#!/usr/bin/python
#    
##
# Copyright (C) 2003 by Duke University
# Written by Seth Vidal <skvidal at phy.duke.edu>
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
# 02111-1307, USA.
#

import rpm
import sys
import os



def usage():
    print "Usage: \n\trpmpkgvercmp pkg1 pkg2\n"
    sys.exit(1)
    
    
def returnHdr(ts, package):
    """hand back the rpm header or raise an Error if the pkg is fubar"""
    try:
        fdno = os.open(package, os.O_RDONLY)
    except OSError, e:
        print "Error opening file: %s" % package
        sys.exit(1)
    ts.setVSFlags(~(rpm.RPMVSF_NOMD5|rpm.RPMVSF_NEEDPAYLOAD))
    try:
        hdr = ts.hdrFromFdno(fdno)
    except rpm.error, e:
        print "Error opening package: %s" % package
        sys.exit(1)
    if type(hdr) != rpm.hdr:
        print "Error opening package: %s" % package
        sys.exit(1)
    ts.setVSFlags(0)
    os.close(fdno)
    return hdr

def main(args):
    if len(args) != 2:
        usage()
        
    ts = rpm.TransactionSet()
    pkg1 = args[0]
    pkg2 = args[1]
    hdr1 = returnHdr(ts, pkg1)
    hdr2 = returnHdr(ts, pkg2)
    
    rc = rpm.versionCompare(hdr1, hdr2)

    if rc == 0:
        print "%s and %s have the same rpm epoch-version-release" % (pkg1, pkg2)
        sys.exit(200)
    elif rc < 0:
        print "%s is newer than %s" % (pkg2, pkg1)
        sys.exit(100)
    elif rc > 0:
        print "%s is newer than %s" % (pkg1, pkg2)
        sys.exit(300)

        
    
if __name__ == "__main__":
    main(sys.argv[1:])