# This code is part of Ansible, but is an independent component.
# This particular file snippet, and this file snippet only, is BSD licensed.
# Modules you write using this snippet, which is embedded dynamically by
# Ansible still belong to the author of the module, and may assign their own
# license to the complete work.
#
# Copyright (C) 2017 Lenovo, Inc.
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
#  * Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
#  * Redistributions in binary form must reproduce the above copyright notice,
#    this list of conditions and the following disclaimer in the documentation
#    and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
# POSSIBILITY OF SUCH DAMAGE.
#
# Contains utility methods
# Lenovo Networking

from ansible.module_utils._text import to_text
from ansible.module_utils.basic import env_fallback, return_values
from ansible.module_utils.network.common.utils import to_list, EntityCollection
from ansible.module_utils.connection import Connection, exec_command
from ansible.module_utils.connection import ConnectionError

_DEVICE_CONFIGS = {}
_CONNECTION = None

enos_provider_spec = {
    'host': dict(),
    'port': dict(type='int'),
    'username': dict(fallback=(env_fallback, ['ANSIBLE_NET_USERNAME'])),
    'password': dict(fallback=(env_fallback, ['ANSIBLE_NET_PASSWORD']), no_log=True),
    'ssh_keyfile': dict(fallback=(env_fallback, ['ANSIBLE_NET_SSH_KEYFILE']), type='path'),
    'authorize': dict(fallback=(env_fallback, ['ANSIBLE_NET_AUTHORIZE']), type='bool'),
    'auth_pass': dict(fallback=(env_fallback, ['ANSIBLE_NET_AUTH_PASS']), no_log=True),
    'timeout': dict(type='int'),
    'context': dict(),
    'passwords': dict()
}

enos_argument_spec = {
    'provider': dict(type='dict', options=enos_provider_spec),
}

command_spec = {
    'command': dict(key=True),
    'prompt': dict(),
    'answer': dict()
}


def get_provider_argspec():
    return enos_provider_spec


def check_args(module, warnings):
    pass


def get_connection(module):
    global _CONNECTION
    if _CONNECTION:
        return _CONNECTION
    _CONNECTION = Connection(module._socket_path)

    context = None
    try:
        context = module.params['context']
    except KeyError:
        context = None

    if context:
        if context == 'system':
            command = 'changeto system'
        else:
            command = 'changeto context %s' % context
        _CONNECTION.get(command)

    return _CONNECTION


def get_config(module, flags=None):
    flags = [] if flags is None else flags

    passwords = None
    try:
        passwords = module.params['passwords']
    except KeyError:
        passwords = None
    if passwords:
        cmd = 'more system:running-config'
    else:
        cmd = 'show running-config '
        cmd += ' '.join(flags)
        cmd = cmd.strip()

    try:
        return _DEVICE_CONFIGS[cmd]
    except KeyError:
        conn = get_connection(module)
        out = conn.get(cmd)
        cfg = to_text(out, errors='surrogate_then_replace').strip()
        _DEVICE_CONFIGS[cmd] = cfg
        return cfg


def to_commands(module, commands):
    if not isinstance(commands, list):
        raise AssertionError('argument must be of type <list>')

    transform = EntityCollection(module, command_spec)
    commands = transform(commands)

    for index, item in enumerate(commands):
        if module.check_mode and not item['command'].startswith('show'):
            module.warn('only show commands are supported when using check '
                        'mode, not executing `%s`' % item['command'])

    return commands


def run_commands(module, commands, check_rc=True):
    connection = get_connection(module)

    commands = to_commands(module, to_list(commands))

    responses = list()

    for cmd in commands:
        out = connection.get(**cmd)
        responses.append(to_text(out, errors='surrogate_then_replace'))

    return responses


def load_config(module, config):
    try:
        conn = get_connection(module)
        conn.get('enable')
        conn.edit_config(config)
    except ConnectionError as exc:
        module.fail_json(msg=to_text(exc))


def get_defaults_flag(module):
    rc, out, err = exec_command(module, 'show running-config ?')
    out = to_text(out, errors='surrogate_then_replace')

    commands = set()
    for line in out.splitlines():
        if line:
            commands.add(line.strip().split()[0])

    if 'all' in commands:
        return 'all'
    else:
        return 'full'
