import math
from common.realtime import sec_since_boot, DT_MDL
from selfdrive.swaglog import cloudlog
from selfdrive.controls.lib.lateral_mpc import libmpc_py
from selfdrive.controls.lib.drive_helpers import MPC_COST_LAT
from selfdrive.controls.lib.lane_planner import LanePlanner
from selfdrive.config import Conversions as CV
from common.params import Params
import cereal.messaging as messaging
import cereal.messaging_arne as messaging_arne
from cereal import log
from common.op_params import opParams
from common.travis_checker import travis

LaneChangeState = log.PathPlan.LaneChangeState
LaneChangeDirection = log.PathPlan.LaneChangeDirection

LANE_CHANGE_SPEED_MIN = 20 * CV.MPH_TO_MS
LANE_CHANGE_TIME_MAX = 10.

DESIRES = {
  LaneChangeDirection.none: {
    LaneChangeState.off: log.PathPlan.Desire.none,
    LaneChangeState.preLaneChange: log.PathPlan.Desire.none,
    LaneChangeState.laneChangeStarting: log.PathPlan.Desire.none,
    LaneChangeState.laneChangeFinishing: log.PathPlan.Desire.none,
  },
  LaneChangeDirection.left: {
    LaneChangeState.off: log.PathPlan.Desire.none,
    LaneChangeState.preLaneChange: log.PathPlan.Desire.none,
    LaneChangeState.laneChangeStarting: log.PathPlan.Desire.laneChangeLeft,
    LaneChangeState.laneChangeFinishing: log.PathPlan.Desire.laneChangeLeft,
  },
  LaneChangeDirection.right: {
    LaneChangeState.off: log.PathPlan.Desire.none,
    LaneChangeState.preLaneChange: log.PathPlan.Desire.none,
    LaneChangeState.laneChangeStarting: log.PathPlan.Desire.laneChangeRight,
    LaneChangeState.laneChangeFinishing: log.PathPlan.Desire.laneChangeRight,
  },
}


def calc_states_after_delay(states, v_ego, steer_angle, curvature_factor, steer_ratio, delay):
  states[0].x = max(v_ego * delay, 0.0)
  states[0].psi = v_ego * curvature_factor * math.radians(steer_angle) / steer_ratio * delay
  return states


class PathPlanner():
  def __init__(self, CP):
    self.LP = LanePlanner()
    if not travis:
      self.arne_sm = messaging_arne.SubMaster(['arne182Status'])
      self.arne_pm = messaging_arne.PubMaster(['latControl'])
    self.last_cloudlog_t = 0
    self.steer_rate_cost = CP.steerRateCost
    self.blindspotwait = 30
    self.setup_mpc()
    self.solution_invalid_cnt = 0
    self.lane_change_enabled = Params().get('LaneChangeEnabled') == b'1'
    self.lane_change_state = LaneChangeState.off
    self.lane_change_direction = LaneChangeDirection.none
    self.lane_change_timer = 0.0
    self.lane_change_ll_prob = 1.0
    self.prev_one_blinker = False
    self.blindspotTrueCounterleft = 0
    self.blindspotTrueCounterright = 0
    self.op_params = opParams()
    self.alca_nudge_required = self.op_params.get('alca_nudge_required')
    self.alca_min_speed = self.op_params.get('alca_min_speed')

  def setup_mpc(self):
    self.libmpc = libmpc_py.libmpc
    self.libmpc.init(MPC_COST_LAT.PATH, MPC_COST_LAT.LANE, MPC_COST_LAT.HEADING, self.steer_rate_cost)

    self.mpc_solution = libmpc_py.ffi.new("log_t *")
    self.cur_state = libmpc_py.ffi.new("state_t *")
    self.cur_state[0].x = 0.0
    self.cur_state[0].y = 0.0
    self.cur_state[0].psi = 0.0
    self.cur_state[0].delta = 0.0

    self.angle_steers_des = 0.0
    self.angle_steers_des_mpc = 0.0
    self.angle_steers_des_prev = 0.0
    self.angle_steers_des_time = 0.0

  def update(self, sm, pm, CP, VM):
    if not travis:
      self.arne_sm.update(0)
      gas_button_status = self.arne_sm['arne182Status'].gasbuttonstatus
      if gas_button_status == 1:
        self.blindspotwait = 10
      elif gas_button_status == 2:
        self.blindspotwait = 30
      else:
        self.blindspotwait = 20
      if self.arne_sm['arne182Status'].rightBlindspot:
        self.blindspotTrueCounterright = 0
      else:
        self.blindspotTrueCounterright = self.blindspotTrueCounterright + 1
      if self.arne_sm['arne182Status'].leftBlindspot:
        self.blindspotTrueCounterleft = 0
      else:
        self.blindspotTrueCounterleft = self.blindspotTrueCounterleft + 1
    else:
      self.blindspotwait = 10
      self.blindspotTrueCounterleft = 0
      self.blindspotTrueCounterright = 0
    v_ego = sm['carState'].vEgo
    angle_steers = sm['carState'].steeringAngle
    active = sm['controlsState'].active

    angle_offset = sm['liveParameters'].angleOffset

    # Run MPC
    self.angle_steers_des_prev = self.angle_steers_des_mpc

    # Update vehicle model
    x = max(sm['liveParameters'].stiffnessFactor, 0.1)
    sr = max(sm['liveParameters'].steerRatio, 0.1)
    VM.update_params(x, sr)

    curvature_factor = VM.curvature_factor(v_ego)

    self.LP.parse_model(sm['model'])

