# -*- coding: utf-8 -*-
"Core blessed Terminal() tests."

# std
import collections
import warnings
import platform
import locale
import time
import math
import sys
import imp
import os
import io

# local
from .accessories import (
    as_subprocess,
    TestTerminal,
    unicode_cap,
    all_terms
)

# 3rd party
import mock
import pytest
import six


def test_export_only_Terminal():
    "Ensure only Terminal instance is exported for import * statements."
    import blessed
    assert blessed.__all__ == ('Terminal',)


def test_null_location(all_terms):
    "Make sure ``location()`` with no args just does position restoration."
    @as_subprocess
    def child(kind):
        t = TestTerminal(stream=six.StringIO(), force_styling=True)
        with t.location():
            pass
        expected_output = u''.join(
            (unicode_cap('sc'), unicode_cap('rc')))
        assert (t.stream.getvalue() == expected_output)

    child(all_terms)


def test_flipped_location_move(all_terms):
    "``location()`` and ``move()`` receive counter-example arguments."
    @as_subprocess
    def child(kind):
        buf = six.StringIO()
        t = TestTerminal(stream=buf, force_styling=True)
        y, x = 10, 20
        with t.location(y, x):
            xy_val = t.move(x, y)
            yx_val = buf.getvalue()[len(t.sc):]
            assert xy_val == yx_val

    child(all_terms)


def test_yield_keypad():
    "Ensure ``keypad()`` writes keyboard_xmit and keyboard_local."
    @as_subprocess
    def child(kind):
        # given,
        t = TestTerminal(stream=six.StringIO(), force_styling=True)
        expected_output = u''.join((t.smkx, t.rmkx))

        # exercise,
        with t.keypad():
            pass

        # verify.
        assert (t.stream.getvalue() == expected_output)

    child(kind='xterm')


def test_null_fileno():
    "Make sure ``Terminal`` works when ``fileno`` is ``None``."
    @as_subprocess
    def child():
        # This simulates piping output to another program.
        out = six.StringIO()
        out.fileno = None
        t = TestTerminal(stream=out)
        assert (t.save == u'')

    child()


def test_number_of_colors_without_tty():
    "``number_of_colors`` should return 0 when there's no tty."
    @as_subprocess
    def child_256_nostyle():
        t = TestTerminal(stream=six.StringIO())
        assert (t.number_of_colors == 0)

    @as_subprocess
    def child_256_forcestyle():
        t = TestTerminal(stream=six.StringIO(), force_styling=True)
        assert (t.number_of_colors == 256)

    @as_subprocess
    def child_8_forcestyle():
        kind = 'ansi'
        if platform.system().lower() == 'freebsd':
            # 'ansi' on freebsd returns 0 colors, we use the 'cons25' driver,
            # compatible with its kernel tty.c
            kind = 'cons25'
        t = TestTerminal(kind=kind, stream=six.StringIO(),
                         force_styling=True)
        assert (t.number_of_colors == 8)

    @as_subprocess
    def child_0_forcestyle():
        t = TestTerminal(kind='vt220', stream=six.StringIO(),
                         force_styling=True)
        assert (t.number_of_colors == 0)

    child_0_forcestyle()
    child_8_forcestyle()
    child_256_forcestyle()
    child_256_nostyle()


def test_number_of_colors_with_tty():
    "test ``number_of_colors`` 0, 8, and 256."
    @as_subprocess
    def child_256():
        t = TestTerminal()
        assert (t.number_of_colors == 256)

    @as_subprocess
    def child_8():
        kind = 'ansi'
        if platform.system().lower() == 'freebsd':
            # 'ansi' on freebsd returns 0 colors, we use the 'cons25' driver,
            # compatible with its kernel tty.c
            kind = 'cons25'
        t = TestTerminal(kind=kind)
        assert (t.number_of_colors == 8)

    @as_subprocess
    def child_0():
        t = TestTerminal(kind='vt220')
        assert (t.number_of_colors == 0)

    child_0()
    child_8()
    child_256()


def test_init_descriptor_always_initted(all_terms):
    "Test height and width with non-tty Terminals."
    @as_subprocess
    def child(kind):
        t = TestTerminal(kind=kind, stream=six.StringIO())
        assert t._init_descriptor == sys.__stdout__.fileno()
        assert (isinstance(t.height, int))
        assert (isinstance(t.width, int))
        assert t.height == t._height_and_width()[0]
        assert t.width == t._height_and_width()[1]

    child(all_terms)


def test_force_styling_none(all_terms):
    "If ``force_styling=None`` is used, don't ever do styling."
    @as_subprocess
    def child(kind):
        t = TestTerminal(kind=kind, force_styling=None)
        assert (t.save == '')
        assert (t.color(9) == '')
        assert (t.bold('oi') == 'oi')

    child(all_terms)


def test_setupterm_singleton_issue33():
    "A warning is emitted if a new terminal ``kind`` is used per process."
    @as_subprocess
    def child():
        warnings.filterwarnings("error", category=UserWarning)

