Module:Daily

Documentation for this module may be created at Module:Daily/doc

-- Picks one line of a list page per day, the same line for every visitor.
-- {{#invoke:Daily|pick|list=Template:Did you know/list}} returns the whole line;
-- add |field=2 to return the second part of a line split on "|".
local p = {}

local SECONDS_PER_DAY = 86400

local function readList( listTitle )
	local title = mw.title.new( listTitle )
	local text = title and title:getContent() or ''
	local entries = {}
	for line in mw.text.gsplit( text, '\n', true ) do
		line = mw.text.trim( ( line:gsub( '^%*+', '' ) ) )
		if line ~= '' then
			entries[ #entries + 1 ] = line
		end
	end
	return entries
end

function p.pick( frame )
	local args = frame.args
	local entries = readList( args.list or '' )
	if #entries == 0 then
		return ''
	end
	local day = math.floor( tonumber( mw.getContentLanguage():formatDate( 'U' ) ) / SECONDS_PER_DAY )
	local entry = entries[ ( day + ( tonumber( args.offset ) or 0 ) ) % #entries + 1 ]
	local field = tonumber( args.field )
	if field then
		entry = mw.text.trim( mw.text.split( entry, '|', true )[ field ] or '' )
	end
	return frame:preprocess( entry )
end

return p