View source for Module:Versions

local env = {}

local namespaces = {
	{
		-- namespace is the canonical namespace name (not an alias), e.g. the list at Special:AllPages
		namespace = '23a',
		-- versions are sorted in ascending order 
		versions = {'0.21', '0.22', '0.23'},
	},
	{
		namespace = '40d',
		versions = {'0.27', '0.28'},
	},
	{
		namespace = 'v0.31',
		versions = {'0.31'},
		aliases = {'DF2010'},
	},
	{
		namespace = 'v0.34',
		versions = {'0.34'},
		aliases = {'DF2012'},
	},
	{
		namespace = 'DF2014',
		versions = {'0.40', '0.42', '0.43', '0.44', '0.47'},
	},
	{
		namespace = 'Main',
		versions = {'50'},
		aliases = {'cv', ''},
	},
	-- mods: use the canonical name for the namespace index too, because they aren't sequenced
	Masterwork = {
		namespace = 'Masterwork',
		versions = {},
	},
}
local namespace_to_data = {}
local version_to_namespace = {}
local alias_to_namespace = {}
for i, data in pairs(namespaces) do
	if tonumber(i) ~= nil then
		data.index = i
	end
	data.canonical_version = data.versions[#data.versions]
	namespace_to_data[data.namespace] = data
	namespace_to_data[string.lower(data.namespace)] = data
	if not data.category_prefix then
		data.category_prefix = data.namespace
	end
	for _, version in pairs(data.versions or {}) do
		version_to_namespace[version] = data.namespace
	end
	for _, alias in pairs(data.aliases or {}) do
		alias_to_namespace[alias] = data.namespace
		alias_to_namespace[string.lower(alias)] = data.namespace
	end
end

function env.normalizeNamespace(ns, default)
	ns = string.lower(ns)
	ns = alias_to_namespace[ns] or ns
	ns = string.lower(ns)
	if namespace_to_data[ns] then
		return namespace_to_data[ns].namespace
	elseif default then
		return default
	else
		error('Unknown namespace: ' .. ns)
	end
end

function env.isNamespaceKnown(ns)
	if namespace_to_data[env.normalizeNamespace(ns, '')] then
		return true
	end
end

function env.isNamespaceVersioned(ns)
	if env.getIndexForNamespace(ns, '') ~= '' then
		return true
	end
end

function env.versionToNamespace(version, default)
	local parts = mw.text.split(version:gsub('^v', ''), '.', true)
	local key = ''
	while #parts > 0 do
		if key ~= '' then
			key = key .. '.'
		end
		key = key .. table.remove(parts, 1)
		if version_to_namespace[key] then
			return version_to_namespace[key]
		end
	end
	if default then
		return default
	end
	error('Unknown version: ' .. version)
end

function env.getNamespaceByIndex(i, default)
	local data = namespaces[tonumber(i)]
	if data then
		return data.namespace
	elseif default then
		return default
	else
		error('Unknown namespace index: ' .. tostring(i))
	end
end

function env.getIndexForNamespace(ns, default)
	local data = namespace_to_data[env.normalizeNamespace(ns, '')]
	if data then
		return data.index
	elseif default then
		return default
	else
		error('Unknown namespace: ' .. tostring(ns))
	end
end

function env.getIndexForVersion(v, default)
	return env.getIndexForNamespace(env.versionToNamespace(v, default), default)
end

function env.getIndexFor(key, default)
	local res = env.getIndexForNamespace(key, '')
	if res ~= '' then
		return res
	end
	return env.getIndexForVersion(key, default)
end

return env