from __future__ import absolute_import, division, print_function, with_statement

import traceback

from tornado.concurrent import Future
from tornado.httpclient import HTTPError, HTTPRequest
from tornado.log import gen_log
from tornado.testing import AsyncHTTPTestCase, gen_test, bind_unused_port, ExpectLog
from tornado.test.util import unittest, skipOnTravis
from tornado.web import Application, RequestHandler

try:
    import tornado.websocket
    from tornado.util import _websocket_mask_python
except ImportError:
    # The unittest module presents misleading errors on ImportError
    # (it acts as if websocket_test could not be found, hiding the underlying
    # error).  If we get an ImportError here (which could happen due to
    # TORNADO_EXTENSION=1), print some extra information before failing.
    traceback.print_exc()
    raise

from tornado.websocket import WebSocketHandler, websocket_connect, WebSocketError

try:
    from tornado import speedups
except ImportError:
    speedups = None


class TestWebSocketHandler(WebSocketHandler):
    """Base class for testing handlers that exposes the on_close event.

    This allows for deterministic cleanup of the associated socket.
    """
    def initialize(self, close_future):
        self.close_future = close_future

    def on_close(self):
        self.close_future.set_result(None)


class EchoHandler(TestWebSocketHandler):
    def on_message(self, message):
        self.write_message(message, isinstance(message, bytes))


class HeaderHandler(TestWebSocketHandler):
    def open(self):
        self.write_message(self.request.headers.get('X-Test', ''))


class NonWebSocketHandler(RequestHandler):
    def get(self):
        self.write('ok')


class WebSocketTest(AsyncHTTPTestCase):
    def get_app(self):
        self.close_future = Future()
        return Application([
            ('/echo', EchoHandler, dict(close_future=self.close_future)),
            ('/non_ws', NonWebSocketHandler),
            ('/header', HeaderHandler, dict(close_future=self.close_future)),
        ])

    @gen_test
    def test_websocket_gen(self):
        ws = yield websocket_connect(
            'ws://localhost:%d/echo' % self.get_http_port(),
            io_loop=self.io_loop)
        ws.write_message('hello')
        response = yield ws.read_message()
        self.assertEqual(response, 'hello')
        ws.close()
        yield self.close_future

    def test_websocket_callbacks(self):
        websocket_connect(
            'ws://localhost:%d/echo' % self.get_http_port(),
            io_loop=self.io_loop, callback=self.stop)
        ws = self.wait().result()
        ws.write_message('hello')
        ws.read_message(self.stop)
        response = self.wait().result()
        self.assertEqual(response, 'hello')
        ws.close()
        yield self.close_future

    @gen_test
    def test_websocket_http_fail(self):
        with self.assertRaises(HTTPError) as cm:
            yield websocket_connect(
                'ws://localhost:%d/notfound' % self.get_http_port(),
                io_loop=self.io_loop)
        self.assertEqual(cm.exception.code, 404)

    @gen_test
    def test_websocket_http_success(self):
        with self.assertRaises(WebSocketError):
            yield websocket_connect(
                'ws://localhost:%d/non_ws' % self.get_http_port(),
                io_loop=self.io_loop)

    @skipOnTravis
    @gen_test
    def test_websocket_network_timeout(self):
        sock, port = bind_unused_port()
        sock.close()
        with self.assertRaises(HTTPError) as cm:
            with ExpectLog(gen_log, ".*"):
                yield websocket_connect(
                    'ws://localhost:%d/' % port,
                    io_loop=self.io_loop,
                    connect_timeout=0.01)
        self.assertEqual(cm.exception.code, 599)

    @gen_test
    def test_websocket_network_fail(self):
        sock, port = bind_unused_port()
        sock.close()
        with self.assertRaises(HTTPError) as cm:
            with ExpectLog(gen_log, ".*"):
                yield websocket_connect(
                    'ws://localhost:%d/' % port,
                    io_loop=self.io_loop,
                    connect_timeout=3600)
        self.assertEqual(cm.exception.code, 599)

    @gen_test
    def test_websocket_close_buffered_data(self):
        ws = yield websocket_connect(
            'ws://localhost:%d/echo' % self.get_http_port())
        ws.write_message('hello')
        ws.write_message('world')
        ws.stream.close()
        yield self.close_future

    @gen_test
    def test_websocket_headers(self):
        # Ensure that arbitrary headers can be passed through websocket_connect.
        ws = yield websocket_connect(
            HTTPRequest('ws://localhost:%d/header' % self.get_http_port(),
                        headers={'X-Test': 'hello'}))
        response = yield ws.read_message()
        self.assertEqual(response, 'hello')
        ws.close()
        yield self.close_future


class MaskFunctionMixin(object):
    # Subclasses should define self.mask(mask, data)
    def test_mask(self):
        self.assertEqual(self.mask(b'abcd', b''), b'')
        self.assertEqual(self.mask(b'abcd', b'b'), b'\x03')
        self.assertEqual(self.mask(b'abcd', b'54321'), b'TVPVP')
        self.assertEqual(self.mask(b'ZXCV', b'98765432'), b'c`t`olpd')
        # Include test cases with \x00 bytes (to ensure that the C
        # extension isn't depending on null-terminated strings) and
        # bytes with the high bit set (to smoke out signedness issues).
        self.assertEqual(self.mask(b'\x00\x01\x02\x03',
                                   b'\xff\xfb\xfd\xfc\xfe\xfa'),
                         b'\xff\xfa\xff\xff\xfe\xfb')
        self.assertEqual(self.mask(b'\xff\xfb\xfd\xfc',
                                   b'\x00\x01\x02\x03\x04\x05'),
                         b'\xff\xfa\xff\xff\xfb\xfe')


class PythonMaskFunctionTest(MaskFunctionMixin, unittest.TestCase):
    def mask(self, mask, data):
        return _websocket_mask_python(mask, data)


@unittest.skipIf(speedups is None, "tornado.speedups module not present")
class CythonMaskFunctionTest(MaskFunctionMixin, unittest.TestCase):
    def mask(self, mask, data):
        return speedups.websocket_mask(mask, data)