		-- The 'navbox-styles' div exists to wrap the styles to work around T200206
		-- more elegantly. Instead of combinatorial rules, this ends up being linear
		-- number of CSS rules.
		return mw.html.create('div')
			:addClass(cfg.class.navbox_styles)
			:wikitext(
				add_list_styles() .. -- see [hlist_note] applied to 'before base_templatestyles'
				base_templatestyles ..
				templatestyles ..
				child_templatestyles ..
				table.concat(hiding_templatestyles)
			)
			:done()
	end
	
	-- work around [[phab:T303378]]
	-- for each arg: find all the templatestyles strip markers, insert them into a
	-- table. then remove all templatestyles markers from the arg
	local function move_hiding_templatestyles(args)
		local gfind = string.gfind
		local gsub = string.gsub
		local templatestyles_markers = {}
		local strip_marker_pattern = '(\127[^\127]*UNIQ%-%-templatestyles%-%x+%-QINU[^\127]*\127)'
		for k, arg in pairs(args) do
			for marker in gfind(arg, strip_marker_pattern) do
				table.insert(templatestyles_markers, marker)
			end
			args[k] = gsub(arg, strip_marker_pattern, '')
		end
		return templatestyles_markers
	end
	
	local hiding_templatestyles = move_hiding_templatestyles(args)
	local listnums = {}
	
	for k, _ in pairs(args) do
		if type(k) == 'string' then
			local listnum = k:match(cfg.pattern.listnum)
			if listnum then table.insert(listnums, tonumber(listnum)) end
		end
	end
	table.sort(listnums)

	local border = mw.text.trim(args[cfg.arg.border] or args[1] or '')
	if border == cfg.keyword.border_child then
		border = cfg.keyword.border_subgroup
	end

	-- render the main body of the navbox
	local tbl = renderMainTable(border, listnums)

	local res = mw.html.create()
	-- render the appropriate wrapper for the navbox, based on the border param

	if border == cfg.keyword.border_none then
		res:node(add_navbox_styles(hiding_templatestyles))
		local nav = res:tag('div')
			:attr('role', 'navigation')
			:node(tbl)
		-- aria-labelledby title, otherwise above, otherwise lone group
		if args[cfg.arg.title] or args[cfg.arg.above] or (args[cfg.arg.group1]
			and not args[cfg.arg.group2]) then
			nav:attr(
				'aria-labelledby',
				mw.uri.anchorEncode(
					args[cfg.arg.title] or args[cfg.arg.above] or args[cfg.arg.group1]
				)
			)
		else
			nav:attr('aria-label', cfg.aria_label)
		end
	elseif border == cfg.keyword.border_subgroup then
		-- We assume that this navbox is being rendered in a list cell of a
		-- parent navbox, and is therefore inside a div with padding:0em 0.25em.
		-- We start with a </div> to avoid the padding being applied, and at the
		-- end add a <div> to balance out the parent's </div>
		res
			:wikitext('</div>')
			:node(tbl)
			:wikitext('<div>')
	else
		res:node(add_navbox_styles(hiding_templatestyles))
		local nav = res:tag('div')
			:attr('role', 'navigation')
			:addClass(cfg.class.navbox)
			:addClass(args[cfg.arg.navboxclass])
			:cssText(args[cfg.arg.bodystyle])
			:cssText(args[cfg.arg.style])
			:css('padding', '3px')
			:node(tbl)
		-- aria-labelledby title, otherwise above, otherwise lone group
		if args[cfg.arg.title] or args[cfg.arg.above]
			or (args[cfg.arg.group1] and not args[cfg.arg.group2]) then
			nav:attr(
				'aria-labelledby',
				mw.uri.anchorEncode(args[cfg.arg.title] or args[cfg.arg.above] or args[cfg.arg.group1])
			)
		else
			nav:attr('aria-label', cfg.aria_label)
		end
	end

	if (args[cfg.arg.nocat] or cfg.keyword.nocat_false):lower() == cfg.keyword.nocat_false then
		renderTrackingCategories(res, border)
	end
	return striped(tostring(res), border)
end

function p._withCollapsibleGroups(pargs)
	-- table for args passed to navbox
	local targs = {}

