# Copyright (c) 2015 Ansible, Inc.
# All Rights Reserved.
from __future__ import absolute_import, unicode_literals

import os
import sys
import warnings

from pkg_resources import get_distribution

__version__ = get_distribution('awx').version
__all__ = ['__version__']


# Check for the presence/absence of "devonly" module to determine if running
# from a source code checkout or release packaage.
try:
    import awx.devonly # noqa
    MODE = 'development'
except ImportError: # pragma: no cover
    MODE = 'production'


import hashlib

try:
    import django
    from django.db.backends.base import schema
    from django.db.backends.utils import names_digest
    HAS_DJANGO = True
except ImportError:
    HAS_DJANGO = False


if HAS_DJANGO is True:
    # This line exists to make sure we don't regress on FIPS support if we
    # upgrade Django; if you're upgrading Django and see this error,
    # update the version check below, and confirm that FIPS still works.
    # If operating in a FIPS environment, `hashlib.md5()` will raise a `ValueError`,
    # but will support the `usedforsecurity` keyword on RHEL and Centos systems.

    # Keep an eye on https://code.djangoproject.com/ticket/28401
    target_version = '2.2.2'
    if django.__version__ != target_version:
        raise RuntimeError(
            "Django version other than {target} detected: {current}. "
            "Overriding `names_digest` is known to work for Django {target} "
            "and may not work in other Django versions.".format(target=target_version,
                                                                current=django.__version__)
        )

    try:
        names_digest('foo', 'bar', 'baz', length=8)
    except ValueError:
        def names_digest(*args, length):
            """
            Generate a 32-bit digest of a set of arguments that can be used to shorten
            identifying names.  Support for use in FIPS environments.
            """
            h = hashlib.md5(usedforsecurity=False)
            for arg in args:
                h.update(arg.encode())
            return h.hexdigest()[:length]

        schema.names_digest = names_digest


def find_commands(management_dir):
    # Modified version of function from django/core/management/__init__.py.
    command_dir = os.path.join(management_dir, 'commands')
    commands = []
    try:
        for f in os.listdir(command_dir):
            if f.startswith('_'):
                continue
            elif f.endswith('.py') and f[:-3] not in commands:
                commands.append(f[:-3])
            elif f.endswith('.pyc') and f[:-4] not in commands: # pragma: no cover
                commands.append(f[:-4])
    except OSError:
        pass
    return commands


def prepare_env():
    # Update the default settings environment variable based on current mode.
    os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'awx.settings.%s' % MODE)
    # Hide DeprecationWarnings when running in production.  Need to first load
    # settings to apply our filter after Django's own warnings filter.
    from django.conf import settings
    if not settings.DEBUG: # pragma: no cover
        warnings.simplefilter('ignore', DeprecationWarning)
    # Monkeypatch Django find_commands to also work with .pyc files.
    import django.core.management
    django.core.management.find_commands = find_commands
    # Use the AWX_TEST_DATABASE_* environment variables to specify the test
    # database settings to use when management command is run as an external
    # program via unit tests.
    for opt in ('ENGINE', 'NAME', 'USER', 'PASSWORD', 'HOST', 'PORT'): # pragma: no cover
        if os.environ.get('AWX_TEST_DATABASE_%s' % opt, None):
            settings.DATABASES['default'][opt] = os.environ['AWX_TEST_DATABASE_%s' % opt]
    # Disable capturing all SQL queries in memory when in DEBUG mode.
    if settings.DEBUG and not getattr(settings, 'SQL_DEBUG', True):
        from django.db.backends.base.base import BaseDatabaseWrapper
        from django.db.backends.utils import CursorWrapper
        BaseDatabaseWrapper.make_debug_cursor = lambda self, cursor: CursorWrapper(cursor, self)

    # Use the default devserver addr/port defined in settings for runserver.
    default_addr = getattr(settings, 'DEVSERVER_DEFAULT_ADDR', '127.0.0.1')
    default_port = getattr(settings, 'DEVSERVER_DEFAULT_PORT', 8000)
    from django.core.management.commands import runserver as core_runserver
    original_handle = core_runserver.Command.handle

    def handle(self, *args, **options):
        if not options.get('addrport'):
            options['addrport'] = '%s:%d' % (default_addr, int(default_port))
        elif options.get('addrport').isdigit():
            options['addrport'] = '%s:%d' % (default_addr, int(options['addrport']))
        return original_handle(self, *args, **options)

    core_runserver.Command.handle = handle


def manage():
    # Prepare the AWX environment.
    prepare_env()
    # Now run the command (or display the version).
    from django.conf import settings
    from django.core.management import execute_from_command_line
    if len(sys.argv) >= 2 and sys.argv[1] in ('version', '--version'): # pragma: no cover
        sys.stdout.write('%s\n' % __version__)
    # If running as a user without permission to read settings, display an
    # error message.  Allow --help to still work.
    elif settings.SECRET_KEY == 'permission-denied':
        if len(sys.argv) == 1 or len(sys.argv) >= 2 and sys.argv[1] in ('-h', '--help', 'help'):
            execute_from_command_line(sys.argv)
            sys.stdout.write('\n')
        prog = os.path.basename(sys.argv[0])
        sys.stdout.write('Permission denied: %s must be run as root or awx.\n' % prog)
        sys.exit(1)
    else:
        execute_from_command_line(sys.argv)