text: #!/usr/bin/env python
  from common.realtime import sec_since_boot
  from cereal import car
  from selfdrive.config import Conversions as CV
  from selfdrive.controls.lib.drive_helpers import EventTypes as ET, create_event
  from selfdrive.controls.lib.vehicle_model import VehicleModel
  from selfdrive.car.ford.carstate import CarState, get_can_parser
  from selfdrive.car.ford.fordcan import MAX_ANGLE
  
  try:
    from selfdrive.car.ford.carcontroller import CarController
  except ImportError:
    CarController = None
  
  
  class CarInterface(object):
    def __init__(self, CP, sendcan=None):
      self.CP = CP
      self.VM = VehicleModel(CP)
  
      self.frame = 0
      self.can_invalid_count = 0
      self.gas_pressed_prev = False
      self.brake_pressed_prev = False
      self.cruise_enabled_prev = False
  
      # *** init the major players ***
      self.CS = CarState(CP)
  
      self.cp = get_can_parser(CP)
  
      # sending if read only is False
      if sendcan is not None:
        self.sendcan = sendcan
        self.CC = CarController(self.cp.dbc_name, CP.enableCamera, self.VM)
  
    @staticmethod
    def compute_gb(accel, speed):
      return float(accel) / 3.0
  
    @staticmethod
    def calc_accel_override(a_ego, a_target, v_ego, v_target):
      return 1.0
  
    @staticmethod
    def get_params(candidate, fingerprint):
  
      # kg of standard extra cargo to count for drive, gas, etc...
      std_cargo = 136
  
      ret = car.CarParams.new_message()
  
      ret.carName = "ford"
      ret.carFingerprint = candidate
  
      ret.safetyModel = car.CarParams.SafetyModels.ford
  
      # pedal
      ret.enableCruise = True
  
      # FIXME: hardcoding honda civic 2016 touring params so they can be used to
      # scale unknown params for other cars
      mass_civic = 2923./2.205 + std_cargo
      wheelbase_civic = 2.70
      centerToFront_civic = wheelbase_civic * 0.4
      centerToRear_civic = wheelbase_civic - centerToFront_civic
      rotationalInertia_civic = 2500
      tireStiffnessFront_civic = 85400
      tireStiffnessRear_civic = 90000
  
      ret.steerKiBP, ret.steerKpBP = [[0.], [0.]]
      ret.wheelbase = 2.85
      ret.steerRatio = 14.8
      ret.mass = 3045./2.205 + std_cargo
      ret.steerKpV, ret.steerKiV = [[0.01], [0.005]]     # TODO: tune this
      ret.steerKf = 1. / MAX_ANGLE   # MAX Steer angle to normalize FF
      ret.steerActuatorDelay = 0.1  # Default delay, not measured yet
  
      f = 1.2
      tireStiffnessFront_civic *= f
      tireStiffnessRear_civic *= f
  
      ret.centerToFront = ret.wheelbase * 0.44
  
      ret.longPidDeadzoneBP = [0., 9.]
      ret.longPidDeadzoneV = [0., .15]
  
      # min speed to enable ACC. if car can do stop and go, then set enabling speed
      # to a negative value, so it won't matter.
      ret.minEnableSpeed = -1.
  
      centerToRear = ret.wheelbase - ret.centerToFront
      # TODO: get actual value, for now starting with reasonable value for
      # civic and scaling by mass and wheelbase
      ret.rotationalInertia = rotationalInertia_civic * \
                              ret.mass * ret.wheelbase**2 / (mass_civic * wheelbase_civic**2)
  
      # TODO: start from empirically derived lateral slip stiffness for the civic and scale by
      # mass and CG position, so all cars will have approximately similar dyn behaviors
      ret.tireStiffnessFront = tireStiffnessFront_civic * \
                               ret.mass / mass_civic * \
                               (centerToRear / ret.wheelbase) / (centerToRear_civic / wheelbase_civic)
      ret.tireStiffnessRear = tireStiffnessRear_civic * \
                              ret.mass / mass_civic * \
                              (ret.centerToFront / ret.wheelbase) / (centerToFront_civic / wheelbase_civic)
  
      # no rear steering, at least on the listed cars above
      ret.steerRatioRear = 0.
      ret.steerControlType = car.CarParams.SteerControlType.angle
  
