text: # Copyright: (c) 2012-2014, Michael DeHaan <michael.dehaan@gmail.com>
  # Copyright: (c) 2017, Ansible Project
  # GNU General Public License v3.0+ (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
  
  from __future__ import (absolute_import, division, print_function)
  __metaclass__ = type
  
  import os
  import re
  
  from ast import literal_eval
  from jinja2 import Template
  from string import ascii_letters, digits
  
  from ansible.config.manager import ConfigManager, ensure_type, get_ini_config_value
  from ansible.module_utils._text import to_text
  from ansible.module_utils.common.collections import Sequence
  from ansible.module_utils.parsing.convert_bool import boolean, BOOLEANS_TRUE
  from ansible.module_utils.six import string_types
  from ansible.utils.fqcn import add_internal_fqcns
  
  
  def _warning(msg):
      ''' display is not guaranteed here, nor it being the full class, but try anyways, fallback to sys.stderr.write '''
      try:
          from ansible.utils.display import Display
          Display().warning(msg)
      except Exception:
          import sys
          sys.stderr.write(' [WARNING] %s\n' % (msg))
  
  
  def _deprecated(msg, version='2.8'):
      ''' display is not guaranteed here, nor it being the full class, but try anyways, fallback to sys.stderr.write '''
      try:
          from ansible.utils.display import Display
          Display().deprecated(msg, version=version)
      except Exception:
          import sys
          sys.stderr.write(' [DEPRECATED] %s, to be removed in %s\n' % (msg, version))
  
  
  def mk_boolean(value):
      ''' moved to module_utils'''
      _deprecated('ansible.constants.mk_boolean() is deprecated.  Use ansible.module_utils.parsing.convert_bool.boolean() instead')
      return boolean(value, strict=False)
  
  
  def get_config(parser, section, key, env_var, default_value, value_type=None, expand_relative_paths=False):
      ''' kept for backwarsd compatibility, but deprecated '''
      _deprecated('ansible.constants.get_config() is deprecated. There is new config API, see porting docs.')
  
      value = None
      # small reconstruction of the old code env/ini/default
      value = os.environ.get(env_var, None)
      if value is None:
          try:
              value = get_ini_config_value(parser, {'key': key, 'section': section})
          except Exception:
              pass
      if value is None:
          value = default_value
  
      value = ensure_type(value, value_type)
  
      return value
  
  
  def set_constant(name, value, export=vars()):
      ''' sets constants and returns resolved options dict '''
      export[name] = value
  
  
  class _DeprecatedSequenceConstant(Sequence):
      def __init__(self, value, msg, version):
          self._value = value
          self._msg = msg
          self._version = version
  
      def __len__(self):
          _deprecated(self._msg, version=self._version)
          return len(self._value)
  
      def __getitem__(self, y):
          _deprecated(self._msg, version=self._version)
          return self._value[y]
  
  
  # Deprecated constants
  BECOME_METHODS = _DeprecatedSequenceConstant(
      ['sudo', 'su', 'pbrun', 'pfexec', 'doas', 'dzdo', 'ksu', 'runas', 'pmrun', 'enable', 'machinectl'],
      ('ansible.constants.BECOME_METHODS is deprecated, please use '
       'ansible.plugins.loader.become_loader. This list is statically '
       'defined and may not include all become methods'),
      '2.10'
  )
  
  # CONSTANTS ### yes, actual ones
  BLACKLIST_EXTS = ('.pyc', '.pyo', '.swp', '.bak', '~', '.rpm', '.md', '.txt', '.rst')
  BOOL_TRUE = BOOLEANS_TRUE
  COLLECTION_PTYPE_COMPAT = {'module': 'modules'}
  DEFAULT_BECOME_PASS = None
  DEFAULT_PASSWORD_CHARS = to_text(ascii_letters + digits + ".,:-_", errors='strict')  # characters included in auto-generated passwords
  DEFAULT_REMOTE_PASS = None
  DEFAULT_SUBSET = None
  # FIXME: expand to other plugins, but never doc fragments
  CONFIGURABLE_PLUGINS = ('become', 'cache', 'callback', 'cliconf', 'connection', 'httpapi', 'inventory', 'lookup', 'netconf', 'shell', 'vars')
  # NOTE: always update the docs/docsite/Makefile to match
  DOCUMENTABLE_PLUGINS = CONFIGURABLE_PLUGINS + ('module', 'strategy')
  IGNORE_FILES = ("COPYING", "CONTRIBUTING", "LICENSE", "README", "VERSION", "GUIDELINES")  # ignore during module search
  INTERNAL_RESULT_KEYS = ('add_host', 'add_group')
  LOCALHOST = ('127.0.0.1', 'localhost', '::1')
  MODULE_REQUIRE_ARGS = tuple(add_internal_fqcns(('command', 'win_command', 'ansible.windows.win_command', 'shell', 'win_shell',
                                                  'ansible.windows.win_shell', 'raw', 'script')))
  MODULE_NO_JSON = tuple(add_internal_fqcns(('command', 'win_command', 'ansible.windows.win_command', 'shell', 'win_shell',
                                             'ansible.windows.win_shell', 'raw')))
  RESTRICTED_RESULT_KEYS = ('ansible_rsync_path', 'ansible_playbook_python', 'ansible_facts')
  TREE_DIR = None
  VAULT_VERSION_MIN = 1.0
  VAULT_VERSION_MAX = 1.0
  
  # This matches a string that cannot be used as a valid python variable name i.e 'not-valid', 'not!valid@either' '1_nor_This'
  INVALID_VARIABLE_NAMES = re.compile(r'^[\d\W]|[^\w]')
  
  
  # FIXME: remove once play_context mangling is removed
  # the magic variable mapping dictionary below is used to translate
  # host/inventory variables to fields in the PlayContext
  # object. The dictionary values are tuples, to account for aliases
  # in variable names.
  