	-- process args
	local passthroughLocal = {
		[cfg.arg.bodystyle] = true,
		[cfg.arg.border] = true,
		[cfg.arg.style] = true,
	}
	for k,v in pairs(pargs) do
		if k and type(k) == 'string' then
			if passthrough[k] or passthroughLocal[k] then
				targs[k] = v
			elseif (k:match(cfg.pattern.num)) then
				local n = k:match(cfg.pattern.num)
				local list_and_num = andnum('list', n)
				if ((k:match(cfg.pattern.listnum) or k:match(cfg.pattern.contentnum))
						and targs[list_and_num] == nil
						and pargs[andnum('group', n)] == nil
						and pargs[andnum('sect', n)] == nil
						and pargs[andnum('section', n)] == nil) then
					targs[list_and_num] = concatstrings({
						pargs[list_and_num] or '',
						pargs[andnum('content', n)] or ''
					})
					if (targs[list_and_num] and inArray(cfg.keyword.subgroups, targs[list_and_num])) then
						targs[list_and_num] = getSubgroup(pargs, n, targs[list_and_num])
					end
				elseif ((k:match(cfg.pattern.groupnum) or k:match(cfg.pattern.sectnum) or k:match(cfg.pattern.sectionnum))
						and targs[list_and_num] == nil) then
					local titlestyle = concatstyles({
						pargs[cfg.arg.groupstyle] or '',
						pargs[cfg.arg.secttitlestyle] or '', 
						pargs[andnum('groupstyle', n)] or '', 
						pargs[andnum('sectiontitlestyle', n)] or ''
					})
					local liststyle = concatstyles({
						pargs[cfg.arg.liststyle] or '',
						pargs[cfg.arg.contentstyle] or '', 
						pargs[andnum('liststyle', n)] or '', 
						pargs[andnum('contentstyle', n)] or ''
					})
					local title = concatstrings({
						pargs[andnum('group', n)] or '',
						pargs[andnum('sect', n)] or '',
						pargs[andnum('section', n)] or ''
					})
					local list = concatstrings({
						pargs[list_and_num] or '', 
						pargs[andnum('content', n)] or ''
					})
					if list and inArray(cfg.keyword.subgroups, list) then
						list = getSubgroup(pargs, n, list)
					end
					local abbr_and_num = andnum('abbr', n)
					local state = (pargs[abbr_and_num] and pargs[abbr_and_num] == pargs[cfg.arg.selected]) 
						and cfg.keyword.state_uncollapsed
						or (pargs[andnum('state', n)] or cfg.keyword.state_collapsed)
					
					targs[list_and_num] =p._navbox({
						cfg.keyword.border_child,
						[cfg.arg.navbar] = cfg.keyword.navbar_plain,
						[cfg.arg.state] = state,
						[cfg.arg.basestyle] = pargs[cfg.arg.basestyle],
						[cfg.arg.title] = title,
						[cfg.arg.titlestyle] = titlestyle,
						[andnum('list', 1)] = list,
						[cfg.arg.liststyle] = liststyle,
						[cfg.arg.listclass] = pargs[andnum('listclass', n)],
						[cfg.arg.image] = pargs[andnum('image', n)],
						[cfg.arg.imageleft] = pargs[andnum('imageleft', n)],
						[cfg.arg.listpadding] = pargs[cfg.arg.listpadding]
					})
				end
			end
		end
	end
	-- ordering of style and bodystyle
	targs[cfg.arg.style] = concatstyles({targs[cfg.arg.style] or '', targs[cfg.arg.bodystyle] or ''})
	targs[cfg.arg.bodystyle] = nil
	
