"""
Management of MySQL users
=========================

:depends:   - MySQLdb Python module
:configuration: See :py:mod:`salt.modules.mysql` for setup instructions.

.. code-block:: yaml

    frank:
      mysql_user.present:
        - host: localhost
        - password: bobcat


.. versionadded:: 0.16.2
    Authentication overrides have been added.

The MySQL authentication information specified in the minion config file can be
overridden in states using the following arguments: ``connection_host``,
``connection_port``, ``connection_user``, ``connection_pass``,
``connection_db``, ``connection_unix_socket``, ``connection_default_file`` and
``connection_charset``.

.. code-block:: yaml

    frank:
      mysql_user.present:
        - host: localhost
        - password: "bob@cat"
        - connection_user: someuser
        - connection_pass: somepass
        - connection_charset: utf8
        - saltenv:
          - LC_ALL: "en_US.utf8"


This state is not able to grant permissions for the user. See
:py:mod:`salt.states.mysql_grants` for further instructions.

"""

import sys

import salt.utils.data


def __virtual__():
    """
    Only load if the mysql module is in __salt__
    """
    if "mysql.user_create" in __salt__:
        return True
    return (False, "mysql module could not be loaded")


def _get_mysql_error():
    """
    Look in module context for a MySQL error. Eventually we should make a less
    ugly way of doing this.
    """
    return sys.modules[__salt__["test.ping"].__module__].__context__.pop(
        "mysql.error", None
    )


def present(
    name,
    host="localhost",
    password=None,
    password_hash=None,
    allow_passwordless=False,
    unix_socket=False,
    password_column=None,
    auth_plugin="mysql_native_password",
    **connection_args
):
    """
    Ensure that the named user is present with the specified properties. A
    passwordless user can be configured by omitting ``password`` and
    ``password_hash``, and setting ``allow_passwordless`` to ``True``.

    name
        The name of the user to manage

    host
        Host for which this user/password combo applies

    password
        The password to use for this user. Will take precedence over the
        ``password_hash`` option if both are specified.

    password_hash
        The password in hashed form. Be sure to quote the password because YAML
        doesn't like the ``*``. A password hash can be obtained from the mysql
        command-line client like so::

            mysql> SELECT PASSWORD('mypass');
            +-------------------------------------------+
            | PASSWORD('mypass')                        |
            +-------------------------------------------+
            | *6C8989366EAF75BB670AD8EA7A7FC1176A95CEF4 |
            +-------------------------------------------+
            1 row in set (0.00 sec)

    allow_passwordless
        If ``True``, then ``password`` and ``password_hash`` can be omitted to
        permit a passwordless login.

        .. versionadded:: 0.16.2

    unix_socket
        If ``True`` and allow_passwordless is ``True``, the unix_socket auth
        plugin will be used.
    """
    ret = {
        "name": name,
        "changes": {},
        "result": True,
        "comment": "User {}@{} is already present".format(name, host),
    }

    passwordless = not any((password, password_hash))

    # check if user exists with the same password (or passwordless login)
    if passwordless:
        if not salt.utils.data.is_true(allow_passwordless) and not unix_socket:
            ret["comment"] = (
                "Either password or password_hash must be "
                "specified, unless allow_passwordless is True"
            )
            ret["result"] = False
            return ret
        else:
            if __salt__["mysql.user_exists"](
                name,
                host,
                passwordless=True,
                unix_socket=unix_socket,
                password_column=password_column,
                **connection_args
            ):
                if allow_passwordless:
                    ret["comment"] += " with passwordless login"
                return ret
            else:
                err = _get_mysql_error()
                if err is not None:
                    ret["comment"] = err
                    ret["result"] = False
                    return ret
    else:
        if __salt__["mysql.user_exists"](
            name,
            host,
            password,
            password_hash,
            unix_socket=unix_socket,
            password_column=password_column,
            **connection_args
        ):
            if auth_plugin == "mysql_native_password":
                ret["comment"] += " with the desired password"
                if password_hash and not password:
                    ret["comment"] += " hash"
            else:
                ret["comment"] += ". Unable to verify password."
            return ret
        else:
            err = _get_mysql_error()
            if err is not None:
                ret["comment"] = err
                ret["result"] = False
                return ret

