Module:Multiple image
-- implements [[template:multiple image]]
 local p = {}
 
 local autoscaledimages
 local nonautoscaledimages
 
 local function isnotempty(s)
 	return s and s:match( '^%s*(.-)%s*$' ) ~= ''
 end
 
 local function removepx(s)
 	return tostring(s or ''):match('^(.*)[Pp][Xx]%s*$') or s
 end
 
 local function getdimensions(s, w, h)
 	if tonumber(w) and tonumber(h) then
 		nonautoscaledimages = true
 		return tonumber(w), tonumber(h)
 	end
 	local file = s and mw.title.new('File:' .. mw.uri.decode(mw.ustring.gsub(s,'%|.*$',''), 'WIKI'))
 	file = file and file.file or {width = 0, height = 0}
 	w = tonumber(file.width) or 0
 	h = tonumber(file.height) or 0
 	autoscaledimages = true
 	return w, h
 end
 
 local function renderImageCell(image, width, height, link, alt, thumbtime, caption, textalign, istyle, border)
 	local root = mw.html.create('')
 
 	local altstr = '|alt=' .. (alt or '')
 	local linkstr = link and ('|link=' .. link) or ''
 	local widthstr = '|' .. tostring(width) .. 'px'
 	local thumbtimestr = ''
 
 	if widthstr == '|-nanpx' then
 		widthstr = ''
 	end
 	if isnotempty( thumbtime ) then
 		thumbtimestr = '|thumbtime=' .. thumbtime
 	end
 
 	local imagediv = root:tag('div')
 	imagediv:addClass((border ~= 'infobox') and 'thumbimage' or nil)
 	imagediv:cssText(istyle)
 	if( height ) then
 		imagediv:css('height', tostring(height) .. 'px')
 		imagediv:css('overflow', 'hidden')
 	end
 	imagediv:wikitext('[[file:' .. image .. widthstr .. linkstr .. altstr .. thumbtimestr .. ']]')
 	if isnotempty(caption) then
 		local captiondiv = root:tag('div')
 		captiondiv:addClass((border ~= 'infobox') and 'thumbcaption' or nil)
 		if isnotempty(textalign) then
 			captiondiv:addClass('text-align-' .. textalign)
 		end
 		captiondiv:wikitext(caption)
 	end
 	return tostring(root)
 end
 
 local function getWidth(w1, w2)
 	local w
 	if isnotempty(w1) then
 		w = tonumber(w1)
 	elseif isnotempty(w2) then
 		w = tonumber(w2)
 	end
 	return w or 200
 end
 
 local function getPerRow(pstr, ic)
 	-- split string into array using any non-digit as a dilimiter
 	local pr = mw.text.split(pstr or '', '[^%d][^%d]*')
 	-- if split failed, assume a single row
 	if (#pr &lt; 1) then
 		pr = {tostring(ic)}
 	end
 	-- convert the array of strings to an array of numbers,
 	-- adding any implied/missing numbers at the end of the array
 	local r = 1
 	local thisrow = tonumber(pr[1] or ic) or ic
 	local prownum = {}
 	while( ic &gt; 0 ) do
 		prownum[r] = thisrow
 		ic = ic - thisrow
 		r = r + 1
 		-- use the previous if the next is missing and
 		-- make sure we don't overstep the number of images
 		thisrow = math.min(tonumber(pr[r] or thisrow) or ic, ic)
 	end
 	return prownum
 end
 
 local function renderMultipleImages(frame)
 	local pargs = frame:getParent().args
 	local args = frame.args
 	local width = removepx(pargs['width'] or '')
 	local dir = pargs['direction'] or ''
 	local border = pargs['border'] or args['border'] or ''
 	local align = pargs['align'] or args['align'] or (border == 'infobox' and 'center' or '')
 	local capalign = pargs['caption_align'] or args['caption_align'] or ''
 	local totalwidth = removepx(pargs['total_width'] or args['total_width'] or '')
 	local imgstyle = pargs['image_style'] or args['image_style']
 	local header = pargs['header'] or pargs['title'] or ''
 	local footer = pargs['footer'] or ''
 	local imagegap = tonumber(pargs['image_gap'] or '1') or 1
 	local perrow = nil
 	local thumbclass = {
 		[&quot;left&quot;] = 'tleft',
 		[&quot;none&quot;] = 'tnone',
 		[&quot;center&quot;] = 'tnone',
 		[&quot;centre&quot;] = 'tnone',
 		[&quot;right&quot;] = 'tright'
 		}
 
