-- This module implements 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('No title passed to checkArchiveExists', 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, start, 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.
start = start or 1
local check1000 = checkArchives( prefix, 1000, start )
if check1000 == start 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 .. 'Archive '
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, isLong )
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
if isLong==true then
lineNum = 3 -- Default to 3 links on long
else
lineNum = 10 -- Default to 10 on short
end
end
return lineNum
end  
-- Gets the prefix to put before the archive links.
local function getLinkPrefix( prefix, space, isLong )
-- Get the link prefix.
local ret = ''
if isLong==true then ---- Default of old template for long is 'Archive '
if type(prefix) == 'string' then
if prefix == * then -- * overrides to empty prefix
ret = ''
else
ret = prefix
if space == 'yes' then
ret = ret .. ' '
end
end
else
ret = 'Archive '
end
else --type is not long
if type(prefix) == 'string' then
ret = prefix
if space == 'yes' then
ret = ret .. ' '
end
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('insufficient arguments passed to generateLinks', 2)
end
-- If there are no archives yet, return a message and a
-- link to create Archive one.
if glargs.max == 0 then
if glargs.isLong == true then
glargs.max = 1 -- One archive redlink is displayed for Long format
else -- Short error and a creat link is displayed for short
return 'no archives yet (create)'
end
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>Start value "'
.. tostring( start )
.. '" is greater than the most recent archive number "'
.. tostring( glargs.max )
.. '".</span>'
end
local linkPrefix = glargs.linkPrefix or ''
local lineNum = glargs.lineNum or 10
local sep = '' -- Long default separator is cell elements, short is ', '
local lineSep = '' -- Long default linebreak is row elements short is '\n'
if glargs.isLong==true then
sep = glargs.sep or ''
sep = sep .. '</td><td>'
lineSep = glargs.lineSep or ''
lineSep = lineSep .. '</td></tr><tr><td>'
else
sep = glargs.sep or mw.message.new( 'comma-separator' ):plain
lineSep = glargs.lineSep or '
'
end
-- 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.
if glargs.isLong == true then --Long version is a table
table.insert(ret, "<table style=\"width: 100%; padding: ; text-align: ; background-color: transparent;\"><tr><td>")
end
for archiveNum = start, glargs.max do
local link = mw.ustring.format(
'%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
if glargs.isLong == true then --Long version is a table
table.insert(ret, "</td></tr></table>")
end
return table.concat( ret )
end  
-- Determine if format should be long
local function findFormType( auto )
if auto == nil or auto == '' then
return false
elseif auto == 'long' then
return true
else
return false
end
end  
-- Get the archive data and pass it to generateLinks.
local function _main( args )
local isLong = findFormType( args.auto )
local prefix = getPrefix( args.root, args.prefix, args.prefixspace )
local lineNum = getLineNum( args.links, args.nobr, isLong )
local linkPrefix = getLinkPrefix( args.linkprefix, args.linkprefixspace, isLong )
local start = getStart( args.start )
local max = getBiggestArchiveNum( prefix, start, args.max )
local sep = getSeparator( args.sep )
local lineSep = getSeparator( args.linesep )
local glargs = {
start = start,
max = max,
prefix = prefix,
linkPrefix = linkPrefix,
isLong = isLong,
sep = sep,
lineNum = lineNum,
lineSep = lineSep
}
return generateLinks( glargs )
end  
-- A wrapper function to make getBiggestArchiveNum available from
-- #invoke.
local function _count( args )