# coding=utf8
# mainloop/jm_tests.py -- testcases for JSON-parsing state machine abstraction
#
# Copyright (C) 2015  Codethink Limited
#
# 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; version 2 of the License.
#
# 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.,
# 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA..


import contextlib
import logging
import socket
import unittest

import distbuild


class JsonMachineTests(unittest.TestCase):
    def setUp(self):
        self.loop = distbuild.MainLoop()

    @contextlib.contextmanager
    def listening_json_machine(self, port):
        '''Return a writable socket connected to an example JSON machine.

        This example uses the code path that listens for incoming build jobs
        from remote machines running `morph distbuild`.

        '''
        listener = distbuild.ListenServer(
            'localhost', port, distbuild.InitiatorConnection, [None, None])
        self.loop.add_state_machine(listener)

        listen_socket = socket.socket()
        try:
            listen_socket.connect(('localhost', port))
            self.loop._run_once()
            yield listen_socket
        finally:
            logging.info('Shutting down test connection handler')
            listen_socket.shutdown(socket.SHUT_RDWR)
            listener.close()
            self.loop.run()

    def test_invalid_input(self):
        '''Distbuild processes must be robust against invalid input.

        Anyone can write to the port that listens for connections from the
        `morph distbuild` command. It should not be possible to break the
        distbuild controller by sending it unexpected input.

        '''
        def send_and_process(string):
            sock.sendall(string + '\n')
            self.loop._run_once()

        invalid_inputs = [
            'fooin',
            '{ "foo": "bar" }',
            bytearray([1, 185, 5, 53]),
        ]

        with self.listening_json_machine(7979) as sock:
            for message in invalid_inputs:
                send_and_process(message)