# (c) 2017 Ansible By Red Hat
#
# This file is part of Ansible
#
# Ansible is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# Ansible is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with Ansible.  If not, see <http://www.gnu.org/licenses/>.

# Make coding more python3-ish
from __future__ import (absolute_import, division, print_function)
__metaclass__ = type

from ansible.playbook import Play
from ansible.playbook.block import Block
from ansible.playbook.role import Role
from ansible.playbook.task import Task

try:
    from __main__ import display
except ImportError:
    from ansible.utils.display import Display
    display = Display()


def get_reserved_names(include_private=True):
    ''' this function returns the list of reserved names associated with play objects'''

    public = set()
    private = set()
    result = set()

    # FIXME: find a way to 'not hardcode', possibly need role deps/includes
    class_list = [Play, Role, Block, Task]

    for aclass in class_list:
        aobj = aclass()

        # build ordered list to loop over and dict with attributes
        for attribute in aobj.__dict__['_attributes']:
            if 'private' in attribute:
                private.add(attribute)
            else:
                public.add(attribute)

    # local_action is implicit with action
    if 'action' in public:
        public.add('local_action')

    # loop implies with_
    # FIXME: remove after with_ is not only deprecated but removed
    if 'loop' in private or 'loop' in public:
        public.add('with_')

    if include_private:
        result = public.union(private)
    else:
        result = public

    return result


def warn_if_reserved(myvars):
    ''' this function warns if any variable passed conflicts with internally reserved names '''

    varnames = set(myvars)
    varnames.discard('vars')  # we add this one internally, so safe to ignore
    for varname in varnames.intersection(_RESERVED_NAMES):
        display.warning('Found variable using reserved name: %s' % varname)


_RESERVED_NAMES = frozenset(get_reserved_names())
