# -*- encoding: utf-8 -*-
from argparse import ArgumentError
try:
    from StringIO import StringIO
except ImportError:
    from io import StringIO

import mock

from cliff.app import App
from cliff.command import Command
from cliff.commandmanager import CommandManager
from cliff.tests import utils
from cliff.utils import damerau_levenshtein, COST


def make_app(**kwargs):
    cmd_mgr = CommandManager('cliff.tests')

    # Register a command that succeeds
    command = mock.MagicMock(spec=Command)
    command_inst = mock.MagicMock(spec=Command)
    command_inst.run.return_value = 0
    command.return_value = command_inst
    cmd_mgr.add_command('mock', command)

    # Register a command that fails
    err_command = mock.Mock(name='err_command', spec=Command)
    err_command_inst = mock.Mock(spec=Command)
    err_command_inst.run = mock.Mock(
        side_effect=RuntimeError('test exception')
    )
    err_command.return_value = err_command_inst
    cmd_mgr.add_command('error', err_command)

    app = App('testing interactive mode',
              '1',
              cmd_mgr,
              stderr=mock.Mock(),  # suppress warning messages
              **kwargs
              )
    return app, command


def test_no_args_triggers_interactive_mode():
    app, command = make_app()
    app.interact = mock.MagicMock(name='inspect')
    app.run([])
    app.interact.assert_called_once_with()


def test_interactive_mode_cmdloop():
    app, command = make_app()
    app.interactive_app_factory = mock.MagicMock(
        name='interactive_app_factory'
    )
    assert app.interpreter is None
    app.run([])
    assert app.interpreter is not None
    app.interactive_app_factory.return_value.cmdloop.assert_called_once_with()


def test_initialize_app():
    app, command = make_app()
    app.initialize_app = mock.MagicMock(name='initialize_app')
    app.run(['mock'])
    app.initialize_app.assert_called_once_with(['mock'])


def test_prepare_to_run_command():
    app, command = make_app()
    app.prepare_to_run_command = mock.MagicMock(name='prepare_to_run_command')
    app.run(['mock'])
    app.prepare_to_run_command.assert_called_once_with(command())


def test_clean_up_success():
    app, command = make_app()
    app.clean_up = mock.MagicMock(name='clean_up')
    app.run(['mock'])
    app.clean_up.assert_called_once_with(command.return_value, 0, None)


def test_clean_up_error():
    app, command = make_app()

    app.clean_up = mock.MagicMock(name='clean_up')
    app.run(['error'])

    app.clean_up.assert_called_once_with(mock.ANY, mock.ANY, mock.ANY)
    call_args = app.clean_up.call_args_list[0]
    assert call_args == mock.call(mock.ANY, 1, mock.ANY)
    args, kwargs = call_args
    assert isinstance(args[2], RuntimeError)
    assert args[2].args == ('test exception',)


def test_clean_up_error_debug():
    app, command = make_app()

    app.clean_up = mock.MagicMock(name='clean_up')
    try:
        app.run(['--debug', 'error'])
    except RuntimeError as err:
        assert app.clean_up.call_args_list[0][0][2] is err
    else:
        assert False, 'Should have had an exception'

    assert app.clean_up.called
    call_args = app.clean_up.call_args_list[0]
    assert call_args == mock.call(mock.ANY, 1, mock.ANY)
    args, kwargs = call_args
    assert isinstance(args[2], RuntimeError)
    assert args[2].args == ('test exception',)


def test_error_handling_clean_up_raises_exception():
    app, command = make_app()

    app.clean_up = mock.MagicMock(
        name='clean_up',
        side_effect=RuntimeError('within clean_up'),
    )
    app.run(['error'])

    assert app.clean_up.called
    call_args = app.clean_up.call_args_list[0]
    assert call_args == mock.call(mock.ANY, 1, mock.ANY)
    args, kwargs = call_args
    assert isinstance(args[2], RuntimeError)
    assert args[2].args == ('test exception',)