 	-- find all the nonempty images
 	local imagenumbers = {}
 	local imagecount = 0
 	for k, v in pairs( pargs ) do
 		local i = tonumber(tostring(k):match( '^%s*image([%d]+)%s*$' ) or '0')
 		if( i &gt; 0 and isnotempty(v) ) then
 			table.insert( imagenumbers, i)
 			imagecount = imagecount + 1
 		end
 	end
 
 	-- sort the imagenumbers
 	table.sort(imagenumbers)
 
 	-- create an array with the number of images per row
 	perrow = getPerRow(dir == 'vertical' and '1' or pargs['perrow'], imagecount)
 
 	-- compute the number of rows
 	local rowcount = #perrow
 
 	-- store the image widths and compute row widths and maximum row width
 	local heights = {}
 	local widths = {}
 	local widthmax = 0
 	local widthsum = {}
 	local k = 0
 	for r=1,rowcount do
 		widthsum[r] = 0
 		for c=1,perrow[r] do
 			k = k + 1
 			if( k &lt;= imagecount ) then
 				local i = imagenumbers[k]
 				if( isnotempty(totalwidth) ) then
 					widths[k], heights[k] = getdimensions(pargs['image' .. i], pargs['width' .. i], pargs['height' .. i])
 				else
 					widths[k] = getWidth(width, pargs['width' .. i])
 				end
 				widthsum[r] = widthsum[r] + widths[k]
 			end
 		end
 		widthmax = math.max(widthmax, widthsum[r])
 	end
 
 	-- make sure the gap is non-negative
 	if imagegap &lt; 0 then imagegap = 0 end
 
 	-- if total_width has been specified, rescale the image widths
 	if( isnotempty(totalwidth) ) then
 		totalwidth = tonumber(totalwidth)
 		widthmax = 0
 		local k = 0
 		for r=1,rowcount do
 			local koffset = k
 			local tw = totalwidth - (3 + imagegap) * (perrow[r] - 1) - 12
 			local ar = {}
 			local arsum = 0
 			for j=1,perrow[r] do
 				k = k + 1
 				if( k&lt;= imagecount ) then
 					local i = imagenumbers[k]
 					local h = heights[k] or 0
 					if (h &gt; 0) then
 						ar[j] = widths[k]/h
 						heights[k] = h
 					else
 						ar[j] = widths[k]/100
 					end
 					arsum = arsum + ar[j]
 				end
 			end
 			local ht = tw/arsum
 			local ws = 0
 			k = koffset
 			for j=1,perrow[r] do
 				k = k + 1
 				if( k&lt;= imagecount ) then
 					local i = imagenumbers[k]
 					widths[k] = math.floor(ar[j]*ht + 0.5)
 					ws = ws + widths[k]
 					if heights[k] then
 						heights[k] = math.floor(ht)
 					end
 				end
 			end
 			widthsum[r] = ws
 			widthmax = math.max(widthmax, widthsum[r])
 		end
 	end
 
