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#!/usr/bin/env python

import roslib
import rospy
import serial
from math import pi
import math
import tf
import time
import geometry_msgs
import nav_msgs
from nav_msgs.msg import Odometry
from geometry_msgs.msg import Twist


odom_frame = "odom"
base_frame = "base_link"
lin_x = 0.0
ang_z = 0.0



def get_vel(data):
	global lin_x
	global ang_z
	lin_x = data.linear.x
	ang_z = data.angular.z


if __name__=='__main__':
	try:
		rospy.init_node('odom_send')

                odom_pub = rospy.Publisher('odom', Odometry, queue_size = 50)
		rospy.loginfo("Starting odom node")

		tf_listener = tf.TransformListener()

		odom = nav_msgs.msg.Odometry()
                current_time = rospy.Time.now()

		odom.header.frame_id = odom_frame
		odom.child_frame_id = base_frame

		rospy.Subscriber("turtle1/cmd_vel", Twist, get_vel)

		rate = rospy.get_param('~rate', 20)
		r = rospy.Rate(rate)
		while not rospy.is_shutdown():
			try:
		       		current_time = rospy.Time.now()
				trans,rot = tf_listener.lookupTransform(odom_frame, base_frame, rospy.Time()  )
				odom.header.stamp = current_time
				odom.pose.pose.position.x = trans[0]
				print trans[0]
				odom.pose.pose.position.y = trans[1]
				odom.pose.pose.position.z = 0.0
				print rot
				odom.pose.pose.orientation.x = rot[0]
				odom.pose.pose.orientation.y = rot[1]
				odom.pose.pose.orientation.z = rot[2]
				odom.pose.pose.orientation.w = rot[3]

				odom.twist.twist.linear.x = lin_x
				print lin_x
				odom.twist.twist.linear.y = 0.0
				odom.twist.twist.linear.z = 0.0
	  			odom.twist.twist.angular.x = 0.0
	  			odom.twist.twist.angular.y = 0.0
	  			odom.twist.twist.angular.z = ang_z
				print ang_z
				#print odom

				odom_pub.publish(odom)
				rospy.loginfo("Public!")
				r.sleep()
			except (tf.LookupException, tf.ConnectivityException, tf.ExtrapolationException):
				continue

	except rospy.ROSInterruptException as e:
		print e