kingdoms_game/mods/utils/settings.lua

--[[
Copyright (c) 2015, Robert 'Bobby' Zenz
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OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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--]]


--- Encapsulates the settings API of minetest and extends it with further
-- functions.
settings = {}


--- Gets a value from the configuration as is.
--
-- @param name The name of the value to get.
-- @param default_value Optional. The default_value to return if the value is
--                      not set in the configuration. Can be nil.
-- @param cast_function Optional. The function to apply to the value that is
--                      read, for example to convert it into a different type.
--                      If this function returns nil, the default value IS
--                      returned. Can be nil.
-- @return The value from the configuration with the given name. If the read
--         value is nil, the default value is returned or nil.
function settings.get(name, default_value, cast_function)
	local value = minetest.settings:get(name)

	if value ~= nil and cast_function ~= nil then
		value = cast_function(value)
	end

	if value ~= nil then
		return value
	else
		return default_value
	end
end

--- Gets a boolean from the configuration.
--
-- @param name The name of the value to get.
-- @param default_value Optional. The default value to return if the value is nil.
--                      Can be nil.
-- @return The boolean with the given name, or the default value if it is nil,
--         or nil.
function settings.get_bool(name, default_value)
	local value = minetest.settings:get_bool(name)

	if value ~= nil then
		return value
	else
		return default_value
	end
end

--- Gets a list from the configuration.
--
-- @param name The name of the value to get.
-- @param default_value Optional. The default value to return if the value is
--                      nil. Can be nil.
-- @return The list with the given name, or the default value if it is nil,
--        or nil.
function settings.get_list(name, default_value)
	local value = settings.get(name, nil, tostring)

	if value ~= nil then
		return stringutil.split(value, ",")
	elseif type(default_value) == "string" then
		return stringutil.split(default_value, ",")
	else
		return default_value
	end
end

--- Gets a number from the configuration.
--
-- @param name The name of the value to get.
-- @param default_value Optional. The default value to return if the value is nil.
--                      Can be nil.
-- @return The number with the given name, or the default value if it is nil,
--         or nil.
function settings.get_number(name, default_value)
	return settings.get(name, default_value, tonumber)
end

--- Gets a pos (with x and y values) from the configuration.
--
-- @param name The name of the value to get.
-- @param default_value Optional. The default value to return if the value is nil.
--                      Can be nil.
-- @return The pos with the given name, or the default value if it is nil,
--         or nil.
function settings.get_pos2d(name, default_value)
	local value = minetest.settings:get(name)
	if value ~= nil then
		local splitted_value = stringutil.split(value, ",")

		if splitted_value:size() == 2 then
			local x = tonumber(splitted_value:get(1))
			local y = tonumber(splitted_value:get(2))

			if x ~= nil and y ~= nil then
				return {
					x = x,
					y = y
				}
			end
		end
	end

	return default_value
end

--- Gets a pos with (x, y and z values) from the configuration.
--
-- @param name The name of the value to get.
-- @param default_value Optional. The default value to return if the value is nil.
--                      Can be nil.
-- @return The pos with the given name, or the default value if it is nil,
--         or nil.
function settings.get_pos3d(name, default_value)
	local value = minetest.setting_get_pos(name)

	if value ~= nil then
		return value
	else
		return default_value
	end
end

--- Gets a string from the configuration.
--
-- @param name The name of the value to get.
-- @param default_value Optional. The default value to return if the value is nil.
--                      Can be nil.
-- @return The string with the given name, or the default value if it is nil,
--         or nil.
function settings.get_string(name, default_value)
	return settings.get(name, default_value, tostring)
end

--- Gets a table with the given keys form the configuration.
--
-- @param name The name of the value to get.
-- @param default_value The default value to return if the value is nil, can be
--                      nil.
-- @param ... The name of the keys.
-- @return The table with the given name and the given keys, or the default
--         value it is nil.
function settings.get_table(name, default_value, ...)
	local value = settings.get_list(name, nil)

	if value ~= nil then
		local table = {}

		if ... ~= nil then
			for index, key in ipairs({...}) do
				table[key] = value:get(index)
			end
		end

		if ... == nil or  #{...} < value:size() then
			for index = #{...} + 1, value:size(), 1 do
				table[index] = value:get(index)
			end
		end

		return table
	else
		return default_value
	end
end

--- Saves all settings to configuration file.
function settings.save()
	minetest.settings:write()
end

--- Set a value with the given name into the configuration.
--
-- @param name The name of the value to set. Is not allowed to contain '="#{}'.
-- @param value The value.
function settings.set(name, value)
	minetest.settings:set(name, value)
end

--- Gets a pos from the configuration, this is an alias for get_pos3d.
--
-- @param name The name of the value to get.
-- @param default_value Optional. The default value to return if the value is nil.
--                      Can be nil.
-- @return The pos with the given name, or the default value if it is nil,
--         or nil.
settings.get_pos = settings.get_pos3d