# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

import functools
import pprint

from testinfra.modules.base import InstanceModule


class AnsibleException(Exception):
    """Exception raised when an error occur in an ansible call

    result from ansible can be accessed through the ``result`` attribute

    >>> try:
    ...     host.ansible("command", "echo foo")
    ... except host.ansible.AnsibleException as exc:
    ...     assert exc.result['failed'] is True
    ...     assert exc.result['msg'] == 'Skipped. You might want to try check=False'  # noqa
    """

    def __init__(self, result):
        self.result = result
        super().__init__("Unexpected error: {}".format(pprint.pformat(result)))


def need_ansible(func):
    @functools.wraps(func)
    def wrapper(self, *args, **kwargs):
        if not self._host.backend.HAS_RUN_ANSIBLE:
            raise RuntimeError((
                "Ansible module is only available with ansible "
                "connection backend"))
        return func(self, *args, **kwargs)
    return wrapper


class Ansible(InstanceModule):
    """Run Ansible module functions

    This module is only available with the :ref:`ansible connection
    backend` connection backend.

    `Check mode
    <https://docs.ansible.com/ansible/playbooks_checkmode.html>`_ is
    enabled by default, you can disable it with `check=False`.

    `Become
    <https://docs.ansible.com/ansible/user_guide/become.html#id1>`_ is
    `False` by default. You can enable it with `become=True`.

    Ansible arguments that are not related to the Ansible inventory or
    connection (both managed by testinfra) are also accepted through keyword
    arguments:

        - ``become_method`` *str* sudo, su, doas, etc.
        - ``become_user`` *str* become this user.
        - ``diff`` *bool*: when changing (small) files and templates, show the
          differences in those files.
        - ``extra_vars`` *dict* serialized to a JSON string, passed to
          Ansible.
        - ``one_line`` *bool*: condense output.
        - ``user`` *str* connect as this user.
        - ``verbose`` *int* level of verbosity

    >>> host.ansible("apt", "name=nginx state=present")["changed"]
    False
    >>> host.ansible("apt", "name=nginx state=present", become=True)["changed"]
    False
    >>> host.ansible("command", "echo foo", check=False)["stdout"]
    'foo'
    >>> host.ansible("setup")["ansible_facts"]["ansible_lsb"]["codename"]
    'jessie'
    >>> host.ansible("file", "path=/etc/passwd")["mode"]
    '0640'
    >>> host.ansible(
    ... "command",
    ... "id --user --name",
    ... check=False,
    ... become=True,
    ... become_user="http",
    ... )["stdout"]
    'http'
    >>> host.ansible(
    ... "apt",
    ... "name={{ packages }}",
    ... check=False,
    ... extra_vars={"packages": ["neovim", "vim"]},
    ... )
    # Installs neovim and vim.

    """
    AnsibleException = AnsibleException

    @need_ansible
    def __call__(self, module_name, module_args=None, check=True,
                 become=False, **kwargs):
        result = self._host.backend.run_ansible(
            module_name, module_args, check=check, become=become, **kwargs)
        if result.get("failed", False):
            raise AnsibleException(result)
        return result

    @need_ansible
    def get_variables(self):
        """Returns a dict of ansible variables

        >>> host.ansible.get_variables()
        {
            'inventory_hostname': 'localhost',
            'group_names': ['ungrouped'],
            'foo': 'bar',
        }

        """
        return self._host.backend.get_variables()

    def __repr__(self):
        return "<ansible>"
