#!/usr/bin/env python
import zmq
from cereal import car
from selfdrive.config import Conversions as CV
from selfdrive.services import service_list
import selfdrive.messaging as messaging

# mocked car interface to work with chffrplus
TS = 0.01  # 100Hz
YAW_FR = 0.2 # ~0.8s time constant on yaw rate filter
# low pass gain
LPG = 2 * 3.1415 * YAW_FR * TS / (1 + 2 * 3.1415 * YAW_FR * TS)


class CarInterface(object):
  def __init__(self, CP, sendcan=None):

    self.CP = CP

    print "Using Mock Car Interface"
    context = zmq.Context()

    # TODO: subscribe to phone sensor
    self.sensor = messaging.sub_sock(context, service_list['sensorEvents'].port)
    self.gps = messaging.sub_sock(context, service_list['gpsLocation'].port)

    self.speed = 0.
    self.yaw_rate = 0.
    self.yaw_rate_meas = 0.

  @staticmethod
  def compute_gb(accel, speed):
    return accel

  @staticmethod
  def calc_accel_override(a_ego, a_target, v_ego, v_target):
    return 1.0

  @staticmethod
  def get_params(candidate, fingerprint):

    ret = car.CarParams.new_message()

    ret.carName = "mock"
    ret.carFingerprint = candidate

    ret.safetyModel = car.CarParams.SafetyModels.noOutput

    # FIXME: hardcoding honda civic 2016 touring params so they can be used to
    # scale unknown params for other cars
    ret.mass = 1700.
    ret.rotationalInertia = 2500.
    ret.wheelbase = 2.70
    ret.centerToFront = ret.wheelbase * 0.5
    ret.steerRatio = 13. # reasonable
    ret.longPidDeadzoneBP = [0.]
    ret.longPidDeadzoneV = [0.]
    ret.tireStiffnessFront = 1e6    # very stiff to neglect slip
    ret.tireStiffnessRear = 1e6     # very stiff to neglect slip
    ret.steerRatioRear = 0.

    ret.steerMaxBP = [0.]
    ret.steerMaxV = [0.]  # 2/3rd torque allowed above 45 kph
    ret.gasMaxBP = [0.]
    ret.gasMaxV = [0.]
    ret.brakeMaxBP = [0.]
    ret.brakeMaxV = [0.]

    ret.longitudinalKpBP = [0.]
    ret.longitudinalKpV = [0.]
    ret.longitudinalKiBP = [0.]
    ret.longitudinalKiV = [0.]

    return ret

  # returns a car.CarState
  def update(self, c):

    # get basic data from phone and gps since CAN isn't connected
    sensors = messaging.recv_sock(self.sensor)
    if sensors is not None:
      for sensor in sensors.sensorEvents:
        if sensor.type == 4:  # gyro
          self.yaw_rate_meas = -sensor.gyro.v[0]

    gps = messaging.recv_sock(self.gps)
    if gps is not None:
      self.speed = gps.gpsLocation.speed

    # create message
    ret = car.CarState.new_message()

    # speeds
    ret.vEgo = self.speed
    ret.vEgoRaw = self.speed
    ret.aEgo = 0.
    self.yawRate = LPG * self.yaw_rate_meas + (1. - LPG) * self.yaw_rate
    ret.yawRate = self.yaw_rate
    ret.standstill = self.speed < 0.01
    ret.wheelSpeeds.fl = self.speed
    ret.wheelSpeeds.fr = self.speed
    ret.wheelSpeeds.rl = self.speed
    ret.wheelSpeeds.rr = self.speed
    curvature = self.yaw_rate / max(self.speed, 1.)
    ret.steeringAngle = curvature * self.CP.steerRatio * self.CP.wheelbase * CV.RAD_TO_DEG

    events = []
    ret.events = events

    return ret.as_reader()

  def apply(self, c):
    # in mock no carcontrols
    return False