#!/usr/bin/env python3

# asn2deb - quick hack by W. Borgert <debacle@debian.org> to create
# Debian GNU/Linux packages from ASN.1 files for Wireshark.
# Copyright 2004, W. Borgert

# ASN.1 module for Wireshark, use of snacc type table:
# Copyright 2003, Matthijs Melchior <matthijs.melchior@xs4all.nl>
#
# Wireshark - Network traffic analyzer
# By Gerald Combs <gerald@wireshark.com>
# Copyright 1998 Gerald Combs

# SPDX-License-Identifier: GPL-2.0-or-later

import getopt, os, string, sys, time

scriptinfo = """asn2deb version 2004-02-17
Copyright 2004, W. Borgert
Free software, released under the terms of the GPL."""

options = {'asn':      None,
           'dbopts':   "",
           'email':    "invalid@invalid.invalid",
           'help':     0,
           'name':     "No Name",
           'preserve': 0,
           'version':  0}

def create_file(filename, content, mode = None):
    """Create a file with given content."""
    global options
    if options['preserve'] and os.path.isfile(filename):
        return
    f = open(filename, 'w')
    f.write(content)
    f.close()
    if mode:
        os.chmod(filename, mode)

def create_files(version, deb, email, asn, name, iso, rfc):
    """Create all files for the .deb build process."""
    base = asn.lower()[:-5]

    if not os.path.isdir("packaging/debian"):
        os.mkdir("packaging/debian")

    create_file("packaging/debian/rules", """#!/usr/bin/make -f

include /usr/share/cdbs/1/rules/debhelper.mk
include /usr/share/cdbs/1/class/autotools.mk

PREFIX=`pwd`/packaging/debian/wireshark-asn1-%s

binary-post-install/wireshark-asn1-%s::
	rm -f $(PREFIX)/usr/lib/wireshark/plugins/%s/*.a
""" % (base, base, version), 0o755)

    create_file("packaging/debian/control", """Source: wireshark-asn1-%s
Section: net
Priority: optional
Maintainer: %s <%s>
Standards-Version: 3.6.1.0
Build-Depends: snacc, autotools-dev, debhelper, cdbs

Package: wireshark-asn1-%s
Architecture: all
Depends: wireshark (= %s)
Description: ASN.1/BER dissector for %s
 This package provides a type table for decoding BER (Basic Encoding
 Rules) data over TCP or UDP, described by an ASN.1 (Abstract Syntax
 Notation 1) file '%s.asn1'.
""" % (base, name, email, base, deb, base, base))

    create_file("packaging/debian/changelog",
            """wireshark-asn1-%s (0.0.1-1) unstable; urgency=low

  * Automatically created package.

 -- %s <%s>  %s
""" % (base, name, email, rfc + "\n    (" + iso + ")"))

    create_file("packaging/debian/copyright",
            """This package has been created automatically be asn2deb on
%s for Debian GNU/Linux.

Wireshark: https://www.wireshark.com/

Copyright:

GPL, as evidenced by existence of GPL license file \"COPYING\".
(the GNU GPL may be viewed on Debian systems in
/usr/share/common-licenses/GPL)
""" % (iso))

def get_wrs_version():
    """Detect version of wireshark-dev package."""
    deb = os.popen(
        "dpkg-query -W --showformat='${Version}' wireshark-dev").read()
    debv = string.find(deb, "-")
    if debv == -1: debv = len(deb)
    version = deb[string.find(deb, ":")+1:debv]
    return version, deb

def get_time():
    """Detect current time and return ISO and RFC time string."""
    currenttime = time.gmtime()
    return time.strftime("%Y-%m-%d %H:%M:%S +0000", currenttime), \
           time.strftime("%a, %d %b %Y %H:%M:%S +0000", currenttime)

def main():
    global options
    process_opts(sys.argv)
    iso, rfc = get_time()
    version, deb = get_wrs_version()
    create_files(version, deb,
                 options['email'], options['asn'], options['name'],
                 iso, rfc)
    os.system("dpkg-buildpackage " + options['dbopts'])

def process_opts(argv):
    """Process command line options."""
    global options
    try:
        opts, args = getopt.getopt(argv[1:], "a:d:e:hn:pv",
                                   ["asn=",
                                    "dbopts=",
                                    "email=",
                                    "help",
                                    "name=",
                                    "preserve",
                                    "version"])
    except getopt.GetoptError:
        usage(argv[0])
        sys.exit(1)
    for o, a in opts:
        if o in ("-a", "--asn"):
            options['asn'] = a
        if o in ("-d", "--dbopts"):
            options['dbopts'] = a
        if o in ("-e", "--email"):
            options['email'] = a
        if o in ("-h", "--help"):
            options['help'] = 1
        if o in ("-n", "--name"):
            options['name'] = a
        if o in ("-p", "--preserve"):
            options['preserve'] = 1
        if o in ("-v", "--version"):
            options['version'] = 1
    if options['help']:
        usage(argv[0])
        sys.exit(0)
    if options['version']:
        print(scriptinfo)
        sys.exit(0)
    if not options['asn']:
        print("mandatory ASN.1 file parameter missing")
        sys.exit(1)
    if not os.access(options['asn'], os.R_OK):
        print("ASN.1 file not accessible")
        sys.exit(1)

def usage(name):
    """Print usage help."""
    print("Usage: " + name + " <parameters>\n" + \
          "Parameters are\n" + \
          "  --asn      -a asn1file, ASN.1 file to use (mandatory)\n" + \
          "  --dbopts   -d opts,     options for dpkg-buildpackage\n" + \
          "  --email    -e address,  use e-mail address\n" + \
          "  --help     -h,          print help and exit\n" + \
          "  --name     -n name,     use user name\n" + \
          "  --preserve -p,          do not overwrite files\n" + \
          "  --version  -v,          print version and exit\n" + \
          "Example:\n" + \
          name + " -e me@foo.net -a bar.asn1 -n \"My Name\" " + \
          "-d \"-rfakeroot -uc -us\"")
if __name__ == '__main__':
    main()