#!/usr/bin/env python

import rospy
from geometry_msgs.msg import PoseStamped
from styx_msgs.msg import Lane, Waypoint

import tf
from std_msgs.msg import Int32, Bool
import math
import numpy as np

'''
This node will publish waypoints from the car's current position to some `x` distance ahead.

As mentioned in the doc, you should ideally first implement a version which does not care
about traffic lights or obstacles.

Once you have created dbw_node, you will update this node to use the status of traffic lights too.

Please note that our simulator also provides the exact location of traffic lights and their
current status in `/vehicle/traffic_lights` message. You can use this message to build this node
as well as to verify your TL classifier.

TODO (for Yousuf and Aaron): Stopline location for each traffic light.
'''

LOOKAHEAD_WPS = 200 # Number of waypoints we will publish. You can change this number


class WaypointUpdater(object):
    def __init__(self):
        rospy.init_node('waypoint_updater')

        rospy.Subscriber('/current_pose', PoseStamped, self.pose_cb)
        rospy.Subscriber('/base_waypoints', Lane, self.waypoints_cb)

        # TODO: Add a subscriber for /traffic_waypoint and /obstacle_waypoint below


        self.final_waypoints_pub = rospy.Publisher('final_waypoints', Lane, queue_size=1)

        # TODO: Add other member variables you need below
        # self.final_waypoints_pub = rospy.Publisher('final_waypoints', Lane, queue_size=1)

        self.pose = None
        self.base_waypoints = None
        self.waypoints_2d = None
        self.waypoint_tree = None

        self.loop()

    def loop(self):
        rate = rospy.Rate(50)
        #time.sleep(3000)
        while not rospy.is_shutdown():
            #rospy.loginfo('inside self.loop')
            #rospy.loginfo(self.pose)
            if self.pose and self.base_waypoints :
                rospy.loginfo('inside self.loop')
                closest_waypoint_idx = self.get_closest_waypoint_id()
                self.publish_waypoints(closest_waypoint_idx)
            rate.sleep()

    def get_closest_waypoint_id(self):
        x = self.pose.pose.position.x
        y = self.pose.pose.position.y
        rospy.loginfo('get closest waypoint')
        closest_idx = self.waypoint_tree.query([x,y],1)[1]
        rospy.loginfo(closest_idx)

        # check closest is ahead or behind the car
        closest_coord = self.waypoints_2d[closest_idx]
        prev_coord = self.waypoints_2d[closest_idx - 1]

        # Equation for hyperplane through closest_coords
        cl_vect = np.array(closest_coord)
        prev_vect= np.array(prev_coord)
        pos_vect = np.array([x,y])

        val = np.dot(cl_vect-prev_vect,pos_vect-cl_vect)

        if val>0:
            closest_idx = (closest_idx+1)%len(self.waypoints_2d)
        
        return closest_idx

    def publish_waypoints(self,closest_idx):
        lane = Lane()
        rospy.loginfo('inside publish waypoints')
        lane.header = self.base_waypoints.header
        rospy.loginfo(' header set')
        lane.waypoints = self.base_waypoints.waypoints[closest_idx : closest_idx + LOOKAHEAD_WPS]
        rospy.loginfo(' waypoints set, size :')
        rospy.loginfo( len(lane.waypoints))
        self.final_waypoints_pub.publish(lane)
        rospy.loginfo(' published')

    def pose_cb(self, msg):
        self.pose = msg

    def waypoints_cb(self, waypoints):
        rospy.loginfo('In funnction waypoints_cb')  
        self.base_waypoints = waypoints
        if not self.waypoints_2d:
            rospy.loginfo('setting kd tree ')
            self.waypoints_2d = [[waypoint.pose.pose.position.x,waypoint.pose.pose.position.y] for waypoint in waypoints.waypoints]
            #rospy.loginfo(self.waypoints_2d)
            self.waypoint_tree = KDTree(self.waypoints_2d)
            rospy.loginfo(len(self.waypoint_tree.data))

    def traffic_cb(self, msg):
        # TODO: Callback for /traffic_waypoint message. Implement
        pass

    def obstacle_cb(self, msg):
        # TODO: Callback for /obstacle_waypoint message. We will implement it later
        pass

    def get_waypoint_velocity(self, waypoint):
        return waypoint.twist.twist.linear.x

    def set_waypoint_velocity(self, waypoints, waypoint, velocity):
        waypoints[waypoint].twist.twist.linear.x = velocity

    def distance(self, waypoints, wp1, wp2):
        dist = 0
        dl = lambda a, b: math.sqrt((a.x-b.x)**2 + (a.y-b.y)**2  + (a.z-b.z)**2)
        for i in range(wp1, wp2+1):
            dist += dl(waypoints[wp1].pose.pose.position, waypoints[i].pose.pose.position)
            wp1 = i
        return dist


if __name__ == '__main__':
    try:
        WaypointUpdater()
    except rospy.ROSInterruptException:
        rospy.logerr('Could not start waypoint updater node.')

numpy.array numpy.dot