# Copyright (C) 2018-2019  Lars Wirzenius
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# 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 Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.


import copy
import os
import urllib.parse


import yaml


import ick2


class PersistentStateInterface:  # pragma: no cover

    def get_resource_names(self, token, kind):
        raise NotImplementedError()

    def has_resource(self, token, kind, name):
        raise NotImplementedError()

    def get_resource(self, token, kind, name):
        raise NotImplementedError()

    def get_resources(self, token, kind):
        return [
            self.get_resource(token, kind, name)
            for name in self.get_resource_names(token, kind)
        ]

    def write_resource(self, token, kind, name, resource):
        raise NotImplementedError()

    def update_resource(self, token, kind, name, resource):
        raise NotImplementedError()

    def remove_resource(self, token, kind, name):
        raise NotImplementedError()


class MemoryPersistentState(PersistentStateInterface):

    def __init__(self):
        self._res = {}

    def get_resource_names(self, token, kind):
        if kind not in self._res:
            return []
        return list(self._res[kind].keys())

    def has_resource(self, token, kind, name):
        return kind in self._res and name in self._res[kind]

    def get_resource(self, token, kind, name):
        if kind not in self._res or name not in self._res[kind]:
            raise ick2.NotFound(kind=kind, name=name)
        return self._res[kind][name]

    def write_resource(self, token, kind, name, resource):
        if kind not in self._res:
            self._res[kind] = {}
        self._res[kind][name] = resource

    def update_resource(self, token, kind, name, resource):
        self.write_resource(token, kind, name, resource)

    def remove_resource(self, token, kind, name):
        if kind not in self._res or name not in self._res[kind]:
            raise ick2.NotFound(kind=kind, name=name)
        del self._res[kind][name]


class NotFound(Exception):

    def __init__(self, kind, name):
        super().__init__(
            'Resource {}:{} not found'.format(
                kind or "unknown", name or "unknown"))


class Resource:  # pragma: no cover

    def __init__(self, as_dict=None):
        self._dict = copy.deepcopy(as_dict or {})

    def as_dict(self):
        return copy.deepcopy(self._dict)

    def __getitem__(self, key):
        return self._dict[key]

    def __setitem__(self, key, value):
        self._dict[key] = value

    def __contains__(self, key):
        return key in self._dict

    def __len__(self):
        return len(self._dict)

    def get(self, key, default=None):
        return self._dict.get(key, default)

    def from_dict(self, as_dict):
        self._dict.clear()
        for key in as_dict:
            self[key] = as_dict[key]


def resource_from_dict(as_dict):  # pragma: no cover
    return Resource(as_dict)