#!/usr/bin/python
# Given as input two live images, print out differences in their RPM content.
#
# Licensed under the new-BSD license (http://www.opensource.org/licenses/bsd-license.php)
# Copyright (C) 2010 Red Hat, Inc.
# Written by Colin Walters <walters@verbum.org>

import os
import sys
import tempfile
import subprocess
import getopt


def usage(ecode):
    print "Usage: %s img1.iso img2.iso" % (sys.argv[0], )
    print "Print differences between two live images"
    sys.exit(ecode)

def main():
    try:
        opts,args = getopt.getopt(sys.argv[1:], 'h', ['help', 'debug'])
    except getopt.GetoptError, e:
        usage(1)
        
    version = None
    debug = False
    for o,a in opts:
        if o in ('-h', '--help'):
            usage(0)
        elif o in ('--debug', ):
            debug = True
        
    if len(args) != 2:
        usage(1)
    original = args[0]
    new = args[1]    

    mount_temp = tempfile.mkdtemp()

    (fd, original_rpmdata) = tempfile.mkstemp()
    subprocess.check_call(['../livecd/tools/liveimage-mount', '--mount-hacks', '--chroot',
                           original, mount_temp, 'rpm', '-qa', '--queryformat="%{NAME} %{SIZE}\n'],
                           stdout=fd, stderr=sys.stderr)
    os.close(fd)
    (fd, new_rpmdata) = tempfile.mkstemp()
    subprocess.check_call(['../livecd/tools/liveimage-mount', '--mount-hacks', '--chroot',
                           new, mount_temp, 'rpm', '-qa', '--queryformat="%{NAME} %{SIZE}\n'],
                           stdout=fd, stderr=sys.stderr)
    os.close(fd)
    
    os.rmdir(mount_temp)
    
    original_rpms = {}
    new_rpms = {}
    
    def read_rpmdata(filename, data):
        f = open(filename)
        for line in f:
            line = line.strip()
            if not line: break
            (rpm, size) = line.split(' ', 1)
            data[rpm] = int(size)
        f.close()
    read_rpmdata(original_rpmdata, original_rpms)
    read_rpmdata(new_rpmdata, new_rpms)

    original_set = set(original_rpms)
    new_set = set(new_rpms)
    intersection = original_set.intersection(new_set)
    intersection_deltas = {}
    for rpm in intersection:
        delta = new_rpms[rpm] - original_rpms[rpm]
        if delta != 0:
            intersection_deltas[rpm] = delta
    
    added_set = new_set - original_set
    removed_set = original_set - new_set
    for rpm in sorted(added_set, lambda a,b: cmp(new_rpms[a], new_rpms[b])):
        print '+ %s %d' % (rpm, new_rpms[rpm])
    for rpm in sorted(removed_set, lambda a,b: cmp(original_rpms[a], original_rpms[b])):
        print '- %s %d' % (rpm, original_rpms[rpm])
        
    for rpm in sorted(intersection_deltas, lambda a,b: cmp(intersection_deltas[a], intersection_deltas[b])):
        print '= %s %d' % (rpm, intersection_deltas[rpm])
 
    sys.exit(0)

if __name__ == '__main__':
    main()