#!/usr/bin/python
# -*- coding: utf-8 -*-

# Hive Appier Framework
# Copyright (c) 2008-2024 Hive Solutions Lda.
#
# This file is part of Hive Appier Framework.
#
# Hive Appier Framework is free software: you can redistribute it and/or modify
# it under the terms of the Apache License as published by the Apache
# Foundation, either version 2.0 of the License, or (at your option) any
# later version.
#
# Hive Appier Framework 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
# Apache License for more details.
#
# You should have received a copy of the Apache License along with
# Hive Appier Framework. If not, see <http://www.apache.org/licenses/>.

__author__ = "João Magalhães <joamag@hive.pt>"
""" The author(s) of the module """

__copyright__ = "Copyright (c) 2008-2024 Hive Solutions Lda."
""" The copyright for the module """

__license__ = "Apache License, Version 2.0"
""" The license for the module """

import logging

from . import util
from . import common


class Component(object):
    """
    Top level component class to be used as an abstract definition
    of a loadable/unloadable component of the system.

    This provides a strict (yet simple) set of rules to how such
    component should behave and the life-cycle stages for it.
    """

    def __init__(self, name="component", owner=None, *args, **kwargs):
        object.__init__(self)
        self.id = util.gen_token()
        self.name = name
        self.owner = owner or common.base().APP
        self.loaded = False

    def load(self, *args, **kwargs):
        if self.is_loaded:
            return
        self._load(*args, **kwargs)
        return self

    def unload(self, *args, **kwargs):
        if not self.is_loaded:
            return
        self._unload(*args, **kwargs)
        return self

    def reload(self, *args, **kwargs):
        set_state = kwargs.get("set_state", True)
        owner = self.owner
        state = self.get_state()
        if self.is_loaded:
            self.unload()
        self.owner = owner
        self.load()
        if set_state:
            self.set_state(state)

    def get_state(self):
        return self._get_state()

    def set_state(self, state):
        return self._set_state(state)

    @property
    def logger(self):
        if self.owner:
            return self.owner.logger
        else:
            return logging.getLogger()

    @property
    def is_loaded(self):
        return self.loaded

    def _load(self, *args, **kwargs):
        self.loaded = True

    def _unload(self, *args, **kwargs):
        self.owner = None
        self.loaded = False

    def _get_state(self):
        return dict(owner=self.owner)

    def _set_state(self, state):
        self.owner = state.get("owner", None)