"""Configure test fixtures"""

# std imports
import os
import platform
import subprocess

# 3rd party
import pytest

IS_WINDOWS = platform.system() == 'Windows'

all_terms_params = 'xterm screen ansi vt220 rxvt cons25 linux'.split()
many_lines_params = [40, 80]
# we must test a '1' column for conditional in _handle_long_word
many_columns_params = [1, 10]


def envvar_enabled(envvar):
    """
    Return True if environment variable is set and enabled

    unset values, 'no', 0, and 'false' and treated as False regardless of case
    All other values are considered True
    """

    value = os.environ.get(envvar, False)

    if value is False:
        return value

    if value.lower() in {'no', 'false'}:
        return False

    try:
        return bool(int(value))
    except ValueError:
        return True


TEST_FULL = envvar_enabled('TEST_FULL')
TEST_KEYBOARD = envvar_enabled('TEST_KEYBOARD')
TEST_QUICK = envvar_enabled('TEST_QUICK')
TEST_RAW = envvar_enabled('TEST_RAW')


if TEST_FULL:
    try:
        all_terms_params = [
            # use all values of the first column of data in output of 'toe -a'
            _term.split(None, 1)[0] for _term in
            subprocess.Popen(('toe', '-a'),  # pylint: disable=consider-using-with
                             stdout=subprocess.PIPE,
                             close_fds=True)
            .communicate()[0].splitlines()]
    except OSError:
        pass
elif IS_WINDOWS:
    all_terms_params = ['vtwin10', ]
elif TEST_QUICK:
    all_terms_params = 'xterm screen ansi linux'.split()


if TEST_QUICK:
    many_lines_params = [80, ]
    many_columns_params = [25, ]


@pytest.fixture(autouse=True)
def detect_curses_contamination(request):
    """
    Detect when Terminal() is instantiated in parent pytest process.

    The curses module can only call setupterm() once per process. If a test
    instantiates Terminal() in the parent pytest process (instead of within
    @as_subprocess), it contaminates all subsequent tests that try to use
    a different terminal kind.

    This fixture runs automatically for all tests and fails any test that
    initializes curses in the parent process.
    """
    if IS_WINDOWS:
        # Windows doesn't have the curses singleton limitation
        yield
        return

    # Import here to avoid issues if module not yet imported
    import blessed.terminal  # pylint: disable=import-outside-toplevel

    # Record the state before the test
    before = blessed.terminal._CUR_TERM

    # Run the test
    yield

    # Check if curses was initialized during the test
    after = blessed.terminal._CUR_TERM

    if before is None and after is not None:
        # Curses was initialized during this test in the parent process
        test_name = request.node.nodeid
        pytest.fail(
            f"\n{'=' * 70}\n"
            f"CURSES CONTAMINATION DETECTED in parent pytest process!\n"
            f"Test: {test_name}\n"
            f"Terminal kind initialized: {after}\n"
            f"\n"
            f"This test instantiated Terminal() or TestTerminal() in the parent\n"
            f"pytest process instead of within @as_subprocess. This causes curses\n"
            f"to be initialized with a specific terminal kind, which cannot be\n"
            f"changed for the remainder of the test session, breaking later tests!\n"
            f"\n"
            f"FIX: Ensure Terminal() instantiation is within @as_subprocess:\n"
            f"  @as_subprocess\n"
            f"  def child():\n"
            f"      term = TestTerminal(...)\n"
            f"      ...\n"
            f"      assert ..\n"
            f"  child()\n"
            f"{'=' * 70}\n"
        )


@pytest.fixture(params=all_terms_params)
def all_terms(request):
    """Common kind values for all kinds of terminals."""
    return request.param


@pytest.fixture(params=many_lines_params)
def many_lines(request):
    """Various number of lines for screen height."""
    return request.param


@pytest.fixture(params=many_columns_params)
def many_columns(request):
    """Various number of columns for screen width."""
    return request.param