#!/usr/bin/env python

# Copyright (c) 2008, 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
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.

USAGE = "Usage: rosversion <stack> or rosversion -d"

import os
import sys
import rospkg
import traceback

# for < fuerte, retrieve from roscore file
def get_distro_name_from_roscore():
    rospack = rospkg.RosPack()
    # there's some chance that the location of this file changes in the future
    try:
        roslaunch_dir = rospack.get_path('roslaunch')
        roscore_file = os.path.join(roslaunch_dir, 'roscore.xml')
        if not os.path.exists(roscore_file):
            return None
    except:
        return None
    
    distro_name = None

    import xml.dom.minidom
    try:
        dom = xml.dom.minidom.parse(roscore_file)
        tags = dom.getElementsByTagName("param")
        for t in tags:
            if t.hasAttribute('name') and t.getAttribute('name') == 'rosdistro':
                return t.getAttribute('value')
    except:
        traceback.print_exc()
    
if len(sys.argv) == 2:
    stack_name = sys.argv[1]

    if stack_name == '-d' or stack_name == '--distro':
        if 'ROS_DISTRO' in os.environ:
            distro_name = os.environ['ROS_DISTRO']
        else:
            distro_name = get_distro_name_from_roscore()
        if not distro_name:
            sys.stdout.write('<unknown>')
        else:
            sys.stdout.write(distro_name)
        sys.exit(0)
    
    rosstack = rospkg.RosStack()
    try:
        version = rosstack.get_stack_version(stack_name)
    except rospkg.ResourceNotFound as e:
        sys.stderr.write("Cannot locate [%s]"%(stack_name))
        sys.exit(1)

    if version is None:
        sys.stdout.write('<unversioned>')
    else:
        sys.stdout.write(version)
else:
    sys.stderr.write(USAGE+'\n')
    sys.exit(os.EX_USAGE)
