#!/usr/bin/env python

# Copyright (C) 2017 g10 Code GmbH
#
# This file is part of GPGME.
#
# GPGME 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.
#
# GPGME 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 Lesser General
# Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this program; if not, see <http://www.gnu.org/licenses/>.

from __future__ import absolute_import, print_function, unicode_literals
del absolute_import, print_function, unicode_literals

import gpg
import itertools
import os
import shutil
import time

import support

alpha = "Alpha <alpha@invalid.example.net>"
bravo = "Bravo <bravo@invalid.example.net>"

def copy_configuration(destination):
    home = os.environ['GNUPGHOME']
    shutil.copy(os.path.join(home, "gpg.conf"), destination)
    shutil.copy(os.path.join(home, "gpg-agent.conf"), destination)

with support.TemporaryDirectory() as tmp:
    copy_configuration(tmp)
    with gpg.Context(home_dir=tmp) as ctx:
        res = ctx.create_key(alpha, certify=True)
        keys = list(ctx.keylist())
        assert len(keys) == 1, "Weird number of keys created"
        key = keys[0]
        assert key.fpr == res.fpr
        assert len(key.subkeys) == 1, "Expected one primary key and no subkeys"

        def get_subkey(fpr):
            k = ctx.get_key(fpr)
            for sk in k.subkeys:
                if sk.fpr == fpr:
                    return sk
            return None

        # Check gpg.constants.create.NOEXPIRE...
        res = ctx.create_subkey(key, expires=False)
        subkey = get_subkey(res.fpr)
        assert subkey.expires == 0, "Expected subkey not to expire"
        assert subkey.can_encrypt, \
            "Default subkey capabilities do not include encryption"

        t = 2 * 24 * 60 * 60
        slack = 5 * 60
        res = ctx.create_subkey(key, expires_in=t)
        subkey = get_subkey(res.fpr)
        assert abs(time.time() + t - subkey.expires) < slack, \
            "subkeys expiration time is off"

        # Check capabilities
        for sign, encrypt, authenticate in itertools.product([False, True],
                                                             [False, True],
                                                             [False, True]):
            # Filter some out
            if not (sign or encrypt or authenticate):
                # This triggers the default capabilities tested before.
                continue

            res = ctx.create_subkey(key, sign=sign, encrypt=encrypt,
                                    authenticate=authenticate)
            subkey = get_subkey(res.fpr)
            assert sign == subkey.can_sign
            assert encrypt == subkey.can_encrypt
            assert authenticate == subkey.can_authenticate

        # Check algorithm
        res = ctx.create_subkey(key, algorithm="rsa")
        subkey = get_subkey(res.fpr)
        assert subkey.pubkey_algo == 1

        # Check algorithm with size
        res = ctx.create_subkey(key, algorithm="rsa1024")
        subkey = get_subkey(res.fpr)
        assert subkey.pubkey_algo == 1
        assert subkey.length == 1024

        # Check algorithm future-default
        ctx.create_subkey(key, algorithm="future-default")

        # Check passphrase protection.  For this we create a new key
        # so that we have a key with just one encryption subkey.
        bravo_res = ctx.create_key(bravo, certify=True)
        bravo_key = ctx.get_key(bravo_res.fpr)
        assert len(bravo_key.subkeys) == 1, "Expected one primary key and no subkeys"

        passphrase = "streng geheim"
        res = ctx.create_subkey(bravo_key, passphrase=passphrase)
        ciphertext, _, _ = ctx.encrypt(b"hello there",
                                       recipients=[ctx.get_key(bravo_res.fpr)])

        cb_called = False
        def cb(*args):
            global cb_called
            cb_called = True
            return passphrase
        ctx.pinentry_mode = gpg.constants.PINENTRY_MODE_LOOPBACK
        ctx.set_passphrase_cb(cb)

        plaintext, _, _ = ctx.decrypt(ciphertext)
        assert plaintext == b"hello there"
        assert cb_called