# vim: ft=python fileencoding=utf-8 sts=4 sw=4 et:

# Copyright 2015-2016 Florian Bruhin (The Compiler) <mail@qutebrowser.org>
#
# This file is part of qutebrowser.
#
# qutebrowser 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 3 of the License, or
# (at your option) any later version.
#
# qutebrowser 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 qutebrowser.  If not, see <http://www.gnu.org/licenses/>.

"""Test testprocess.Process."""

import sys
import time
import contextlib
import datetime

import pytest
from PyQt5.QtCore import QProcess

from end2end.fixtures import testprocess

pytestmark = [pytest.mark.not_frozen]


@contextlib.contextmanager
def stopwatch(min_ms=None, max_ms=None):
    if min_ms is None and max_ms is None:
        raise ValueError("Using stopwatch with both min_ms/max_ms None does "
                         "nothing.")
    start = datetime.datetime.now()
    yield
    stop = datetime.datetime.now()
    delta_ms = (stop - start).total_seconds() * 1000
    if min_ms is not None:
        assert delta_ms >= min_ms
    if max_ms is not None:
        assert delta_ms <= max_ms


class PythonProcess(testprocess.Process):

    """A testprocess which runs the given Python code."""

    def __init__(self):
        super().__init__()
        self.proc.setReadChannel(QProcess.StandardOutput)
        self.code = None

    def _parse_line(self, line):
        print("LINE: {}".format(line))
        if line.strip() == 'ready':
            self.ready.emit()
        return testprocess.Line(line)

    def _executable_args(self):
        code = [
            'import sys, time',
            'print("ready")',
            'sys.stdout.flush()',
            self.code,
            'sys.stdout.flush()',
            'time.sleep(20)',
        ]
        return (sys.executable, ['-c', ';'.join(code)])

    def _default_args(self):
        return []


class QuitPythonProcess(PythonProcess):

    """A testprocess which quits immediately."""

    def _executable_args(self):
        code = [
            'import sys',
            'print("ready")',
            'sys.exit(0)',
        ]
        return (sys.executable, ['-c', ';'.join(code)])


class NoReadyPythonProcess(PythonProcess):

    """A testprocess which never emits 'ready' and quits."""

    def _executable_args(self):
        code = [
            'import sys',
            'sys.exit(0)',
        ]
        return (sys.executable, ['-c', ';'.join(code)])


@pytest.fixture
def pyproc():
    proc = PythonProcess()
    yield proc
    proc.terminate()


@pytest.fixture
def quit_pyproc():
    proc = QuitPythonProcess()
    yield proc
    proc.terminate()


@pytest.fixture
def noready_pyproc():
    proc = NoReadyPythonProcess()
    yield proc
    proc.terminate()


def test_no_ready_python_process(noready_pyproc):
    """When a process quits immediately, waiting for start should interrupt."""
    with pytest.raises(testprocess.ProcessExited):
        with stopwatch(max_ms=5000):
            noready_pyproc.start()


def test_quitting_process(qtbot, quit_pyproc):
    with qtbot.waitSignal(quit_pyproc.proc.finished):
        quit_pyproc.start()
    with pytest.raises(testprocess.ProcessExited):
        quit_pyproc.after_test()


def test_quitting_process_expected(qtbot, quit_pyproc):
    with qtbot.waitSignal(quit_pyproc.proc.finished):
        quit_pyproc.start()
    quit_pyproc.exit_expected = True
    quit_pyproc.after_test()


def test_process_never_started(qtbot, quit_pyproc):
    """Calling after_test without start should not fail."""
    quit_pyproc.after_test()


def test_wait_signal_raising(qtbot):
    """testprocess._wait_signal should raise by default."""
    proc = testprocess.Process()
    with pytest.raises(qtbot.TimeoutError):
        with proc._wait_signal(proc.proc.started, timeout=0):
            pass


def test_custom_environment(pyproc):
    pyproc.code = 'import os; print(os.environ["CUSTOM_ENV"])'
    pyproc.start(env={'CUSTOM_ENV': 'blah'})
    pyproc.wait_for(data='blah')