        # instantiate first terminal, of type xterm-256color
        term = TestTerminal(force_styling=True)

        try:
            # a second instantiation raises UserWarning
            term = TestTerminal(kind="vt220", force_styling=True)
        except UserWarning:
            err = sys.exc_info()[1]
            assert (err.args[0].startswith(
                    'A terminal of kind "vt220" has been requested')
                    ), err.args[0]
            assert ('a terminal of kind "xterm-256color" will '
                    'continue to be returned' in err.args[0]), err.args[0]
        else:
            # unless term is not a tty and setupterm() is not called
            assert not term.is_a_tty or False, 'Should have thrown exception'
        warnings.resetwarnings()

    child()


def test_setupterm_invalid_issue39():
    "A warning is emitted if TERM is invalid."
    # https://bugzilla.mozilla.org/show_bug.cgi?id=878089
    #
    # if TERM is unset, defaults to 'unknown', which should
    # fail to lookup and emit a warning on *some* systems.
    # freebsd actually has a termcap entry for 'unknown'
    @as_subprocess
    def child():
        warnings.filterwarnings("error", category=UserWarning)

        try:
            term = TestTerminal(kind='unknown', force_styling=True)
        except UserWarning:
            err = sys.exc_info()[1]
            assert err.args[0] == (
                "Failed to setupterm(kind='unknown'): "
                "setupterm: could not find terminal")
        else:
            if platform.system().lower() != 'freebsd':
                assert not term.is_a_tty and not term.does_styling, (
                    'Should have thrown exception')
        warnings.resetwarnings()

    child()


def test_setupterm_invalid_has_no_styling():
    "An unknown TERM type does not perform styling."
    # https://bugzilla.mozilla.org/show_bug.cgi?id=878089

    # if TERM is unset, defaults to 'unknown', which should
    # fail to lookup and emit a warning, only.
    @as_subprocess
    def child():
        warnings.filterwarnings("ignore", category=UserWarning)

        term = TestTerminal(kind='xxXunknownXxx', force_styling=True)
        assert term.kind is None
        assert not term.does_styling
        assert term.number_of_colors == 0
        warnings.resetwarnings()

    child()


def test_missing_ordereddict_uses_module(monkeypatch):
    "ordereddict module is imported when without collections.OrderedDict."
    import blessed.keyboard

    if hasattr(collections, 'OrderedDict'):
        monkeypatch.delattr('collections.OrderedDict')

    try:
        imp.reload(blessed.keyboard)
    except ImportError as err:
        assert err.args[0] in ("No module named ordereddict",  # py2
                               "No module named 'ordereddict'")  # py3
        sys.modules['ordereddict'] = mock.Mock()
        sys.modules['ordereddict'].OrderedDict = -1
        imp.reload(blessed.keyboard)
        assert blessed.keyboard.OrderedDict == -1
        del sys.modules['ordereddict']
        monkeypatch.undo()
        imp.reload(blessed.keyboard)
    else:
        assert platform.python_version_tuple() < ('2', '7')  # reached by py2.6


def test_python3_2_raises_exception(monkeypatch):
    "Test python version 3.0 through 3.2 raises an exception."
    import blessed

    monkeypatch.setattr('platform.python_version_tuple',
                        lambda: ('3', '2', '2'))

    try:
        imp.reload(blessed)
    except ImportError as err:
        assert err.args[0] == (
            'Blessed needs Python 3.2.3 or greater for Python 3 '
            'support due to http://bugs.python.org/issue10570.')
        monkeypatch.undo()
        imp.reload(blessed)
    else:
        assert False, 'Exception should have been raised'


def test_without_dunder():
    "Ensure dunder does not remain in module (py2x InterruptedError test."
    import blessed.terminal
    assert '_' not in dir(blessed.terminal)


def test_IOUnsupportedOperation():
    "Ensure stream that throws IOUnsupportedOperation results in non-tty."
    @as_subprocess
    def child():
        import blessed.terminal

        def side_effect():
            raise io.UnsupportedOperation

        mock_stream = mock.Mock()
        mock_stream.fileno = side_effect

        term = TestTerminal(stream=mock_stream)
        assert term.stream == mock_stream
        assert not term.does_styling
        assert not term.is_a_tty
        assert term.number_of_colors == 0

    child()


def test_winsize_IOError_returns_environ():
    """When _winsize raises IOError, defaults from os.environ given."""
    @as_subprocess
    def child():
        def side_effect(fd):
            raise IOError

        term = TestTerminal()
        term._winsize = side_effect
        os.environ['COLUMNS'] = '1984'
        os.environ['LINES'] = '1888'
        assert term._height_and_width() == (1888, 1984, None, None)

    child()