	-- child or subgroup
	if targs[cfg.arg.border] == nil then targs[cfg.arg.border] = pargs[1] end

	return p._navbox(targs)
end

function p._withColumns(pargs)
	-- table for args passed to navbox
	local targs = {}
	
	-- tables of column numbers
	local colheadernums = {}
	local colnums = {}
	local colfooternums = {}
	
	-- process args
	local passthroughLocal = {
		[cfg.arg.evenstyle]=true,
		[cfg.arg.groupstyle]=true,
		[cfg.arg.liststyle]=true,
		[cfg.arg.oddstyle]=true,
		[cfg.arg.state]=true,
	}
	for k,v in pairs(pargs) do
		if passthrough[k] or passthroughLocal[k] then
			targs[k] = v
		elseif type(k) == 'string' then
			if k:match(cfg.pattern.listnum) then
				local n = k:match(cfg.pattern.listnum)
				targs[andnum('liststyle', n + 2)] = pargs[andnum('liststyle', n)]
				targs[andnum('group', n + 2)] = pargs[andnum('group', n)]
				targs[andnum('groupstyle', n + 2)] = pargs[andnum('groupstyle', n)]
				if v and inArray(cfg.keyword.subgroups, v) then
					targs[andnum('list', n + 2)] = getSubgroup(pargs, n, v)
				else
					targs[andnum('list', n + 2)] = v
				end
			elseif (k:match(cfg.pattern.colheadernum) and v ~= '') then
				table.insert(colheadernums, tonumber(k:match(cfg.pattern.colheadernum)))
			elseif (k:match(cfg.pattern.colnum) and v ~= '') then
				table.insert(colnums, tonumber(k:match(cfg.pattern.colnum)))
			elseif (k:match(cfg.pattern.colfooternum) and v ~= '') then
				table.insert(colfooternums, tonumber(k:match(cfg.pattern.colfooternum)))
			end
		end
	end
	table.sort(colheadernums)
	table.sort(colnums)
	table.sort(colfooternums)
		
	-- HTML table for list1
	local coltable = mw.html.create( 'table' ):attr('class', 'navbox-columns-table')
	local row, col
	
	local tablestyle = ( (#colheadernums > 0) or (not isblank(pargs[cfg.arg.fullwidth])) )
		and 'width:100%'
		or 'width:auto; margin-left:auto; margin-right:auto'
	
	coltable:attr('style', concatstyles({
		'border-spacing: 0px; text-align:left',
		tablestyle,
		pargs[cfg.arg.coltablestyle] or ''
	}))
	
	--- Header row ---
	if (#colheadernums > 0) then
		row = coltable:tag('tr')
		for k, n in ipairs(colheadernums) do
			col = row:tag('td'):attr('class', 'navbox-abovebelow')
			col:attr('style', concatstyles({
				(k > 1) and 'border-left:2px solid #fdfdfd' or '',
				'font-weight:bold',
				pargs[cfg.arg.colheaderstyle] or '',
				pargs[andnum('colheaderstyle', n)] or ''
			}))
			col:attr('colspan', tonumber(pargs[andnum('colheadercolspan', n)]))
			col:wikitext(pargs[andnum('colheader', n)])
		end
	end
	