 	-- start building the array of images, if there are images
 	if( imagecount &gt; 0 ) then
 		-- compute width of outer div
 		local bodywidth = 0
 		for r=1,rowcount do
 			if( widthmax == widthsum[r] ) then
 				bodywidth = widthmax + (3 + imagegap) * (perrow[r] - 1) + 12
 			end
 		end
 		-- The body has a min-width of 100, which needs to be taken into account on specific widths
 		bodywidth = math.max( 100, bodywidth - 8);
 
 		local bg = pargs['background color'] or ''
 		-- create the array of images
 		local root = mw.html.create('div')
 		root:addClass('thumb')
 		root:addClass('tmulti')
 		-- root:addClass('tmulti-sandbox')
 		root:addClass(thumbclass[align] or 'tright')
 
 		if( align == 'center' or align == 'centre' ) then
 			root:addClass('center')
 		end
 		if( bg ~= '' ) then
 			root:css('background-color', bg)
 		end
 
 		local div = root:tag('div')
 		div:addClass((border ~= 'infobox') and 'thumbinner multiimageinner' or 'multiimageinner')
 		div:css('width', tostring(bodywidth) .. 'px')
 			:css('max-width', tostring(bodywidth) .. 'px')
 		if( bg ~= '' ) then
 			div:css('background-color', bg)
 		end
 		if( border == 'infobox' or border == 'none') then
 			div:css('border', 'none')
 		end
 		-- add the header
 		if( isnotempty(header) ) then
 			div:tag('div')
 				:addClass('trow')
 				:tag('div')
 					:addClass('theader')
 					:css('text-align', pargs['header_align'])
 					:css('background-color', 
 						(pargs['header_background'] ~= '') and pargs['header_background'] or nil)
 					:wikitext(header)
 		end
 		-- loop through the images
 		local k = 0
 		for r=1,rowcount do
 			local rowdiv = div:tag('div'):addClass('trow');
 			for j=1,perrow[r] do
 				k = k + 1
 				if( k &lt;= imagecount ) then
 					local imagediv = rowdiv:tag('div')
 					imagediv:addClass('tsingle')
 					if bg ~= '' then
 						imagediv:css('background-color', bg);
 					end
 					if imagegap &gt; 1 and k &lt; imagecount then
 						if dir == 'vertical' then
 							imagediv:css('margin-bottom', tostring(imagegap) .. 'px')	
 						elseif j &lt; perrow[r] then
 							imagediv:css('margin-right', tostring(imagegap) .. 'px')
 						end
 					end
 					local i = imagenumbers[k]
 					local img = pargs['image' .. i]
 					local w = widths[k]
 					imagediv:css('width', tostring(2 + w) .. 'px')
 						:css('max-width', tostring(2 + w) .. 'px')
 					imagediv:wikitext(renderImageCell(img, w, heights[k],
 						pargs['link' .. i], pargs['alt' .. i],
 						pargs['thumbtime' .. i], pargs['caption' .. i], capalign, imgstyle, border))
 				end
 			end
 		end
 		-- add the footer
 		if( isnotempty(footer) ) then
 			local falign = string.lower(pargs['footer_align'] or args['footer_align'] or '')
 			falign = (falign == 'centre') and 'center' or falign
 			div:tag('div')
 				:addClass('trow')
 				:css('display', (falign ~= '') and 'flow-root' or 'flex')
 				:tag('div')
 					:addClass((border ~= 'infobox') and 'thumbcaption' or nil)
 					:css('text-align', (falign ~= '') and falign or nil)
 					:css('background-color', 
 						(pargs['footer_background'] ~= '') and pargs['footer_background'] or nil)
 					:wikitext(footer)
 		end
 		return tostring(root)
 	end
 	return ''
 end
 
 function p.render( frame )
 	autoscaledimages = false
 	nonautoscaledimages = false
 
 	return frame:extensionTag {name = 'templatestyles', args = {src = 'Multiple image/styles.css', wrapper = &quot;.tmulti&quot;}}
 		.. renderMultipleImages( frame )
 		.. (autoscaledimages and '[[Category:Pages using multiple image with auto scaled images]]' or '')
 		.. (nonautoscaledimages and '[[Category:Pages using multiple image with manual scaled images]]' or '')
 end
 
 p[''] = function( frame ) return p.render( frame:newChild{title = frame:getTitle()} ) end