"""
Management of PostgreSQL extensions
===================================

A module used to install and manage PostgreSQL extensions.

.. code-block:: yaml

    adminpack:
      postgres_extension.present


.. versionadded:: 2014.7.0
"""

import logging

from salt.modules import postgres

log = logging.getLogger(__name__)


def __virtual__():
    """
    Only load if the postgres module is present
    """
    if "postgres.create_extension" not in __salt__:
        return (
            False,
            "Unable to load postgres module.  Make sure `postgres.bins_dir` is set.",
        )
    return True


def present(
    name,
    if_not_exists=None,
    schema=None,
    ext_version=None,
    from_version=None,
    user=None,
    maintenance_db=None,
    db_user=None,
    db_password=None,
    db_host=None,
    db_port=None,
):
    """
    Ensure that the named extension is present.

    .. note::

        Before you can use the state to load an extension into a database, the
        extension's supporting files must be already installed.

    For more information about all of these options see ``CREATE EXTENSION`` SQL
    command reference in the PostgreSQL documentation.

    name
        The name of the extension to be installed

    if_not_exists
        Add an ``IF NOT EXISTS`` parameter to the DDL statement

    schema
        Schema to install the extension into

    ext_version
        Version to install

    from_version
        Old extension version if already installed

    user
        System user all operations should be performed on behalf of

    maintenance_db
        Database to act on

    db_user
        Database username if different from config or default

    db_password
        User password if any password for a specified user

    db_host
        Database host if different from config or default

    db_port
        Database port if different from config or default
    """
    ret = {
        "name": name,
        "changes": {},
        "result": True,
        "comment": "Extension {} is already present".format(name),
    }
    db_args = {
        "maintenance_db": maintenance_db,
        "runas": user,
        "user": db_user,
        "password": db_password,
        "host": db_host,
        "port": db_port,
    }
    # check if extension exists
    mode = "create"
    mtdata = __salt__["postgres.create_metadata"](
        name, schema=schema, ext_version=ext_version, **db_args
    )

    # The extension is not present, install it!
    toinstall = postgres._EXTENSION_NOT_INSTALLED in mtdata
    if toinstall:
        mode = "install"
    toupgrade = False
    if postgres._EXTENSION_INSTALLED in mtdata:
        for flag in [postgres._EXTENSION_TO_MOVE, postgres._EXTENSION_TO_UPGRADE]:
            if flag in mtdata:
                toupgrade = True
                mode = "upgrade"
    cret = None
    if toinstall or toupgrade:
        if __opts__["test"]:
            ret["result"] = None
            if mode:
                ret["comment"] = "Extension {} is set to be {}ed".format(
                    name, mode
                ).replace("eed", "ed")
            return ret

        cret = __salt__["postgres.create_extension"](
            name=name,
            if_not_exists=if_not_exists,
            schema=schema,
            ext_version=ext_version,
            from_version=from_version,
            **db_args
        )
    if cret:
        if mode.endswith("e"):
            suffix = "d"
        else:
            suffix = "ed"
        ret["comment"] = "The extension {} has been {}{}".format(name, mode, suffix)
        ret["changes"][name] = "{}{}".format(mode.capitalize(), suffix)
    elif cret is not None:
        ret["comment"] = "Failed to {1} extension {0}".format(name, mode)
        ret["result"] = False

    return ret


def absent(
    name,
    if_exists=None,
    restrict=None,
    cascade=None,
    user=None,
    maintenance_db=None,
    db_user=None,
    db_password=None,
    db_host=None,
    db_port=None,
):
    """
    Ensure that the named extension is absent.

    name
        Extension name of the extension to remove

    if_exists
        Add if exist slug

    restrict
        Add restrict slug

    cascade
        Drop on cascade

    user
        System user all operations should be performed on behalf of

    maintenance_db
        Database to act on

    db_user
        Database username if different from config or default

    db_password
        User password if any password for a specified user

    db_host
        Database host if different from config or default

    db_port
        Database port if different from config or default
    """
    ret = {"name": name, "changes": {}, "result": True, "comment": ""}
    db_args = {
        "maintenance_db": maintenance_db,
        "runas": user,
        "host": db_host,
        "user": db_user,
        "port": db_port,
        "password": db_password,
    }
    # check if extension exists and remove it
    exists = __salt__["postgres.is_installed_extension"](name, **db_args)
    if exists:
        if __opts__["test"]:
            ret["result"] = None
            ret["comment"] = "Extension {} is set to be removed".format(name)
            return ret
        if __salt__["postgres.drop_extension"](
            name, if_exists=if_exists, restrict=restrict, cascade=cascade, **db_args
        ):
            ret["comment"] = "Extension {} has been removed".format(name)
            ret["changes"][name] = "Absent"
            return ret
        else:
            ret["result"] = False
            ret["comment"] = "Extension {} failed to be removed".format(name)
            return ret
    else:
        ret["comment"] = "Extension {} is not present, so it cannot be removed".format(
            name
        )

    return ret