def test_yield_fullscreen(all_terms):
    "Ensure ``fullscreen()`` writes enter_fullscreen and exit_fullscreen."
    @as_subprocess
    def child(kind):
        t = TestTerminal(stream=six.StringIO(), force_styling=True)
        t.enter_fullscreen = u'BEGIN'
        t.exit_fullscreen = u'END'
        with t.fullscreen():
            pass
        expected_output = u''.join((t.enter_fullscreen, t.exit_fullscreen))
        assert (t.stream.getvalue() == expected_output)

    child(all_terms)


def test_yield_hidden_cursor(all_terms):
    "Ensure ``hidden_cursor()`` writes hide_cursor and normal_cursor."
    @as_subprocess
    def child(kind):
        t = TestTerminal(stream=six.StringIO(), force_styling=True)
        t.hide_cursor = u'BEGIN'
        t.normal_cursor = u'END'
        with t.hidden_cursor():
            pass
        expected_output = u''.join((t.hide_cursor, t.normal_cursor))
        assert (t.stream.getvalue() == expected_output)

    child(all_terms)


def test_no_preferredencoding_fallback_ascii():
    "Ensure empty preferredencoding value defaults to ascii."
    @as_subprocess
    def child():
        with mock.patch('locale.getpreferredencoding') as get_enc:
            get_enc.return_value = u''
            t = TestTerminal()
            assert t._encoding == 'ascii'

    child()


def test_unknown_preferredencoding_warned_and_fallback_ascii():
    """Ensure a locale without a codec emits a warning."""
    @as_subprocess
    def child():
        with mock.patch('locale.getpreferredencoding') as get_enc:
            with warnings.catch_warnings(record=True) as warned:
                get_enc.return_value = '---unknown--encoding---'
                t = TestTerminal()
                assert t._encoding == 'ascii'
                assert len(warned) == 1
                assert issubclass(warned[-1].category, UserWarning)
                assert "fallback to ASCII" in str(warned[-1].message)

    child()


def test_win32_missing_tty_modules(monkeypatch):
    "Ensure dummy exception is used when io is without UnsupportedOperation."
    @as_subprocess
    def child():
        OLD_STYLE = False
        try:
            original_import = getattr(__builtins__, '__import__')
            OLD_STYLE = True
        except AttributeError:
            original_import = __builtins__['__import__']

        tty_modules = ('termios', 'fcntl', 'tty')

        def __import__(name, *args, **kwargs):
            if name in tty_modules:
                raise ImportError
            return original_import(name, *args, **kwargs)

        for module in tty_modules:
            sys.modules.pop(module, None)

        warnings.filterwarnings("error", category=UserWarning)
        try:
            if OLD_STYLE:
                __builtins__.__import__ = __import__
            else:
                __builtins__['__import__'] = __import__
            try:
                import blessed.terminal
                imp.reload(blessed.terminal)
            except UserWarning:
                err = sys.exc_info()[1]
                assert err.args[0] == blessed.terminal._MSG_NOSUPPORT

            warnings.filterwarnings("ignore", category=UserWarning)
            import blessed.terminal
            imp.reload(blessed.terminal)
            assert not blessed.terminal.HAS_TTY
            term = blessed.terminal.Terminal('ansi')
            # https://en.wikipedia.org/wiki/VGA-compatible_text_mode
            # see section '#PC_common_text_modes'
            assert term.height == 25
            assert term.width == 80

        finally:
            if OLD_STYLE:
                setattr(__builtins__, '__import__', original_import)
            else:
                __builtins__['__import__'] = original_import
            warnings.resetwarnings()
            import blessed.terminal
            imp.reload(blessed.terminal)

    child()


def test_time_left():
    """test '_time_left' routine returns correct positive delta difference."""
    from blessed.keyboard import _time_left

    # given stime =~ "10 seconds ago"
    stime = (time.time() - 10)

    # timeleft(now, 15s) = 5s remaining
    timeout = 15
    result = _time_left(stime=stime, timeout=timeout)

    # we expect roughly 4.999s remain
    assert math.ceil(result) == 5.0


def test_time_left_infinite_None():
    """keyboard '_time_left' routine returns None when given None."""
    from blessed.keyboard import _time_left
    assert _time_left(stime=time.time(), timeout=None) is None


def test_termcap_repr():
    "Ensure ``hidden_cursor()`` writes hide_cursor and normal_cursor."

    given_ttype='vt220'
    given_capname = 'cursor_up'
    expected = [r"<Termcap cursor_up:'\x1b\\[A'>",
                r"<Termcap cursor_up:'\\\x1b\\[A'>",
                r"<Termcap cursor_up:u'\\\x1b\\[A'>"]

    @as_subprocess
    def child():
        import blessed
        term = blessed.Terminal(given_ttype)
        given = repr(term.caps[given_capname])
        assert given in expected

    child()
