#!/usr/bin/env python

# Copyright 2018 Amazon.com, Inc. or its affiliates. All Rights Reserved.
#
# Permission is hereby granted, free of charge, to any person obtaining a copy of this
# software and associated documentation files (the "Software"), to deal in the Software
# without restriction, including without limitation the rights to use, copy, modify,
# merge, publish, distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
# INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
# PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
# HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

from geometry_msgs.msg import Twist

import rospy


class Rotator:

    def __init__(self):
        self._cmd_pub = rospy.Publisher('/cmd_vel', Twist, queue_size=1)

    def rotate_forever(self):
        self.twist = Twist()

        direction = 1
        angular_speed = 0.2
        r = rospy.Rate(0.1)
        while not rospy.is_shutdown():
            self.twist.angular.z = direction * angular_speed
            self._cmd_pub.publish(self.twist)
            rospy.loginfo('Rotating Robot: %s', self.twist)
            r.sleep()


def main():
    rospy.init_node('rotate')
    try:
        rotator = Rotator()
        rotator.rotate_forever()
    except rospy.ROSInterruptException:
        pass


if __name__ == '__main__':
    main()