    # check if user exists with a different password
    if __salt__["mysql.user_exists"](
        name, host, unix_socket=unix_socket, **connection_args
    ):

        # The user is present, change the password
        if __opts__["test"]:
            ret["comment"] = "Password for user {}@{} is set to be ".format(name, host)
            ret["result"] = None
            if passwordless:
                ret["comment"] += "cleared"
                if not salt.utils.data.is_true(allow_passwordless):
                    ret["comment"] += ", but allow_passwordless != True"
                    ret["result"] = False
            else:
                ret["comment"] += "changed"
            return ret

        if __salt__["mysql.user_chpass"](
            name,
            host,
            password,
            password_hash,
            allow_passwordless,
            unix_socket,
            **connection_args
        ):
            ret["comment"] = "Password for user {}@{} has been {}".format(
                name, host, "cleared" if passwordless else "changed"
            )
            ret["changes"][name] = "Updated"
        else:
            ret["comment"] = "Failed to {} password for user {}@{}".format(
                "clear" if passwordless else "change", name, host
            )
            err = _get_mysql_error()
            if err is not None:
                ret["comment"] += " ({})".format(err)
            if passwordless and not salt.utils.data.is_true(allow_passwordless):
                ret["comment"] += (
                    ". Note: allow_passwordless must be True "
                    "to permit passwordless login."
                )
            ret["result"] = False
    else:

        err = _get_mysql_error()
        if err is not None:
            ret["comment"] = err
            ret["result"] = False
            return ret

        # The user is not present, make it!
        if __opts__["test"]:
            ret["comment"] = "User {}@{} is set to be added".format(name, host)
            ret["result"] = None
            if allow_passwordless:
                ret["comment"] += " with passwordless login"
                if not salt.utils.data.is_true(allow_passwordless):
                    ret["comment"] += ", but allow_passwordless != True"
                    ret["result"] = False
            if unix_socket:
                ret["comment"] += " using unix_socket"
            return ret

        if __salt__["mysql.user_create"](
            name,
            host,
            password,
            password_hash,
            allow_passwordless,
            unix_socket=unix_socket,
            password_column=password_column,
            auth_plugin=auth_plugin,
            **connection_args
        ):
            ret["comment"] = "The user {}@{} has been added".format(name, host)
            if allow_passwordless:
                ret["comment"] += " with passwordless login"
            if unix_socket:
                ret["comment"] += " using unix_socket"
            ret["changes"][name] = "Present"
        else:
            ret["comment"] = "Failed to create user {}@{}".format(name, host)
            err = _get_mysql_error()
            if err is not None:
                ret["comment"] += " ({})".format(err)
            ret["result"] = False

    return ret


def absent(name, host="localhost", **connection_args):
    """
    Ensure that the named user is absent

    name
        The name of the user to remove
    """
    ret = {"name": name, "changes": {}, "result": True, "comment": ""}

    # Check if user exists, and if so, remove it
    if __salt__["mysql.user_exists"](name, host, **connection_args):
        if __opts__["test"]:
            ret["result"] = None
            ret["comment"] = "User {}@{} is set to be removed".format(name, host)
            return ret
        if __salt__["mysql.user_remove"](name, host, **connection_args):
            ret["comment"] = "User {}@{} has been removed".format(name, host)
            ret["changes"][name] = "Absent"
            return ret
        else:
            err = _get_mysql_error()
            if err is not None:
                ret["comment"] = err
                ret["result"] = False
                return ret
    else:
        err = _get_mysql_error()
        if err is not None:
            ret["comment"] = err
            ret["result"] = False
            return ret

    # fallback
    ret["comment"] = "User {}@{} is not present, so it cannot be removed".format(
        name, host
    )
    return ret