def test_error_handling_clean_up_raises_exception_debug():
    app, command = make_app()

    app.clean_up = mock.MagicMock(
        name='clean_up',
        side_effect=RuntimeError('within clean_up'),
    )
    try:
        app.run(['--debug', 'error'])
    except RuntimeError as err:
        if not hasattr(err, '__context__'):
            # The exception passed to clean_up is not the exception
            # caused *by* clean_up.  This test is only valid in python
            # 2 because under v3 the original exception is re-raised
            # with the new one as a __context__ attribute.
            assert app.clean_up.call_args_list[0][0][2] is not err
    else:
        assert False, 'Should have had an exception'

    assert app.clean_up.called
    call_args = app.clean_up.call_args_list[0]
    assert call_args == mock.call(mock.ANY, 1, mock.ANY)
    args, kwargs = call_args
    assert isinstance(args[2], RuntimeError)
    assert args[2].args == ('test exception',)


def test_normal_clean_up_raises_exception():
    app, command = make_app()

    app.clean_up = mock.MagicMock(
        name='clean_up',
        side_effect=RuntimeError('within clean_up'),
    )
    app.run(['mock'])

    assert app.clean_up.called
    call_args = app.clean_up.call_args_list[0]
    assert call_args == mock.call(mock.ANY, 0, None)


def test_normal_clean_up_raises_exception_debug():
    app, command = make_app()

    app.clean_up = mock.MagicMock(
        name='clean_up',
        side_effect=RuntimeError('within clean_up'),
    )
    app.run(['--debug', 'mock'])

    assert app.clean_up.called
    call_args = app.clean_up.call_args_list[0]
    assert call_args == mock.call(mock.ANY, 0, None)


def test_build_option_parser_conflicting_option_should_throw():
    class MyApp(App):
        def __init__(self):
            super(MyApp, self).__init__(
                description='testing',
                version='0.1',
                command_manager=CommandManager('tests'),
            )

        def build_option_parser(self, description, version):
            parser = super(MyApp, self).build_option_parser(description,
                                                            version)
            parser.add_argument(
                '-h', '--help',
                default=self,  # tricky
                help="Show help message and exit.",
            )

    # TODO: tests should really use unittest2.
    try:
        MyApp()
    except ArgumentError:
        pass
    else:
        raise Exception('Exception was not thrown')


def test_option_parser_conflicting_option_custom_arguments_should_not_throw():
    class MyApp(App):
        def __init__(self):
            super(MyApp, self).__init__(
                description='testing',
                version='0.1',
                command_manager=CommandManager('tests'),
            )

        def build_option_parser(self, description, version):
            argparse_kwargs = {'conflict_handler': 'resolve'}
            parser = super(MyApp, self).build_option_parser(
                description,
                version,
                argparse_kwargs=argparse_kwargs)
            parser.add_argument(
                '-h', '--help',
                default=self,  # tricky
                help="Show help message and exit.",
            )

    MyApp()


def test_option_parser_abbrev_issue():
    class MyCommand(Command):
        def get_parser(self, prog_name):
            parser = super(MyCommand, self).get_parser(prog_name)
            parser.add_argument("--end")
            return parser

        def take_action(self, parsed_args):
            assert(parsed_args.end == '123')

    class MyCommandManager(CommandManager):
        def load_commands(self, namespace):
            self.add_command("mycommand", MyCommand)

    class MyApp(App):
        def __init__(self):
            super(MyApp, self).__init__(
                description='testing',
                version='0.1',
                command_manager=MyCommandManager(None),
            )

        def build_option_parser(self, description, version):
            parser = super(MyApp, self).build_option_parser(
                description,
                version,
                argparse_kwargs={'allow_abbrev': False})
            parser.add_argument('--endpoint')
            return parser

    app = MyApp()
    # NOTE(jd) --debug is necessary so assert in take_action() raises correctly
    # here
    app.run(['--debug', 'mycommand', '--end', '123'])


