#!/usr/bin/env python

# Copyright (c) 2011, Willow Garage, Inc.
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
#    * Redistributions of source code must retain the above copyright
#      notice, this list of conditions and the following disclaimer.
#    * Redistributions in binary form must reproduce the above copyright
#      notice, this list of conditions and the following disclaimer in the
#      documentation and/or other materials provided with the distribution.
#    * Neither the name of the Willow Garage, Inc. nor the names of its
#      contributors may be used to endorse or promote products derived from
#       this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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# POSSIBILITY OF SUCH DAMAGE.

import roslib; roslib.load_manifest('turtlebot_teleop')
import rospy

from geometry_msgs.msg import Twist

import sys, select, termios, tty

msg = """
Control Your TurtleBot!
---------------------------
Moving around:
   u    i    o
   j    k    l
   m    ,    .

q/z : increase/decrease max speeds by 10%
w/x : increase/decrease only linear speed by 10%
e/c : increase/decrease only angular speed by 10%
anything else : stop

CTRL-C to quit
"""

moveBindings = {
        'i':(1,0),
        'o':(1,-1),
        'j':(0,1),
        'l':(0,-1),
        'u':(1,1),
        ',':(-1,0),
        '.':(-1,1),
        'm':(-1,-1),
           }

speedBindings={
        'q':(1.1,1.1),
        'z':(.9,.9),
        'w':(1.1,1),
        'x':(.9,1),
        'e':(1,1.1),
        'c':(1,.9),
          }

def getKey():
    tty.setraw(sys.stdin.fileno())
    select.select([sys.stdin], [], [], 0)
    key = sys.stdin.read(1)
    termios.tcsetattr(sys.stdin, termios.TCSADRAIN, settings)
    return key

speed = .3
turn = 1

def vels(speed,turn):
    return "currently:\tspeed %s\tturn %s " % (speed,turn)

if __name__=="__main__":
    settings = termios.tcgetattr(sys.stdin)
    
    pub = rospy.Publisher('cmd_vel', Twist)
    rospy.init_node('turtlebot_teleop')

    x = 0
    th = 0
    status = 0

    try:
        print msg
        print vels(speed,turn)
        while(1):
            key = getKey()
            if key in moveBindings.keys():
                x = moveBindings[key][0]
                th = moveBindings[key][1]
            elif key in speedBindings.keys():
                speed = speed * speedBindings[key][0]
                turn = turn * speedBindings[key][1]

                print vels(speed,turn)
                if (status == 14):
                    print msg
                status = (status + 1) % 15
            else:
                x = 0
                th = 0
                if (key == '\x03'):
                    break

            twist = Twist()
            twist.linear.x = x*speed; twist.linear.y = 0; twist.linear.z = 0
            twist.angular.x = 0; twist.angular.y = 0; twist.angular.z = th*turn
            pub.publish(twist)

    except:
        print e

    finally:
        twist = Twist()
        twist.linear.x = 0; twist.linear.y = 0; twist.linear.z = 0
        twist.angular.x = 0; twist.angular.y = 0; twist.angular.z = 0
        pub.publish(twist)

    termios.tcsetattr(sys.stdin, termios.TCSADRAIN, settings)

