# (C) 2017 Red Hat Inc.
# Copyright (C) 2017 Lenovo.
#
# GNU General Public License v3.0+
#
# This program 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.
#
# (see COPYING or https://www.gnu.org/licenses/gpl-3.0.txt)
#
# Contains terminal Plugin methods for CNOS Config Module
# Lenovo Networking
#
from __future__ import (absolute_import, division, print_function)
__metaclass__ = type

import json
import re

from ansible.errors import AnsibleConnectionFailure
from ansible.module_utils._text import to_text, to_bytes
from ansible.plugins.terminal import TerminalBase


class TerminalModule(TerminalBase):

    terminal_stdout_re = [
        re.compile(br"[\r\n]?[\w+\-\.:\/\[\]]+(?:\([^\)]+\)){,3}(?:>|#) ?$"),
        re.compile(br"\[\w+\@[\w\-\.]+(?: [^\]])\] ?[>#\$] ?$"),
        re.compile(br">[\r\n]?")
    ]

    terminal_stderr_re = [
        re.compile(br"% ?Error"),
        re.compile(br"% ?Bad secret"),
        re.compile(br"invalid input", re.I),
        re.compile(br"(?:incomplete|ambiguous) command", re.I),
        re.compile(br"connection timed out", re.I),
        re.compile(br"[^\r\n]+ not found"),
        re.compile(br"'[^']' +returned error code: ?\d+"),
    ]

    def on_open_shell(self):
        try:
            for cmd in (b'\n', b'terminal length 0\n'):
                self._exec_cli_command(cmd)
        except AnsibleConnectionFailure:
            raise AnsibleConnectionFailure('unable to set terminal parameters')

    def on_become(self, passwd=None):
        if self._get_prompt().endswith(b'#'):
            return

        cmd = {u'command': u'enable'}
        if passwd:
            # Note: python-3.5 cannot combine u"" and r"" together.  Thus make
            # an r string and use to_text to ensure it's text
            # on both py2 and py3.
            cmd[u'prompt'] = to_text(r"[\r\n]?password: $",
                                     errors='surrogate_or_strict')
            cmd[u'answer'] = passwd

        try:
            self._exec_cli_command(to_bytes(json.dumps(cmd),
                                   errors='surrogate_or_strict'))
        except AnsibleConnectionFailure:
            msg = 'unable to elevate privilege to enable mode'
            raise AnsibleConnectionFailure(msg)

    def on_unbecome(self):
        prompt = self._get_prompt()
        if prompt is None:
            # if prompt is None most likely the terminal is hung up at a prompt
            return

        if b'(config' in prompt:
            self._exec_cli_command(b'end')
            self._exec_cli_command(b'disable')

        elif prompt.endswith(b'#'):
            self._exec_cli_command(b'disable')