  COMMON_CONNECTION_VARS = frozenset(('ansible_connection', 'ansible_host', 'ansible_user', 'ansible_shell_executable',
                                      'ansible_port', 'ansible_pipelining', 'ansible_password', 'ansible_timeout',
                                      'ansible_shell_type', 'ansible_module_compression', 'ansible_private_key_file'))
  
  MAGIC_VARIABLE_MAPPING = dict(
  
      # base
      connection=('ansible_connection', ),
      module_compression=('ansible_module_compression', ),
      shell=('ansible_shell_type', ),
      executable=('ansible_shell_executable', ),
  
      # connection common
      remote_addr=('ansible_ssh_host', 'ansible_host'),
      remote_user=('ansible_ssh_user', 'ansible_user'),
      password=('ansible_ssh_pass', 'ansible_password'),
      port=('ansible_ssh_port', 'ansible_port'),
      pipelining=('ansible_ssh_pipelining', 'ansible_pipelining'),
      timeout=('ansible_ssh_timeout', 'ansible_timeout'),
      private_key_file=('ansible_ssh_private_key_file', 'ansible_private_key_file'),
  
      # networking modules
      network_os=('ansible_network_os', ),
      connection_user=('ansible_connection_user',),
  
      # ssh TODO: remove
      ssh_executable=('ansible_ssh_executable', ),
      ssh_common_args=('ansible_ssh_common_args', ),
      sftp_extra_args=('ansible_sftp_extra_args', ),
      scp_extra_args=('ansible_scp_extra_args', ),
      ssh_extra_args=('ansible_ssh_extra_args', ),
      ssh_transfer_method=('ansible_ssh_transfer_method', ),
  
      # docker TODO: remove
      docker_extra_args=('ansible_docker_extra_args', ),
  
      # become
      become=('ansible_become', ),
      become_method=('ansible_become_method', ),
      become_user=('ansible_become_user', ),
      become_pass=('ansible_become_password', 'ansible_become_pass'),
      become_exe=('ansible_become_exe', ),
      become_flags=('ansible_become_flags', ),
  )
  
  # POPULATE SETTINGS FROM CONFIG ###
  config = ConfigManager()
  
  # Generate constants from config
  for setting in config.data.get_settings():
  
      value = setting.value
      if setting.origin == 'default' and \
         isinstance(setting.value, string_types) and \
         (setting.value.startswith('{{') and setting.value.endswith('}}')):
          try:
              t = Template(setting.value)
              value = t.render(vars())
              try:
                  value = literal_eval(value)
              except ValueError:
                  pass  # not a python data structure
          except Exception:
              pass  # not templatable
  
          value = ensure_type(value, setting.type)
  
      set_constant(setting.name, value)
  
  for warn in config.WARNINGS:
      _warning(warn)
  
  
  # The following are hard-coded action names
  _ACTION_DEBUG = add_internal_fqcns(('debug', ))
  _ACTION_IMPORT_PLAYBOOK = add_internal_fqcns(('import_playbook', ))
  _ACTION_IMPORT_ROLE = add_internal_fqcns(('import_role', ))
  _ACTION_IMPORT_TASKS = add_internal_fqcns(('import_tasks', ))
  _ACTION_INCLUDE = add_internal_fqcns(('include', ))
  _ACTION_INCLUDE_ROLE = add_internal_fqcns(('include_role', ))
  _ACTION_INCLUDE_TASKS = add_internal_fqcns(('include_tasks', ))
  _ACTION_INCLUDE_VARS = add_internal_fqcns(('include_vars', ))
  _ACTION_META = add_internal_fqcns(('meta', ))
  _ACTION_SET_FACT = add_internal_fqcns(('set_fact', ))
  _ACTION_SETUP = add_internal_fqcns(('setup', ))
  _ACTION_HAS_CMD = add_internal_fqcns(('command', 'shell', 'script'))
  _ACTION_ALLOWS_RAW_ARGS = _ACTION_HAS_CMD + add_internal_fqcns(('raw', ))
  _ACTION_ALL_INCLUDES = _ACTION_INCLUDE + _ACTION_INCLUDE_TASKS + _ACTION_INCLUDE_ROLE
  _ACTION_ALL_IMPORT_PLAYBOOKS = _ACTION_INCLUDE + _ACTION_IMPORT_PLAYBOOK
  _ACTION_ALL_INCLUDE_IMPORT_TASKS = _ACTION_INCLUDE + _ACTION_INCLUDE_TASKS + _ACTION_IMPORT_TASKS
  _ACTION_ALL_PROPER_INCLUDE_IMPORT_ROLES = _ACTION_INCLUDE_ROLE + _ACTION_IMPORT_ROLE
  _ACTION_ALL_PROPER_INCLUDE_IMPORT_TASKS = _ACTION_INCLUDE_TASKS + _ACTION_IMPORT_TASKS
  _ACTION_ALL_INCLUDE_ROLE_TASKS = _ACTION_INCLUDE_ROLE + _ACTION_INCLUDE_TASKS
  _ACTION_ALL_INCLUDE_TASKS = _ACTION_INCLUDE + _ACTION_INCLUDE_TASKS
  _ACTION_FACT_GATHERING = _ACTION_SETUP + add_internal_fqcns(('gather_facts', ))
  _ACTION_WITH_CLEAN_FACTS = _ACTION_SET_FACT + _ACTION_INCLUDE_VARS
  