#   Copyright 2012-2013 OpenStack Foundation
#
#   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.
#

from keystoneauth1 import exceptions as keystone_exceptions
from keystoneclient.v3.contrib import endpoint_filter
from oslo_utils import importutils

from dcorch.common.endpoint_cache import EndpointCache
from dcorch.common import exceptions
from dcorch.drivers import base

# Ensure keystonemiddleware options are imported
importutils.import_module('keystonemiddleware.auth_token')


class KeystoneClient(base.DriverBase):
    """Keystone V3 driver."""

    def __init__(self, region_name=None, auth_url=None):
        try:
            self.endpoint_cache = EndpointCache(region_name, auth_url)
            self.session = self.endpoint_cache.admin_session
            self.keystone_client = self.endpoint_cache.keystone_client
            self.services_list = self.keystone_client.services.list()
            self.endpoints_list = self.keystone_client.endpoints.list()
        except exceptions.ServiceUnavailable:
            raise

    def get_enabled_projects(self, id_only=True):
        try:
            project_list = self.keystone_client.projects.list()
            if id_only:
                return [current_project.id for current_project in
                        project_list if current_project.enabled]
            else:
                return [current_project for current_project in
                        project_list if current_project.enabled]
        except exceptions.InternalError:
            raise

    def get_project_by_id(self, projectid):
        if not projectid:
            return None
        try:
            return self.keystone_client.projects.get(projectid)
        except exceptions.InternalError:
            raise

    def get_project_by_name(self, projectname):
        if not projectname:
            return None
        try:
            project_list = self.get_enabled_projects(id_only=False)
            for project in project_list:
                if project.name == projectname:
                    return project
        except Exception:
            raise

    def get_enabled_users(self, id_only=True):
        try:
            user_list = self.keystone_client.users.list()
            if id_only:
                return [current_user.id for current_user in
                        user_list if current_user.enabled]
            else:
                return [current_user for current_user in
                        user_list if current_user.enabled]
        except exceptions.InternalError:
            raise

    def get_user_by_id(self, userid):
        if not userid:
            return None
        try:
            return self.keystone_client.users.get(userid)
        except exceptions.InternalError:
            raise

    def get_user_by_name(self, username):
        if not username:
            return None
        try:
            user_list = self.get_enabled_users(id_only=False)
            for user in user_list:
                if user.name == username:
                    return user
        except Exception:
            raise

    def is_service_enabled(self, service):
        try:
            for current_service in self.services_list:
                if service in current_service.type:
                    return True
            return False
        except exceptions.InternalError:
            raise

    # Returns list of regions if endpoint filter is applied for the project
    def get_filtered_region(self, project_id):
        try:
            region_list = []
            endpoint_manager = endpoint_filter.EndpointFilterManager(
                self.keystone_client)
            endpoint_lists = endpoint_manager.list_endpoints_for_project(
                project_id)
            for endpoint in endpoint_lists:
                region_list.append(endpoint.region)
            return region_list
        except exceptions.InternalError:
            raise
        except keystone_exceptions.NotFound:
            raise exceptions.ProjectNotFound(project_id=project_id)

    def delete_endpoints(self, region_name):
        endpoints = self.keystone_client.endpoints.list(region=region_name)
        for endpoint in endpoints:
            self.keystone_client.endpoints.delete(endpoint)

    def delete_region(self, region_name):
        try:
            self.keystone_client.regions.delete(region_name)
        except keystone_exceptions.NotFound:
            pass