-- This module implements {{archive list}} in Lua, and adds a few -- new features.  -- Process a numeric argument to make sure it is a positive -- integer. local function processNumArg( num )  if num then  num = tonumber( num )  if type( num ) == 'number' then  num = math.floor( num )  if num >= 0 then  return num  end  end  end  return nil end  -- Checks whether a page exists, going through pcall -- in case we are over the expensive function limit. local function checkPageExists( title )  if not title then  error('ไม่มีชื่อเรื่องส่งมาให้ checkPageExists', 2)  end  local noError, titleObject = pcall(mw.title.new, title)  if not noError then  -- If we are over the expensive function limit then assume  -- that the page doesn't exist.  return false  else  if titleObject then  return titleObject.exists  else  return false -- Return false if given a bad title.  end  end end  -- Checks every nth archive to see if it exists, and returns the -- number of the first archive that doesn't exist. It is -- necessary to do this in batches because each check is an -- expensive function call, and we want to avoid making too many -- of them so as not to go over the expensive function limit. local function checkArchives( prefix, n, start )  local i = start  local exists = true  while exists do  exists = checkPageExists( prefix .. tostring( i ) )  if exists then  i = i + n  end  end  return i end  -- Return the biggest archive number, using checkArchives() -- and starting in intervals of 1000. This should get us a -- maximum of 500,000 possible archives before we hit the -- expensive function limit. local function getBiggestArchiveNum( prefix, max )  -- Return the value for max if it is specified.  max = processNumArg( max )  if max then  return max  end   -- Otherwise, detect the largest archive number.  local check1000 = checkArchives( prefix, 1000, 1 )  if check1000 == 1 then  return 0 -- Return 0 if no archives were found.  end  local check200 = checkArchives( prefix, 200, check1000 - 1000 )  local check50 = checkArchives( prefix, 50, check200 - 200 )  local check10 = checkArchives( prefix, 10, check50 - 50 )  local check1 = checkArchives( prefix, 1, check10 - 10 )  -- check1 is the first page that doesn't exist, so we want to  -- subtract it by one to find the biggest existing archive.  return check1 - 1 end  -- Get the archive link prefix (the title of the archive pages -- minus the number). local function getPrefix( root, prefix, prefixSpace )  local ret = root or mw.title.getCurrentTitle().prefixedText  ret = ret .. '/'  if prefix then  ret = ret .. prefix  if prefixSpace == 'yes' then  ret = ret .. ' '  end  else  ret = ret .. 'กรุ '  end  return ret end  -- Get the number of archives to put on one line. Set to -- math.huge if there should be no line breaks. local function getLineNum( links, nobr )  local linksToNum = tonumber( links )  local lineNum  if nobr == 'yes' or (links and not linksToNum) then  lineNum = math.huge  -- If links is a number, process it. Negative values and expressions  -- such as links=8/2 produced some interesting values with the old  -- template, but we will ignore those for simplicity.  elseif type(linksToNum) == 'number' and linksToNum >= 0 then  -- The old template rounded down decimals to the nearest integer.  lineNum = math.floor( linksToNum )  if lineNum == 0 then  -- In the old template, values of links between 0 and 0.999  -- suppressed line breaks.  lineNum = math.huge  end  else  lineNum = 10 -- Default to 10 links.  end  return lineNum end  -- Gets the prefix to put before the archive links. local function getLinkPrefix( prefix, space )  -- Get the link prefix.  local ret = ''  if type(prefix) == 'string' then  ret = prefix  if space == 'yes' then  ret = ret .. ' '  end  end  return ret end  -- Get the number to start listing archives from. local function getStart( start )  start = processNumArg( start )  if start then  return start  else  return 1  end end  -- Process the separator parameter. local function getSeparator( sep )  if sep and type(sep) == 'string' then  if sep == 'dot'  or sep =='pipe'  or sep == 'comma'  or sep == 'tpt-languages' then  return mw.message.new( sep .. '-separator' ):plain()  else  return sep  end  else  return nil  end end  -- Generates the list of archive links. glargs.max must be either zero (for -- no archives) or a positive integer value. local function generateLinks( glargs )  if type( glargs ) ~= 'table' or not glargs.max or not glargs.prefix then  error('อาร์กิวเมนต์ที่ส่งมาให้ generateLinks ไม่เพียงพอ', 2)  end  -- If there are no archives yet, return a message and a  -- link to create Archive one.  if glargs.max == 0 then  return 'ยังไม่มีกรุ ([[' .. glargs.prefix .. '1|สร้าง]])'  end  -- Return an html error if the start number is greater than the   -- maximum number.  local start = glargs.start or 1  if start > glargs.max then  return '<span class="error">ค่าเริ่มต้น "'  .. tostring( start )  .. '" มากกว่าจำนวนกรุล่าสุด "'  .. tostring( glargs.max )  .. '"</span>'  end  local linkPrefix = glargs.linkPrefix or ''  local sep = glargs.sep or mw.message.new( 'comma-separator' ):plain()  local lineNum = glargs.lineNum or 10  local lineSep = glargs.lineSep or '<br />'   -- Generate the archive links.  local lineCounter = 1 -- The counter to see whether we need a line break or not.  local ret = {} -- A table containing the strings to be returned.  for archiveNum = start, glargs.max do  local link = mw.ustring.format(  '[[%s%d|%s%d]]',  glargs.prefix, archiveNum, linkPrefix, archiveNum  )  table.insert( ret, link )  -- If we don't need a new line, output a comma. We don't need  -- a comma after the last link.   if lineCounter < lineNum and archiveNum < glargs.max then  table.insert( ret, sep )  lineCounter = lineCounter + 1  -- Output new lines if needed. We don't need a new line after  -- the last link.  elseif lineCounter >= lineNum and archiveNum < glargs.max then  table.insert( ret, lineSep )  lineCounter = 1  end  end  return table.concat( ret ) end  -- Get the archive data and pass it to generateLinks(). local function _main( args )  local prefix = getPrefix( args.root, args.prefix, args.prefixspace )  local max = getBiggestArchiveNum( prefix, args.max )  local lineNum = getLineNum( args.links, args.nobr )  local linkPrefix = getLinkPrefix( args.linkprefix, args.linkprefixspace )  local start = getStart( args.start )  local sep = getSeparator( args.sep )  local lineSep = getSeparator( args.linesep )  local glargs = {  start = start,  max = max,  prefix = prefix,  linkPrefix = linkPrefix,  sep = sep,  lineNum = lineNum,  lineSep = lineSep  }  return generateLinks( glargs ) end  -- A wrapper function to make getBiggestArchiveNum() available from -- #invoke. local function _count( args )  local prefix = getPrefix( args.root, args.prefix, args.prefixspace )  local archiveMax = getBiggestArchiveNum( prefix )  return archiveMax end  function makeWrapper( func )  return function( frame )  -- If we are being called from #invoke, get the args from #invoke  -- if they exist, or else get the arguments passed to the parent  -- frame. Otherwise, assume the arguments are being passed directly  -- in from another module or from the debug console.  local origArgs  if frame == mw.getCurrentFrame() then  origArgs = frame:getParent().args  for k, v in pairs( frame.args ) do  origArgs = frame.args  break  end  else  origArgs = frame  end   -- Ignore blank values for parameters other than "links",  -- which functions differently depending on whether it is  -- blank or absent.  local args = {}  for k, v in pairs( origArgs ) do  if k == 'links' or v ~= '' then  args[k] = v  end  end   return func( args )  end end  return {  main = makeWrapper( _main ),  count = makeWrapper( _count ) }