Gearbox = class('Gearbox')

function Gearbox:initialize(config, clutch, axles)
    self.ratios = config.Ratios
    self.reverse = config.Reverse

    self.rpm = 0
    self.gear = 0
    self.torque = 0

    self.axles = axles or {}
    self.clutch = clutch

    self:recalcRatio()
end

function Gearbox:setGear(gear)
    if gear >= -1 and gear <= #self.ratios then
        self.gear = gear
        self:recalcRatio()
    end
end

function Gearbox:recalcRatio()
    if self.gear == -1 then
        self.ratio = -self.reverse
    elseif self.gear == 0 then
        self.ratio = 0
    else
        self.ratio = self.ratios[self.gear]
    end
end

function Gearbox:update()
    if self.clutch ~= nil then
        self.torque = self.clutch.torque * self.ratio
    end

    local axlesRPM = table.map(self.axles, function(diff)
        return diff.avgRPM
    end)

    local maxAxlesRPM = math.max(unpack(axlesRPM))

    self.rpm = maxAxlesRPM * self.ratio
end

function Gearbox:shift()
end