@pytest.mark.posix
def test_custom_environment_system_env(monkeypatch, pyproc):
    """When env=... is given, the system environment should be present."""
    monkeypatch.setenv('QUTE_TEST_ENV', 'blubb')
    pyproc.code = 'import os; print(os.environ["QUTE_TEST_ENV"])'
    pyproc.start(env={})
    pyproc.wait_for(data='blubb')


class TestWaitFor:

    def test_successful(self, pyproc):
        """Using wait_for with the expected text."""
        pyproc.code = "time.sleep(0.5); print('foobar')"
        with stopwatch(min_ms=500):
            pyproc.start()
            pyproc.wait_for(data="foobar")

    def test_other_text(self, pyproc):
        """Test wait_for when getting some unrelated text."""
        pyproc.code = "time.sleep(0.1); print('blahblah')"
        pyproc.start()
        with pytest.raises(testprocess.WaitForTimeout):
            pyproc.wait_for(data="foobar", timeout=500)

    def test_no_text(self, pyproc):
        """Test wait_for when getting no text at all."""
        pyproc.code = "pass"
        pyproc.start()
        with pytest.raises(testprocess.WaitForTimeout):
            pyproc.wait_for(data="foobar", timeout=100)

    @pytest.mark.parametrize('message', ['foobar', 'literal [x]'])
    def test_existing_message(self, message, pyproc):
        """Test with a message which already passed when waiting."""
        pyproc.code = "print('{}')".format(message)
        pyproc.start()
        time.sleep(0.5)  # to make sure the message is printed
        pyproc.wait_for(data=message)

    def test_existing_message_previous_test(self, pyproc):
        """Make sure the message of a previous test gets ignored."""
        pyproc.code = "print('foobar')"
        pyproc.start()
        line = pyproc.wait_for(data="foobar")
        line.waited_for = False  # so we don't test what the next test does
        pyproc.after_test()
        with pytest.raises(testprocess.WaitForTimeout):
            pyproc.wait_for(data="foobar", timeout=100)

    def test_existing_message_already_waited(self, pyproc):
        """Make sure an existing message doesn't stop waiting twice.

        wait_for checks existing messages (see above), but we don't want it to
        automatically proceed if we already *did* use wait_for on one of the
        existing messages, as that makes it likely it's not what we actually
        want.
        """
        pyproc.code = "time.sleep(0.1); print('foobar')"
        pyproc.start()
        pyproc.wait_for(data="foobar")
        with pytest.raises(testprocess.WaitForTimeout):
            pyproc.wait_for(data="foobar", timeout=100)

    def test_no_kwargs(self, pyproc):
        """Using wait_for without kwargs should raise an exception.

        Otherwise it'd match automatically because of the all(matches).
        """
        with pytest.raises(TypeError):
            pyproc.wait_for()

    def test_do_skip(self, pyproc):
        """Test wait_for when getting no text at all, with do_skip."""
        pyproc.code = "pass"
        pyproc.start()
        with pytest.raises(pytest.skip.Exception):
            pyproc.wait_for(data="foobar", timeout=100, do_skip=True)


class TestEnsureNotLogged:

    @pytest.mark.parametrize('message, pattern', [
        ('blacklisted', 'blacklisted'),
        ('bl[a]cklisted', 'bl[a]cklisted'),
        ('blacklisted', 'black*'),
    ])
    def test_existing_message(self, pyproc, message, pattern):
        pyproc.code = "print('{}')".format(message)
        pyproc.start()
        with stopwatch(max_ms=1000):
            with pytest.raises(testprocess.BlacklistedMessageError):
                pyproc.ensure_not_logged(data=pattern, delay=2000)

    def test_late_message(self, pyproc):
        pyproc.code = "time.sleep(0.5); print('blacklisted')"
        pyproc.start()
        with pytest.raises(testprocess.BlacklistedMessageError):
            pyproc.ensure_not_logged(data='blacklisted', delay=5000)

    def test_no_matching_message(self, pyproc):
        pyproc.code = "print('blacklisted... nope!')"
        pyproc.start()
        pyproc.ensure_not_logged(data='blacklisted', delay=100)

    def test_wait_for_and_blacklist(self, pyproc):
        pyproc.code = "print('blacklisted')"
        pyproc.start()
        pyproc.wait_for(data='blacklisted')
        with pytest.raises(testprocess.BlacklistedMessageError):
            pyproc.ensure_not_logged(data='blacklisted', delay=0)
