Module:Infobox film/track

local p = {}

local function check(args, sources, targets)
	local source
	for _, param in ipairs(sources) do
		if args[param] and args[param] ~= '' then
			source = param
			break
		end
	end
	if not source then
		return nil
	end
	local warnings = {}
	for link in mw.ustring.gmatch(args[source], '%[%[[^%[%]]+%]%]') do
		local name = mw.ustring.match(link, '([^%|]+)%]%]$', 3)
		for _, param in ipairs(targets) do
			if args[param] and args[param] ~= '' then
				local match = mw.ustring.match(args[param], '.?.?%f[%w]' .. name .. '%f[%W]')
				-- Eliminate duplicate links
				if match and not mw.ustring.find(match, '^%[[%[:]') then
					table.insert(warnings, 'The link <code>' .. mw.text.nowiki(link) .. '</code> in <code>|' .. source .. '=</code> should be moved to <code>|' .. param .. '=</code>.')
					break
				end
			end
		end
	end
	return warnings
end

function p.main(frame)
	local args = frame:getParent().args
	local warnings = check(args, {'producer', 'producers'}, {'writer', 'writers', 'screenplay', 'story', 'based_on'}) or {}
	local warnings2 = check(args, {'music'}, {'cinematography', 'editing'}) or {}
	for _, v in ipairs(warnings2) do
		table.insert(warnings, v)
	end
	if #warnings ~= 0 then
		local ret = require('Module:If preview')._warning({table.concat(warnings, ' ')})
		local namespace = mw.title.getCurrentTitle().namespace
		if namespace == 0 or namespace == 118 then
			ret = ret .. '[[Category:Pages using infobox film with incorrectly placed links]]'
		end
		return ret
	end
end

return p