#!/usr/bin/python2.7

"""image_version <image name>

This tool returns the latest version tag for an image
"""

import re
import sys
import os
import json
import time
import datetime
import tempfile
import subprocess
import shlex
import shutil

def load_versions(filename):
    if not os.path.exists(filename):
        print 'Can\'t find image_versions.json'
        sys.exit(1)
    t = json.loads(file(filename).read())
    versions = {}
    for key in t:
        versions[key.encode('utf-8')] = t[key].encode('utf-8')
    return versions

def main():
    if len(sys.argv) == 1:
        print __doc__
        sys.exit(1)

    image_name = sys.argv[1]
    dir = os.path.dirname(os.path.abspath(sys.argv[0]))
    versions = load_versions(os.path.join(dir, 'image_versions.json'))

    # Does version exist for this image?
    if not versions.has_key(image_name):
        print 'Version not available for %s.' % image_name
        sys.exit(1)

    print versions[image_name]

if __name__ == '__main__':
    main()