# Module:Gallery

-- This module implements  

local p = {}  

local templatestyles = 'Module:Gallery/styles.css'  
local yesno = require('Module:Yesno')  

local function trim(s)  
return mw.ustring.gsub(mw.ustring.gsub(s, '%s', ' '), '^%s*(.-)%s*$', '%1')  
end  

local tracking, preview  

local function checkarg(k,v)  
if k and type(k) == 'string' then  
if k == 'align' or k == 'state' or k == 'style' or k == 'title' or  
k == 'width' or k == 'height' or k == 'lines' or k == 'whitebg' or  
k == 'mode' or k == 'footer' or k == 'perrow' or k == 'noborder' or  
k:match('^alt%d+$') or k:match('^%d+$') then  
-- valid  
elseif k == 'captionstyle' then  
if not v:match('^text%-align%s*:%s*[;%s]*$') then  
table.insert(tracking, '')  
end  
else  
-- invalid  
local vlen = mw.ustring.len(k)  
k = mw.ustring.sub(k, 1, (vlen < 25) and vlen or 25)  
k = mw.ustring.gsub(k, '[^%w\-_ ]', '?')  
table.insert(tracking, '')  
table.insert(preview, '"' .. k .. '"')  
end  
end  
end  

function p.gallery  
-- If called via #invoke, use the args passed into the invoking template.  
-- Otherwise, for testing purposes, assume args are being passed directly in.  
local origArgs = (type(.getParent) == 'function') and :getParent.args or  

-- ParserFunctions considers the empty string to be false, so to preserve the previous  
-- behavior of , change any empty arguments to nil, so Lua will consider  
-- them false too.  
local args = {}  
tracking, preview = {}, {}  
for k, v in pairs(origArgs) do  
if v ~= '' then  
args[k] = v  
checkarg(k,v)  
end  
end  

if (args.mode or *) == 'packed' and (args.align or *) == '' then  
args.  
end  

local tbl = mw.html.create('div')  
tbl:addClass('mod-gallery')  

if args.state then  
tbl  
:addClass('mod-gallery-collapsible')  
:addClass('collapsible')  
:addClass(args.state)  
end  

if args.style then  
tbl:cssText(args.style)  
else  
tbl:addClass('mod-gallery-default')  
end  

if args.align then  
tbl:addClass('mod-gallery-' .. args.align:lower)  
end  

if args.title then  
tbl:tag('div')  
:addClass('title')  
:tag('div')  
:wikitext(args.title)  
end  

local gargs = {}  
gargs['class'] = 'nochecker' .. (args.noborder and '' or ' bordered-images')  
gargs['widths'] = tonumber(args.width) or 180  
gargs['heights'] = tonumber(args.height) or 180  
gargs['style'] = args.captionstyle  
gargs['perrow'] = args.perrow  
gargs['mode'] = args.mode  
if yesno(args.whitebg or 'yes') then  
gargs['class'] = gargs['class'] .. ' whitebg'  
end  

local gallery = {}  

local imageCount = math.ceil(#args / 2)  

for i = 1, imageCount do  
local img = trim(args[i*2 - 1] or '')  
local caption = trim(args[i*2] or '')  
local alt = trim(args['alt' .. i] or '')  
if img ~= '' then  
table.insert(gallery, img .. (alt ~= * and ('|alt=' .. alt) or *) .. '|' .. caption )  
end  
end  

tbl:tag('div')  
:addClass('main')  
:tag('div')  
:wikitext(  
:extensionTag{ name = 'gallery', content = '\n' .. table.concat(gallery,'\n'), args = gargs}  

if args.footer then  
tbl:tag('div')  
:addClass('footer')  
:tag('div')  
:wikitext(args.footer)  
end  

local trackstr = (#tracking > 0) and table.concat(tracking, *) or *  
if #preview > 0 then  
trackstr = require('Module:If preview')._warning({  
'Unknown parameters ' .. table.concat(preview, '; ') .. '.'  
}) .. trackstr  
end  

return :extensionTag{ name = 'templatestyles', args = { src = templatestyles} } .. tostring(tbl) .. trackstr  
end  

return p