def _test_help(deferred_help):
    app, _ = make_app(deferred_help=deferred_help)
    with mock.patch.object(app, 'initialize_app') as init:
        with mock.patch('cliff.help.HelpAction.__call__',
                        side_effect=SystemExit(0)) as helper:
            try:
                app.run(['--help'])
            except SystemExit:
                pass
            else:
                raise Exception('Exception was not thrown')
            assert helper.called
        assert init.called == deferred_help


def test_help():
    _test_help(False)


def test_deferred_help():
    _test_help(True)


def test_subcommand_help():
    app, _ = make_app(deferred_help=False)

    # Help is called immediately
    with mock.patch('cliff.help.HelpAction.__call__') as helper:
        app.run(['show', 'files', '--help'])

    assert helper.called


def test_subcommand_deferred_help():
    app, _ = make_app(deferred_help=True)

    # Show that provide_help_if_requested() did not show help and exit
    with mock.patch.object(app, 'run_subcommand') as helper:
        app.run(['show', 'files', '--help'])

    helper.assert_called_once_with(['help', 'show', 'files'])


def test_unknown_cmd():
    app, command = make_app()
    assert app.run(['hell']) == 2


def test_unknown_cmd_debug():
    app, command = make_app()
    try:
        app.run(['--debug', 'hell']) == 2
    except ValueError as err:
        assert "['hell']" in ('%s' % err)


def test_list_matching_commands():
    stdout = StringIO()
    app = App('testing', '1',
              utils.TestCommandManager(utils.TEST_NAMESPACE),
              stdout=stdout)
    app.NAME = 'test'
    try:
        assert app.run(['t']) == 2
    except SystemExit:
        pass
    output = stdout.getvalue()
    assert "test: 't' is not a test command. See 'test --help'." in output
    assert 'Did you mean one of these?' in output
    assert 'three word command\n  two words\n' in output


def test_fuzzy_no_commands():
    cmd_mgr = CommandManager('cliff.fuzzy')
    app = App('test', '1.0', cmd_mgr)
    cmd_mgr.commands = {}
    matches = app.get_fuzzy_matches('foo')
    assert matches == []


def test_fuzzy_common_prefix():
    # searched string is a prefix of all commands
    cmd_mgr = CommandManager('cliff.fuzzy')
    app = App('test', '1.0', cmd_mgr)
    cmd_mgr.commands = {}
    cmd_mgr.add_command('user list', utils.TestCommand)
    cmd_mgr.add_command('user show', utils.TestCommand)
    matches = app.get_fuzzy_matches('user')
    assert matches == ['user list', 'user show']


def test_fuzzy_same_distance():
    # searched string has the same distance to all commands
    cmd_mgr = CommandManager('cliff.fuzzy')
    app = App('test', '1.0', cmd_mgr)
    cmd_mgr.add_command('user', utils.TestCommand)
    for cmd in cmd_mgr.commands.keys():
        assert damerau_levenshtein('node', cmd, COST) == 8
    matches = app.get_fuzzy_matches('node')
    assert matches == ['complete', 'help', 'user']


def test_fuzzy_no_prefix():
    # search by distance, no common prefix with any command
    cmd_mgr = CommandManager('cliff.fuzzy')
    app = App('test', '1.0', cmd_mgr)
    cmd_mgr.add_command('user', utils.TestCommand)
    matches = app.get_fuzzy_matches('uesr')
    assert matches == ['user']


def test_verbose():
    app, command = make_app()
    app.clean_up = mock.MagicMock(name='clean_up')
    app.run(['--verbose', 'mock'])
    app.clean_up.assert_called_once_with(command.return_value, 0, None)
    app.clean_up.reset_mock()
    app.run(['--quiet', 'mock'])
    app.clean_up.assert_called_once_with(command.return_value, 0, None)
    try:
        app.run(['--verbose', '--quiet', 'mock'])
    except SystemExit:
        pass
    else:
        raise Exception('Exception was not thrown')
