from __future__ import print_function

import pytest

from face import (Flag,
                  ERROR,
                  Command,
                  CommandChecker,
                  Parser,
                  PosArgSpec,
                  HelpHandler,
                  ArgumentParseError,
                  StoutHelpFormatter)
from face.utils import format_flag_post_doc


def get_subcmd_cmd():
    subcmd = Command(None, name='subcmd', doc='the subcmd help')
    subcmd.add(_subsubcmd, name='subsubcmd', posargs={'count': 2, 'name': 'posarg_item'})
    cmd = Command(None, 'halp', doc='halp help')
    cmd.add(subcmd)

    return cmd


def _subsubcmd():
    """the subsubcmd help

    another line
    """
    pass


@pytest.fixture
def subcmd_cmd():
    return get_subcmd_cmd()


@pytest.mark.parametrize(
    "argv, contains, exit_code",
    [(['halp', '-h'], ['Usage', 'halp help', 'subcmd'], 0),  # basic, explicit help
     (['halp', '--help'], ['Usage', 'halp help', 'subcmd'], 0),
     # explicit help on subcommands
     (['halp', 'subcmd', '-h'], ['Usage', 'the subcmd help', 'subsubcmd'], 0),
     (['halp', 'subcmd', 'subsubcmd', '-h'], ['Usage', 'the subsubcmd help', 'posarg_item'], 0),
     # invalid subcommands
     # TODO: the following should also include "nonexistent-subcmd" but instead it lists "nonexistent_subcmd"
     (['halp', 'nonexistent-subcmd'], ['error', 'subcmd'], 1),
     (['halp', 'subcmd', 'nonexistent-subsubcmd'], ['error', 'subsubcmd'], 1)
     ]
)
def test_help(subcmd_cmd, argv, contains, exit_code, capsys):
    if isinstance(contains, str):
        contains = [contains]

    try:
        subcmd_cmd.run(argv)
    except SystemExit as se:
        if exit_code is not None:
            assert se.code == exit_code

    out, err = capsys.readouterr()
    if exit_code == 0:
        output = out
    else:
        output = err

    for cont in contains:
        assert cont in output

    return


def test_help_subcmd():
    hhandler = HelpHandler(flag=False, subcmd='help')
    cmd = Command(None, 'cmd', help=hhandler)

    try:
        cmd.run(['cmd', 'help'])
    except SystemExit as se:
        assert se.code == 0

    with pytest.raises(ValueError, match='requires a handler function or help handler'):
        Command(None, help=None)


def test_err_subcmd_prog_name():
    cmd = Command(lambda: print("foo"), "foo")
    subcmd = Command(lambda: print("bar"), "bar")
    subcmd.add(Command(lambda: print("baz"), "baz"))
    cmd.add(subcmd)

    cc = CommandChecker(cmd)
    res = cc.fail('fred.py bar ba')
    assert 'fred.py' in res.stderr
    assert 'foo' not in res.stderr


def test_stout_help():
    with pytest.raises(TypeError, match='unexpected formatter arguments'):
        StoutHelpFormatter(bad_kwarg=True)

    return


def test_handler():
    with pytest.raises(TypeError, match='expected help handler func to be callable'):
        HelpHandler(func=object())

    with pytest.raises(TypeError, match='expected Formatter type or instance'):
        HelpHandler(formatter=None)

    with pytest.raises(TypeError, match='only accepts extra formatter'):
        HelpHandler(usage_label='Fun: ', formatter=StoutHelpFormatter())

    with pytest.raises(TypeError, match='expected valid formatter'):
        HelpHandler(formatter=object())



# TODO: need to have commands reload their own subcommands if
# we're going to allow adding subcommands to subcommands after
# initial addition to the parent command


def test_flag_post_doc():
    assert format_flag_post_doc(Flag('flag')) == ''
    assert format_flag_post_doc(Flag('flag', missing=42)) == '(defaults to 42)'
    assert format_flag_post_doc(Flag('flag', missing=ERROR)) == '(required)'
    assert format_flag_post_doc(Flag('flag', display={'post_doc': '(fun)'})) == '(fun)'