#!/usr/bin/env python

#

# Copyright (C) 2016 g10 Code GmbH

# Copyright (C) 2004,2008 Igor Belyi <belyi@users.sourceforge.net>

# Copyright (c) 2008 Bernhard Reiter <bernhard@intevation.de>

#

# 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, see <https://www.gnu.org/licenses/>.

from __future__ import absolute_import, print_function, unicode_literals

import sys

import gpg

del absolute_import, print_function, unicode_literals

def print_engine_infos():

    print("gpgme version:", gpg.core.check_version(None))

    print("engines:")

    for engine in gpg.core.get_engine_info():

        print(engine.file_name, engine.version)

    for proto in [gpg.constants.protocol.OpenPGP, gpg.constants.protocol.CMS]:

        print("Have {}? {}".format(

            gpg.core.get_protocol_name(proto),

            gpg.core.engine_check_version(proto)))

def verifyprintdetails(filename, detached_sig_filename=None):

    """Verify a signature, print a lot of details."""

    with gpg.Context() as c:

        # Verify.

        data, result = c.verify(

            open(filename),

            open(detached_sig_filename) if detached_sig_filename else None)

        # List results for all signatures. Status equal 0 means "Ok".

        for index, sign in enumerate(result.signatures):

            print("signature", index, ":")

            print("  summary:     %#0x" % (sign.summary))

            print("  status:      %#0x" % (sign.status))

            print("  timestamp:  ", sign.timestamp)

            print("  fingerprint:", sign.fpr)

            print("  uid:        ", c.get_key(sign.fpr).uids[0].uid)

    # Print "unsigned" text if inline signature

    if data:

        sys.stdout.buffer.write(data)

def main():

    print_engine_infos()

    print()

    argc = len(sys.argv)

    if argc < 2 or argc > 3:

        sys.exit("Usage: {} <filename>[ <detached_signature_filename>]".format(

            sys.argv[0]))

    if argc == 2:

        print("trying to verify file {}.".format(sys.argv[1]))

        verifyprintdetails(sys.argv[1])

    if argc == 3:

        print("trying to verify signature {1} for file {0}.".format(*sys.argv))

        verifyprintdetails(sys.argv[1], sys.argv[2])

if __name__ == "__main__":

    main()