	--- Main columns ---
	row = coltable:tag('tr'):attr('style', 'vertical-align:top')
	for k, n in ipairs(colnums) do
		if k == 1 and isblank(pargs[andnum('colheader', 1)])
				and isblank(pargs[andnum('colfooter', 1)])
				and isblank(pargs[cfg.arg.fullwidth]) then
			local nopad = inArray(
				{'off', '0', '0em', '0px'},
				mw.ustring.gsub(pargs[cfg.arg.padding] or '', '[;%%]', ''))
			if not nopad then
				row:tag('td'):wikitext('&nbsp;&nbsp;&nbsp;')
					:attr('style', 'width:'..(pargs[cfg.arg.padding] or '5em')..';')
			end
		end
		col = row:tag('td'):attr('class', 'navbox-list')
		col:attr('style', concatstyles({
			(k > 1) and 'border-left:2px solid #fdfdfd' or '',
			'padding:0px',
			pargs[cfg.arg.colstyle] or '',
			((n%2 == 0) and pargs[cfg.arg.evencolstyle] or pargs[cfg.arg.oddcolstyle]) or '',
			pargs[andnum('colstyle', n)] or '',
			'width:' .. (pargs[andnum('colwidth', n)] or pargs[cfg.arg.colwidth] or '10em')
		}))
		local wt = pargs[andnum('col', n)]
		if wt and inArray(cfg.keyword.subgroups, wt) then
			local prefix = mw.ustring.gsub(cfg.arg.col_and_num,"%%d","")
			wt = getSubgroup(pargs, n, wt, prefix)
		end
		col:tag('div'):newline():wikitext(wt):newline()
	end
	
	--- Footer row ---
	if (#colfooternums > 0) then
		row = coltable:tag('tr')
		for k, n in ipairs(colfooternums) do
			col = row:tag('td'):attr('class', 'navbox-abovebelow')
			col:attr('style', concatstyles({
				(k > 1) and 'border-left:2px solid #fdfdfd' or '',
				'font-weight:bold',
				pargs[cfg.arg.colfooterstyle] or '',
				pargs[andnum('colfooterstyle', n)] or ''
			}))
			col:attr('colspan', tonumber(pargs[andnum('colfootercolspan', n)]))
			col:wikitext(pargs[andnum('colfooter', n)])
		end
	end
	
	-- assign table to list1
	targs[andnum('list', 1)] = tostring(coltable)
	if isblank(pargs[andnum('colheader', 1)]) 
			and isblank(pargs[andnum('col', 1)])
			and isblank(pargs[andnum('colfooter', 1)]) then
		targs[andnum('list', 1)] = targs[andnum('list', 1)] ..
			'[[' .. cfg.pattern.without_first_col .. ']]'
	end

	-- Other parameters
	targs[cfg.arg.border] = pargs[cfg.arg.border] or pargs[1]
	targs[cfg.arg.evenodd] = (not isblank(pargs[cfg.arg.evenodd])) and pargs[cfg.arg.evenodd] or nil
	targs[cfg.arg.list1padding] = '0px'
	targs[andnum('liststyle', 1)] = 'background:transparent;color:inherit;'
	targs[cfg.arg.style] = concatstyles({pargs[cfg.arg.style], pargs[cfg.arg.bodystyle]})
	targs[cfg.arg.tracking] = 'no'
	
	return p._navbox(targs)
end

-- Template entry points
function p.navbox (frame, boxtype)
	local function readArgs(args, prefix)
		-- Read the arguments in the order they'll be output in, to make references
		-- number in the right order.
		local _
		_ = args[prefix .. cfg.arg.title]
		_ = args[prefix .. cfg.arg.above]
		-- Limit this to 20 as covering 'most' cases (that's a SWAG) and because
		-- iterator approach won't work here
		for i = 1, 20 do
			_ = args[prefix .. andnum('group', i)]
			if inArray(cfg.keyword.subgroups, args[prefix .. andnum('list', i)]) then
				for _, v in ipairs(cfg.keyword.subgroups) do
					readArgs(args, prefix .. v .. i .. "_")
				end
			end
		end
		_ = args[prefix .. cfg.arg.below]
	end

	if not getArgs then
		getArgs = require('Module:Arguments').getArgs
	end
	local args = getArgs(frame, {wrappers = {cfg.pattern[boxtype or 'navbox']}})
	readArgs(args, "")
	args.type = args.type or cfg.keyword[boxtype]
	return p['_navbox'](args)
end

p[cfg.keyword.with_collapsible_groups] = function (frame)
	return p.navbox(frame, 'with_collapsible_groups')
end

p[cfg.keyword.with_columns] = function (frame)
	return p.navbox(frame, 'with_columns')
end

return p