"""
    sphinxcontrib.autoprogram
    ~~~~~~~~~~~~~~~~~~~~~~~~~

    Documenting CLI programs.

    :copyright: Copyright 2014 by Hong Minhee
    :license: BSD, see LICENSE for details.

"""
# pylint: disable=protected-access,missing-docstring
import argparse
import collections
try:
    import builtins
except ImportError:
    import __builtin__ as builtins
import functools
import re
import unittest
import six

from docutils import nodes
from docutils.parsers.rst.directives import unchanged
from docutils.statemachine import ViewList
from sphinx.util.compat import Directive
from sphinx.util.nodes import nested_parse_with_titles
from sphinx.domains import std

__all__ = ('BOOLEAN_OPTIONS', 'AutoprogramDirective', 'ScannerTestCase',
           'import_object', 'scan_programs', 'setup', 'suite')


def scan_programs(parser, command=[]):
    options = []
    for arg in parser._actions:
        if not (arg.option_strings or
                isinstance(arg, argparse._SubParsersAction)):
            name = (arg.metavar or arg.dest).lower()
            desc = (arg.help or '') % {'default': arg.default}
            options.append(([name], desc))
    for arg in parser._actions:
        if arg.option_strings:
            if isinstance(arg, (argparse._StoreAction,
                                argparse._AppendAction)):
                if arg.choices is None:
                    metavar = (arg.metavar or arg.dest).lower()
                    names = ['{0} <{1}>'.format(option_string, metavar)
                             for option_string in arg.option_strings]
                else:
                    choices = '{0}'.format(','.join(arg.choices))
                    names = ['{0} {{{1}}}'.format(option_string, choices)
                             for option_string in arg.option_strings]
            else:
                names = list(arg.option_strings)
            desc = (arg.help or '') % {'default': arg.default}
            options.append((names, desc))
    yield command, options, parser.description, parser.epilog or ''
    if parser._subparsers:
        choices = parser._subparsers._actions[-1].choices.items()
        if not (hasattr(collections, 'OrderedDict') and
                isinstance(choices, collections.OrderedDict)):
            choices = sorted(choices, key=lambda pair: pair[0])
        for cmd, sub in choices:
            if isinstance(sub, argparse.ArgumentParser):
                for program in scan_programs(sub, command + [cmd]):
                    yield program


def import_object(import_name):
    module_name, expr = import_name.split(':', 1)
    try:
        mod = __import__(module_name)
    except ImportError:
        # This happens if the file is a script with no .py extension. Here we
        # trick autoprogram to load a module in memory with the contents of
        # the script, if there is a script named module_name. Otherwise, raise
        # an ImportError as it did before.
        import glob
        import sys
        import os
        import imp

        for p in sys.path:
            f = glob.glob(os.path.join(p, module_name))
            if len(f) > 0:
                with open(f[0]) as fobj:
                    codestring = fobj.read()
                foo = imp.new_module("foo")
                six.exec_(codestring, foo.__dict__)

                sys.modules["foo"] = foo
                mod = __import__("foo")
                break
        else:
            raise ImportError("No module named {}".format(module_name))

    reduce_ = getattr(functools, 'reduce', None) or reduce
    mod = reduce_(getattr, module_name.split('.')[1:], mod)
    globals_ = builtins
    if not isinstance(globals_, dict):
        globals_ = globals_.__dict__
    return eval(expr, globals_, mod.__dict__)


class AutoprogramDirective(Directive):

    has_content = False
    required_arguments = 1
    option_spec = {'prog': unchanged}

    def make_rst(self):
        import_name, = self.arguments
        parser = import_object(import_name or '__undefined__')
        parser.prog = self.options.get('prog', parser.prog)
        for commands, options, desc, epilog in scan_programs(parser):
            command = ' '.join(commands)
            title = '{0} {1}'.format(parser.prog, command).rstrip()
            yield ''
            yield '.. program:: ' + title
            yield ''
            yield title
            yield ('!' if commands else '?') * len(title)
            yield ''
            yield desc or ''
            yield ''
            yield parser.format_usage()
            yield ''
            for option_strings, help_ in options:
                yield '.. option:: {0}'.format(', '.join(option_strings))
                yield ''
                yield '   ' + help_.replace('\n', '   \n')
                yield ''
            yield ''
            for line in epilog.splitlines():
                yield line or ''

    def run(self):
        node = nodes.section()
        node.document = self.state.document
        result = ViewList()
        for line in self.make_rst():
            result.append(line, '<autoprogram>')
        nested_parse_with_titles(self.state, result, node)
        return node.children


def patch_option_role_to_allow_argument_form():
    """Before Sphinx 1.2.2, :rst:dir:`.. option::` directive hadn't
    allowed to not start with a dash or slash, so it hadn't been possible
    to represent positional arguments (not options).

    https://bitbucket.org/birkenfeld/sphinx/issue/1357/

    It monkeypatches the :rst:dir:`.. option::` directive's behavior.

