-- @include ./wire_component.txt
-- @include /koptilnya/libs/constants.txt
require('./wire_component.txt')
require('/koptilnya/libs/constants.txt')

Engine = class('Engine', WireComponent)

function Engine:initialize(config, clutch)
    self.idleRPM = config.IdleRPM
    self.maxRPM = config.MaxRPM

    self.flywheelMass = config.FlywheelMass
    self.flywheelRadius = config.FlywheelRadius

    self.startFriction = config.StartFriction
    self.frictionCoeff = config.FrictionCoeff

    self.torque = 0
    self.rpmFrac = 0
    self.rpm = self.idleRPM
    self.friction = 0

    self.limiterDuration = config.LimiterDuration

    self.torqueMap = config.TorqueMap or {}

    self._fwInertia = self.flywheelMass * self.flywheelRadius ^ 2 / 2
    self._limiterTime = 0

    self._clutch = clutch
end

function Engine:getInputs()
    return {
        Throttle = 'number'
    }
end

function Engine:getOutputs()
    return {
        RPM = 'number',
        Torque = 'number'
    }
end

function Engine:updateOutputs()
    wire.ports.RPM = self.rpm
    wire.ports.Torque = self.torque
end

function Engine:getThrottle()
    return wire.ports.Throttle
end

function Engine:update()
    local throttle = self:getThrottle()

    self.rpmFrac = math.clamp((self.rpm - self.idleRPM) / (self.maxRPM - self.idleRPM), 0, 1)
    self.friction = self.startFriction - self.rpm * self.frictionCoeff

    local tqIdx = math.clamp(math.floor(self.rpmFrac * #self.torqueMap), 1, #self.torqueMap)
    local maxInitialTorque = self.torqueMap[tqIdx] - self.friction

    local idleFadeStart = math.clamp(math.remap(self.rpm, self.idleRPM - 300, self.idleRPM, 1, 0), 0, 1)
    local idleFadeEnd = math.clamp(math.remap(self.rpm, self.idleRPM, self.idleRPM + 600, 1, 0), 0, 1)

    local additionalEnergySupply = idleFadeEnd * (-self.friction / maxInitialTorque) + idleFadeStart

    if self.rpm > self.maxRPM then
        throttle = 0
        self._limiterTime = timer.systime()
    else
        throttle = timer.systime() >= self._limiterTime + self.limiterDuration and throttle or 0
    end

    local masterThrottle = math.clamp(additionalEnergySupply + throttle, 0, 1)

    local realInitialTorque = maxInitialTorque * masterThrottle

    local loadTorque = self._clutch and self._clutch.torque or 0

    self.torque = realInitialTorque + self.friction

    self.rpm = self.rpm + (self.torque - loadTorque) / self._fwInertia * RAD_TO_RPM * TICK_INTERVAL
    self.rpm = math.max(self.rpm, 0)
end