    # Lane change logic
    one_blinker = sm['carState'].leftBlinker != sm['carState'].rightBlinker
    below_lane_change_speed = v_ego < self.alca_min_speed * CV.MPH_TO_MS

    if sm['carState'].leftBlinker:
      self.lane_change_direction = LaneChangeDirection.left
    elif sm['carState'].rightBlinker:
      self.lane_change_direction = LaneChangeDirection.right

    if (not active) or (self.lane_change_timer > LANE_CHANGE_TIME_MAX) or (not one_blinker) or (not self.lane_change_enabled) or (sm['carState'].steeringPressed and ((sm['carState'].steeringTorque > 0 and self.lane_change_direction == LaneChangeDirection.right) or (sm['carState'].steeringTorque < 0 and self.lane_change_direction == LaneChangeDirection.left))):
      self.lane_change_state = LaneChangeState.off
      self.lane_change_direction = LaneChangeDirection.none
    else:
      torque_applied = (sm['carState'].steeringPressed and \
                       ((sm['carState'].steeringTorque > 0 and self.lane_change_direction == LaneChangeDirection.left and not sm['carState'].leftBlindspot) or \
                        (sm['carState'].steeringTorque < 0 and self.lane_change_direction == LaneChangeDirection.right and not sm['carState'].rightBlindspot))) or \
                       (not self.alca_nudge_required and self.blindspotTrueCounterleft > self.blindspotwait and self.lane_change_direction == LaneChangeDirection.left) or \
                       (not self.alca_nudge_required and self.blindspotTrueCounterright > self.blindspotwait and self.lane_change_direction == LaneChangeDirection.right)

      #blindspot_detected = ((sm['carState'].leftBlindspot and self.lane_change_direction == LaneChangeDirection.left) or
      #                      (sm['carState'].rightBlindspot and self.lane_change_direction == LaneChangeDirection.right))

      lane_change_prob = self.LP.l_lane_change_prob + self.LP.r_lane_change_prob

      # State transitions
      # off
      if self.lane_change_state == LaneChangeState.off and one_blinker and not self.prev_one_blinker and not below_lane_change_speed:
        self.blindspotTrueCounterleft = 0
        self.blindspotTrueCounterright = 0
        self.lane_change_state = LaneChangeState.preLaneChange
        self.lane_change_ll_prob = 1.0

      # pre
      elif self.lane_change_state == LaneChangeState.preLaneChange:
        if not one_blinker or below_lane_change_speed:
          self.lane_change_state = LaneChangeState.off
          self.blindspotTrueCounterleft = 0
          self.blindspotTrueCounterright = 0
        elif torque_applied:
          self.lane_change_state = LaneChangeState.laneChangeStarting

      # starting
      elif self.lane_change_state == LaneChangeState.laneChangeStarting:
        # fade out over .5s
        self.lane_change_ll_prob = max(self.lane_change_ll_prob - 2 * DT_MDL, 0.0)
        # 98% certainty
        if lane_change_prob < 0.02 and self.lane_change_ll_prob < 0.01:
          self.lane_change_state = LaneChangeState.laneChangeFinishing
        if (self.arne_sm['arne182Status'].rightBlindspot and self.lane_change_direction == LaneChangeDirection.right) or (self.arne_sm['arne182Status'].leftBlindspot and self.lane_change_direction == LaneChangeDirection.left):
          self.lane_change_state = LaneChangeState.preLaneChange
          self.blindspotTrueCounterleft = 0
          self.blindspotTrueCounterright = 0


      # finishing
      elif self.lane_change_state == LaneChangeState.laneChangeFinishing:
        # fade in laneline over 1s
        self.lane_change_ll_prob = min(self.lane_change_ll_prob + DT_MDL, 1.0)
        if one_blinker and self.lane_change_ll_prob > 0.99:
          self.lane_change_state = LaneChangeState.preLaneChange
          self.blindspotTrueCounterleft = 0
          self.blindspotTrueCounterright = 0
        elif self.lane_change_ll_prob > 0.99:
          self.lane_change_state = LaneChangeState.off
          self.blindspotTrueCounterright = 0
          self.blindspotTrueCounterleft = 0

    if self.lane_change_state in [LaneChangeState.off, LaneChangeState.preLaneChange]:
      self.lane_change_timer = 0.0
    else:
      self.lane_change_timer += DT_MDL

    self.prev_one_blinker = one_blinker

    desire = DESIRES[self.lane_change_direction][self.lane_change_state]

