from pybind11_tests import iostream as m

import sys

from contextlib import contextmanager

try:

    # Python 3

    from io import StringIO

except ImportError:

    # Python 2

    try:

        from cStringIO import StringIO

    except ImportError:

        from StringIO import StringIO

try:

    # Python 3.4

    from contextlib import redirect_stdout

except ImportError:

    @contextmanager

    def redirect_stdout(target):

        original = sys.stdout

        sys.stdout = target

        yield

        sys.stdout = original

try:

    # Python 3.5

    from contextlib import redirect_stderr

except ImportError:

    @contextmanager

    def redirect_stderr(target):

        original = sys.stderr

        sys.stderr = target

        yield

        sys.stderr = original

def test_captured(capsys):

    msg = "I've been redirected to Python, I hope!"

    m.captured_output(msg)

    stdout, stderr = capsys.readouterr()

    assert stdout == msg

    assert stderr == ''

    m.captured_output_default(msg)

    stdout, stderr = capsys.readouterr()

    assert stdout == msg

    assert stderr == ''

    m.captured_err(msg)

    stdout, stderr = capsys.readouterr()

    assert stdout == ''

    assert stderr == msg

def test_captured_large_string(capsys):

    # Make this bigger than the buffer used on the C++ side: 1024 chars

    msg = "I've been redirected to Python, I hope!"

    msg = msg * (1024 // len(msg) + 1)

    m.captured_output_default(msg)

    stdout, stderr = capsys.readouterr()

    assert stdout == msg

    assert stderr == ''

def test_guard_capture(capsys):

    msg = "I've been redirected to Python, I hope!"

    m.guard_output(msg)

    stdout, stderr = capsys.readouterr()

    assert stdout == msg

    assert stderr == ''

def test_series_captured(capture):

    with capture:

        m.captured_output("a")

        m.captured_output("b")

    assert capture == "ab"

def test_flush(capfd):

    msg = "(not flushed)"

    msg2 = "(flushed)"

    with m.ostream_redirect():

        m.noisy_function(msg, flush=False)

        stdout, stderr = capfd.readouterr()

        assert stdout == ''

        m.noisy_function(msg2, flush=True)

        stdout, stderr = capfd.readouterr()

        assert stdout == msg + msg2

        m.noisy_function(msg, flush=False)

    stdout, stderr = capfd.readouterr()

    assert stdout == msg

def test_not_captured(capfd):

    msg = "Something that should not show up in log"

    stream = StringIO()

    with redirect_stdout(stream):

        m.raw_output(msg)

    stdout, stderr = capfd.readouterr()

    assert stdout == msg

    assert stderr == ''

    assert stream.getvalue() == ''

    stream = StringIO()

    with redirect_stdout(stream):

        m.captured_output(msg)

    stdout, stderr = capfd.readouterr()

    assert stdout == ''

    assert stderr == ''

    assert stream.getvalue() == msg

def test_err(capfd):

    msg = "Something that should not show up in log"

    stream = StringIO()

    with redirect_stderr(stream):

        m.raw_err(msg)

    stdout, stderr = capfd.readouterr()

    assert stdout == ''

    assert stderr == msg

    assert stream.getvalue() == ''

    stream = StringIO()

    with redirect_stderr(stream):

        m.captured_err(msg)

    stdout, stderr = capfd.readouterr()

    assert stdout == ''

    assert stderr == ''

    assert stream.getvalue() == msg

def test_multi_captured(capfd):

    stream = StringIO()

    with redirect_stdout(stream):

        m.captured_output("a")

        m.raw_output("b")

        m.captured_output("c")

        m.raw_output("d")

    stdout, stderr = capfd.readouterr()

    assert stdout == 'bd'

    assert stream.getvalue() == 'ac'

def test_dual(capsys):

    m.captured_dual("a", "b")

    stdout, stderr = capsys.readouterr()

    assert stdout == "a"

    assert stderr == "b"

def test_redirect(capfd):

    msg = "Should not be in log!"

    stream = StringIO()

    with redirect_stdout(stream):

        m.raw_output(msg)

    stdout, stderr = capfd.readouterr()

    assert stdout == msg

    assert stream.getvalue() == ''

    stream = StringIO()

    with redirect_stdout(stream):

        with m.ostream_redirect():

            m.raw_output(msg)

    stdout, stderr = capfd.readouterr()

    assert stdout == ''

    assert stream.getvalue() == msg

    stream = StringIO()

    with redirect_stdout(stream):

        m.raw_output(msg)

    stdout, stderr = capfd.readouterr()

    assert stdout == msg

    assert stream.getvalue() == ''

def test_redirect_err(capfd):

    msg = "StdOut"

    msg2 = "StdErr"

    stream = StringIO()

    with redirect_stderr(stream):

        with m.ostream_redirect(stdout=False):

            m.raw_output(msg)

            m.raw_err(msg2)

    stdout, stderr = capfd.readouterr()

    assert stdout == msg

    assert stderr == ''

    assert stream.getvalue() == msg2

def test_redirect_both(capfd):

    msg = "StdOut"

    msg2 = "StdErr"

    stream = StringIO()

    stream2 = StringIO()

    with redirect_stdout(stream):

        with redirect_stderr(stream2):

            with m.ostream_redirect():

                m.raw_output(msg)

                m.raw_err(msg2)

    stdout, stderr = capfd.readouterr()

    assert stdout == ''

    assert stderr == ''

    assert stream.getvalue() == msg

    assert stream2.getvalue() == msg2