    """
    std.option_desc_re = re.compile(r'((?:/|-|--)?[-_a-zA-Z0-9]+)(\s*.*)')


def setup(app):
    app.add_directive('autoprogram', AutoprogramDirective)
    patch_option_role_to_allow_argument_form()


class ScannerTestCase(unittest.TestCase):

    def test_simple_parser(self):
        parser = argparse.ArgumentParser(description='Process some integers.')
        parser.add_argument('integers', metavar='N', type=int, nargs='*',
                            help='an integer for the accumulator')
        parser.add_argument('-i', '--identity', type=int, default=0,
                            help='the default result for no arguments '
                                 '(default: 0)')
        parser.add_argument('--sum', dest='accumulate', action='store_const',
                            const=sum, default=max,
                            help='sum the integers (default: find the max)')
        programs = scan_programs(parser)
        programs = list(programs)
        self.assertEqual(1, len(programs))
        parser_info, = programs
        program, options, desc, _ = parser_info
        self.assertEqual([], program)
        self.assertEqual('Process some integers.', desc)
        self.assertEqual(4, len(options))
        self.assertEqual(
            (['n'], 'an integer for the accumulator'),
            options[0]
        )
        self.assertEqual(
            (['-h', '--help'], 'show this help message and exit'),
            options[1]
        )
        self.assertEqual(
            (['-i <identity>', '--identity <identity>'],
             'the default result for no arguments (default: 0)'),
            options[2]
        )
        self.assertEqual(
            (['--sum'], 'sum the integers (default: find the max)'),
            options[3]
        )

    def test_subcommands(self):
        parser = argparse.ArgumentParser(description='Process some integers.')
        subparsers = parser.add_subparsers()
        max_parser = subparsers.add_parser('max', description='Find the max.')
        max_parser.set_defaults(accumulate=max)
        max_parser.add_argument('integers', metavar='N', type=int, nargs='+',
                                help='An integer for the accumulator.')
        sum_parser = subparsers.add_parser('sum',
                                           description='Sum the integers.')
        sum_parser.set_defaults(accumulate=sum)
        sum_parser.add_argument('integers', metavar='N', type=int, nargs='+',
                                help='An integer for the accumulator.')
        programs = scan_programs(parser)
        programs = list(programs)
        self.assertEqual(3, len(programs))
        # main
        program, options, desc, _ = programs[0]
        self.assertEqual([], program)
        self.assertEqual('Process some integers.', desc)
        self.assertEqual(1, len(options))
        self.assertEqual(
            (['-h', '--help'],
             'show this help message and exit'),
            options[0]
        )
        # max
        program, options, desc, _ = programs[1]
        self.assertEqual(['max'], program)
        self.assertEqual('Find the max.', desc)
        self.assertEqual(2, len(options))
        self.assertEqual((['n'], 'An integer for the accumulator.'),
                         options[0])
        self.assertEqual(
            (['-h', '--help'],
             'show this help message and exit'),
            options[1]
        )
        # sum
        program, options, desc, _ = programs[2]
        self.assertEqual(['sum'], program)
        self.assertEqual('Sum the integers.', desc)
        self.assertEqual(2, len(options))
        self.assertEqual((['n'], 'An integer for the accumulator.'),
                         options[0])

    def test_choices(self):
        parser = argparse.ArgumentParser()
        parser.add_argument("--awesomeness", choices=["meh", "awesome"])
        program, options, desc, _ = list(scan_programs(parser))[0]
        log_option = options[1]
        self.assertEqual((["--awesomeness {meh,awesome}"], ''), log_option)

    def test_parse_epilog(self):
        parser = argparse.ArgumentParser(
            description='Process some integers.',
            epilog='The integers will be processed.'
        )
        programs = scan_programs(parser)
        programs = list(programs)
        self.assertEqual(1, len(programs))
        parser_data, = programs
        program, options, desc, epilog = parser_data
        self.assertEqual('The integers will be processed.', epilog)


class UtilTestCase(unittest.TestCase):

    def test_import_object(self):
        cls = import_object('sphinxcontrib.autoprogram:UtilTestCase')
        self.assertTrue(cls is UtilTestCase)
        instance = import_object(
            'sphinxcontrib.autoprogram:UtilTestCase("test_import_object")'
        )
        self.assertIsInstance(instance, UtilTestCase)

    if not hasattr(unittest.TestCase, 'assertIsInstance'):
        def assertIsInstance(self, instance, cls):
            self.assertTrue(isinstance(instance, cls),
                            '{0!r} is not an instance of {1.__module__}.'
                            '{1.__name__}'.format(instance, cls))


suite = unittest.TestSuite()
suite.addTests(
    unittest.defaultTestLoader.loadTestsFromTestCase(ScannerTestCase)
)
suite.addTests(unittest.defaultTestLoader.loadTestsFromTestCase(UtilTestCase))
