"""Test CLI utilities"""
# Copyright © 2020  Brett Smith
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program 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 Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <https://www.gnu.org/licenses/>.

import argparse
import errno
import io
import inspect
import logging
import os
import re
import traceback

import pytest

from conservancy_beancount import cliutil

class AlwaysEqual:
    def __eq__(self, other):
        return True


class MockTraceback:
    def __init__(self, stack=None, index=0):
        if stack is None:
            stack = inspect.stack(context=False)
        self._stack = stack
        self._index = index
        frame_record = self._stack[self._index]
        self.tb_frame = frame_record.frame
        self.tb_lineno = frame_record.lineno

    @property
    def tb_next(self):
        try:
            return type(self)(self._stack, self._index + 1)
        except IndexError:
            return None


@pytest.fixture(scope='module')
def argparser():
    parser = argparse.ArgumentParser(prog='test_cliutil')
    cliutil.add_loglevel_argument(parser)
    cliutil.add_version_argument(parser)
    return parser

@pytest.mark.parametrize('errnum', [
    errno.EACCES,
    errno.EPERM,
    errno.ENOENT,
])
def test_excepthook_oserror(errnum, caplog):
    error = OSError(errnum, os.strerror(errnum), 'TestFilename')
    with pytest.raises(SystemExit) as exc_check:
        cliutil.ExceptHook()(type(error), error, None)
    assert exc_check.value.args[0] == 4
    assert caplog.records
    for log in caplog.records:
        assert log.levelname == 'CRITICAL'
        assert log.message == f"I/O error: {error.filename}: {error.strerror}"

@pytest.mark.parametrize('exc_type', [
    AttributeError,
    RuntimeError,
    ValueError,
])
def test_excepthook_bug(exc_type, caplog):
    error = exc_type("test message")
    with pytest.raises(SystemExit) as exc_check:
        cliutil.ExceptHook()(exc_type, error, None)
    assert exc_check.value.args[0] == 3
    assert caplog.records
    for log in caplog.records:
        assert log.levelname == 'CRITICAL'
        assert log.message == f"internal {exc_type.__name__}: {error.args[0]}"

def test_excepthook_traceback(caplog):
    error = KeyError('test')
    args = (type(error), error, MockTraceback())
    caplog.set_level(logging.DEBUG)
    with pytest.raises(SystemExit) as exc_check:
        cliutil.ExceptHook()(*args)
    assert caplog.records
    assert caplog.records[-1].message == ''.join(traceback.format_exception(*args))

@pytest.mark.parametrize('prog_name,expected', [
    ('', False),
    (AlwaysEqual(), True),
])
def test_is_main_script(prog_name, expected):
    assert cliutil.is_main_script(prog_name) == expected

@pytest.mark.parametrize('arg,expected', [
    ('debug', logging.DEBUG),
    ('info', logging.INFO),
    ('warning', logging.WARNING),
    ('warn', logging.WARNING),
    ('error', logging.ERROR),
    ('err', logging.ERROR),
    ('critical', logging.CRITICAL),
    ('crit', logging.CRITICAL),
])
def test_loglevel_argument(argparser, arg, expected):
    for method in ['lower', 'title', 'upper']:
        args = argparser.parse_args(['--loglevel', getattr(arg, method)()])
        assert args.loglevel is expected

def test_setup_logger():
    stream = io.StringIO()
    logger = cliutil.setup_logger(
        'test_cliutil', logging.INFO, stream, '%(name)s %(levelname)s: %(message)s',
    )
    logger.debug("test debug")
    logger.info("test info")
    assert stream.getvalue() == "test_cliutil INFO: test info\n"

@pytest.mark.parametrize('arg', [
    '--license',
    '--version',
    '--copyright',
])
def test_version_argument(argparser, capsys, arg):
    with pytest.raises(SystemExit) as exc_check:
        args = argparser.parse_args(['--version'])
    assert exc_check.value.args[0] == 0
    stdout, _ = capsys.readouterr()
    lines = iter(stdout.splitlines())
    assert re.match(r'^test_cliutil version \d+\.\d+\.\d+', next(lines, "<EOF>"))