    # Turn off lanes during lane change
    if desire == log.PathPlan.Desire.laneChangeRight or desire == log.PathPlan.Desire.laneChangeLeft:
      self.LP.l_prob *= self.lane_change_ll_prob
      self.LP.r_prob *= self.lane_change_ll_prob

    self.LP.update_d_poly(v_ego)

    # account for actuation delay
    self.cur_state = calc_states_after_delay(self.cur_state, v_ego, angle_steers - angle_offset, curvature_factor, VM.sR, self.op_params.get('steer_actuator_delay'))

    #if abs(angle_steers - angle_offset) > 4 and CP.lateralTuning.which() == 'pid': #check if this causes laggy steering
    #  self.cur_state[0].delta = math.radians(angle_steers - angle_offset) / VM.sR

    v_ego_mpc = max(v_ego, 5.0)  # avoid mpc roughness due to low speed
    self.libmpc.run_mpc(self.cur_state, self.mpc_solution,
                        list(self.LP.l_poly), list(self.LP.r_poly), list(self.LP.d_poly),
                        self.LP.l_prob, self.LP.r_prob, curvature_factor, v_ego_mpc, self.LP.lane_width)

    # reset to current steer angle if not active or overriding
    if active:
      delta_desired = self.mpc_solution[0].delta[1]
      rate_desired = math.degrees(self.mpc_solution[0].rate[0] * VM.sR)
    else:
      delta_desired = math.radians(angle_steers - angle_offset) / VM.sR
      rate_desired = 0.0

    self.cur_state[0].delta = delta_desired

    self.angle_steers_des_mpc = float(math.degrees(delta_desired * VM.sR) + angle_offset)

    #  Check for infeasable MPC solution
    mpc_nans = any(math.isnan(x) for x in self.mpc_solution[0].delta)
    t = sec_since_boot()
    if mpc_nans:
      self.libmpc.init(MPC_COST_LAT.PATH, MPC_COST_LAT.LANE, MPC_COST_LAT.HEADING, CP.steerRateCost)
      self.cur_state[0].delta = math.radians(angle_steers - angle_offset) / VM.sR

      if t > self.last_cloudlog_t + 5.0:
        self.last_cloudlog_t = t
        cloudlog.warning("Lateral mpc - nan: True")

    if self.mpc_solution[0].cost > 20000. or mpc_nans:   # TODO: find a better way to detect when MPC did not converge
      self.solution_invalid_cnt += 1
    else:
      self.solution_invalid_cnt = 0
    plan_solution_valid = self.solution_invalid_cnt < 2

    plan_send = messaging.new_message('pathPlan')
    plan_send.valid = sm.all_alive_and_valid(service_list=['carState', 'controlsState', 'liveParameters', 'model'])
    plan_send.pathPlan.laneWidth = float(self.LP.lane_width)
    plan_send.pathPlan.dPoly = [float(x) for x in self.LP.d_poly]
    plan_send.pathPlan.lPoly = [float(x) for x in self.LP.l_poly]
    plan_send.pathPlan.lProb = float(self.LP.l_prob)
    plan_send.pathPlan.rPoly = [float(x) for x in self.LP.r_poly]
    plan_send.pathPlan.rProb = float(self.LP.r_prob)

    plan_send.pathPlan.angleSteers = float(self.angle_steers_des_mpc)
    plan_send.pathPlan.rateSteers = float(rate_desired)
    plan_send.pathPlan.angleOffset = float(sm['liveParameters'].angleOffsetAverage)
    plan_send.pathPlan.mpcSolutionValid = bool(plan_solution_valid)
    plan_send.pathPlan.paramsValid = bool(sm['liveParameters'].valid)

    plan_send.pathPlan.desire = desire
    plan_send.pathPlan.laneChangeState = self.lane_change_state
    plan_send.pathPlan.laneChangeDirection = self.lane_change_direction

    pm.send('pathPlan', plan_send)

    dat = messaging.new_message('liveMpc')
    dat.liveMpc.x = list(self.mpc_solution[0].x)
    dat.liveMpc.y = list(self.mpc_solution[0].y)
    dat.liveMpc.psi = list(self.mpc_solution[0].psi)
    dat.liveMpc.delta = list(self.mpc_solution[0].delta)
    dat.liveMpc.cost = self.mpc_solution[0].cost
    pm.send('liveMpc', dat)

    msg = messaging_arne.new_message('latControl')
    msg.latControl.anglelater = math.degrees(list(self.mpc_solution[0].delta)[-1])
    if not travis:
      self.arne_pm.send('latControl', msg)