      # steer, gas, brake limitations VS speed
      ret.steerMaxBP = [0.]  # breakpoints at 1 and 40 kph
      ret.steerMaxV = [1.0]  # 2/3rd torque allowed above 45 kph
      ret.gasMaxBP = [0.]
      ret.gasMaxV = [0.5]
      ret.brakeMaxBP = [5., 20.]
      ret.brakeMaxV = [1., 0.8]
  
      ret.enableCamera = not any(x for x in [970, 973, 984] if x in fingerprint)
      print "ECU Camera Simulated: ", ret.enableCamera
  
      ret.steerLimitAlert = False
      ret.stoppingControl = False
      ret.startAccel = 0.0
  
      ret.longitudinalKpBP = [0., 5., 35.]
      ret.longitudinalKpV = [3.6, 2.4, 1.5]
      ret.longitudinalKiBP = [0., 35.]
      ret.longitudinalKiV = [0.54, 0.36]
  
      return ret
  
    # returns a car.CarState
    def update(self, c):
      # ******************* do can recv *******************
      canMonoTimes = []
  
      self.cp.update(int(sec_since_boot() * 1e9), False)
  
      self.CS.update(self.cp)
  
      # create message
      ret = car.CarState.new_message()
  
      # speeds
      ret.vEgo = self.CS.v_ego
      ret.vEgoRaw = self.CS.v_ego_raw
      ret.standstill = self.CS.standstill
      ret.wheelSpeeds.fl = self.CS.v_wheel_fl
      ret.wheelSpeeds.fr = self.CS.v_wheel_fr
      ret.wheelSpeeds.rl = self.CS.v_wheel_rl
      ret.wheelSpeeds.rr = self.CS.v_wheel_rr
  
      # steering wheel
      ret.steeringAngle = self.CS.angle_steers
      ret.steeringPressed = self.CS.steer_override
  
      # gas pedal
      ret.gas = self.CS.user_gas / 100.
      ret.gasPressed = self.CS.user_gas > 0.0001
      ret.brakePressed = self.CS.brake_pressed
      ret.brakeLights = self.CS.brake_lights
  
      ret.cruiseState.enabled = not (self.CS.pcm_acc_status in [0, 3])
      ret.cruiseState.speed = self.CS.v_cruise_pcm
      ret.cruiseState.available = self.CS.pcm_acc_status != 0
  
      ret.genericToggle = self.CS.generic_toggle
  
      # events
      events = []
      if not self.CS.can_valid:
        self.can_invalid_count += 1
        if self.can_invalid_count >= 5:
          events.append(create_event('commIssue', [ET.NO_ENTRY, ET.IMMEDIATE_DISABLE]))
      else:
        self.can_invalid_count = 0
  
      if self.CS.steer_error:
        events.append(create_event('steerUnavailable', [ET.NO_ENTRY, ET.IMMEDIATE_DISABLE, ET.PERMANENT]))
  
      # enable request in prius is simple, as we activate when Toyota is active (rising edge)
      if ret.cruiseState.enabled and not self.cruise_enabled_prev:
        events.append(create_event('pcmEnable', [ET.ENABLE]))
      elif not ret.cruiseState.enabled:
        events.append(create_event('pcmDisable', [ET.USER_DISABLE]))
  
      # disable on pedals rising edge or when brake is pressed and speed isn't zero
      if (ret.gasPressed and not self.gas_pressed_prev) or \
         (ret.brakePressed and (not self.brake_pressed_prev or ret.vEgo > 0.001)):
        events.append(create_event('pedalPressed', [ET.NO_ENTRY, ET.USER_DISABLE]))
  
      if ret.gasPressed:
        events.append(create_event('pedalPressed', [ET.PRE_ENABLE]))
  
      if self.CS.lkas_state not in [2, 3] and ret.vEgo > 13.* CV.MPH_TO_MS and ret.cruiseState.enabled:
        events.append(create_event('steerTempUnavailableMute', [ET.WARNING]))
  
      ret.events = events
      ret.canMonoTimes = canMonoTimes
  
      self.gas_pressed_prev = ret.gasPressed
      self.brake_pressed_prev = ret.brakePressed
      self.cruise_enabled_prev = ret.cruiseState.enabled
  
      return ret.as_reader()
  
    # pass in a car.CarControl
    # to be called @ 100hz
    def apply(self, c):
  
      self.CC.update(self.sendcan, c.enabled, self.CS, self.frame, c.actuators,
                     c.hudControl.visualAlert, c.cruiseControl.cancel)
  
      self.frame += 1
      return False
  