# Copyright 2011 OpenStack Foundation
# All Rights Reserved.
#
#    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 oslo_log import log as logging
from oslo_utils import importutils
from oslo_utils import strutils
import webob.exc

import trove.common.apischema as apischema
from trove.common import cfg
from trove.common import exception
from trove.common.i18n import _
from trove.common import notification
from trove.common.notification import StartNotification
from trove.common import pagination
from trove.common.utils import correct_id_with_req
from trove.common import wsgi
from trove.extensions.common.service import DefaultRootController
from trove.extensions.mysql.common import populate_users
from trove.extensions.mysql.common import populate_validated_databases
from trove.extensions.mysql.common import unquote_user_host
from trove.extensions.mysql import models
from trove.extensions.mysql import views
from trove.guestagent.db import models as guest_models


LOG = logging.getLogger(__name__)
import_class = importutils.import_class
CONF = cfg.CONF


class UserController(wsgi.Controller):
    """Controller for instance functionality."""
    schemas = apischema.user

    @classmethod
    def get_schema(cls, action, body):
        action_schema = super(UserController, cls).get_schema(action, body)
        if 'update_all' == action:
            update_type = list(body.keys())[0]
            action_schema = action_schema.get(update_type, {})
        return action_schema

    def index(self, req, tenant_id, instance_id):
        """Return all users."""
        LOG.info(_("Listing users for instance '%(id)s'\n"
                   "req : '%(req)s'\n\n") %
                 {"id": instance_id, "req": req})
        context = req.environ[wsgi.CONTEXT_KEY]
        users, next_marker = models.Users.load(context, instance_id)
        view = views.UsersView(users)
        paged = pagination.SimplePaginatedDataView(req.url, 'users', view,
                                                   next_marker)
        return wsgi.Result(paged.data(), 200)

    def create(self, req, body, tenant_id, instance_id):
        """Creates a set of users."""
        LOG.info(_("Creating users for instance '%(id)s'\n"
                   "req : '%(req)s'\n\n"
                   "body: '%(body)s'\n'n") %
                 {"id": instance_id,
                  "req": strutils.mask_password(req),
                  "body": strutils.mask_password(body)})
        context = req.environ[wsgi.CONTEXT_KEY]
        context.notification = notification.DBaaSUserCreate(context,
                                                            request=req)
        users = body['users']
        with StartNotification(context, instance_id=instance_id,
                               username=",".join([user['name']
                                                  for user in users])):
            try:
                model_users = populate_users(users)
                models.User.create(context, instance_id, model_users)
            except (ValueError, AttributeError) as e:
                raise exception.BadRequest(msg=str(e))
        return wsgi.Result(None, 202)

    def delete(self, req, tenant_id, instance_id, id):
        LOG.info(_("Delete instance '%(id)s'\n"
                   "req : '%(req)s'\n\n") %
                 {"id": instance_id, "req": req})
        context = req.environ[wsgi.CONTEXT_KEY]
        id = correct_id_with_req(id, req)
        username, host = unquote_user_host(id)
        context.notification = notification.DBaaSUserDelete(context,
                                                            request=req)
        with StartNotification(context, instance_id=instance_id,
                               username=username):
            user = None
            try:
                user = guest_models.MySQLUser()
                user.name = username
                user.host = host
                found_user = models.User.load(context, instance_id, username,
                                              host)
                if not found_user:
                    user = None
            except (ValueError, AttributeError) as e:
                raise exception.BadRequest(msg=str(e))
            if not user:
                raise exception.UserNotFound(uuid=id)
            models.User.delete(context, instance_id, user.serialize())
        return wsgi.Result(None, 202)

    def show(self, req, tenant_id, instance_id, id):
        """Return a single user."""
        LOG.info(_("Showing a user for instance '%(id)s'\n"
                   "req : '%(req)s'\n\n") %
                 {"id": instance_id, "req": req})
        context = req.environ[wsgi.CONTEXT_KEY]
        id = correct_id_with_req(id, req)
        username, host = unquote_user_host(id)
        user = None
        try:
            user = models.User.load(context, instance_id, username, host)
        except (ValueError, AttributeError) as e:
            raise exception.BadRequest(msg=str(e))
        if not user:
            raise exception.UserNotFound(uuid=id)
        view = views.UserView(user)
        return wsgi.Result(view.data(), 200)

    def update(self, req, body, tenant_id, instance_id, id):
        """Change attributes for one user."""
        LOG.info(_("Updating user attributes for instance '%(id)s'\n"
                   "req : '%(req)s'\n\n") %
                 {"id": instance_id, "req": strutils.mask_password(req)})
        context = req.environ[wsgi.CONTEXT_KEY]
        id = correct_id_with_req(id, req)
        username, hostname = unquote_user_host(id)
        user = None
        user_attrs = body['user']
        context.notification = notification.DBaaSUserUpdateAttributes(
            context, request=req)
        with StartNotification(context, instance_id=instance_id,
                               username=username):
            try:
                user = models.User.load(context, instance_id, username,
                                        hostname)
            except (ValueError, AttributeError) as e:
                raise exception.BadRequest(msg=str(e))
            if not user:
                raise exception.UserNotFound(uuid=id)
            try:
                models.User.update_attributes(context, instance_id, username,
                                              hostname, user_attrs)
            except (ValueError, AttributeError) as e:
                raise exception.BadRequest(msg=str(e))
        return wsgi.Result(None, 202)

    def update_all(self, req, body, tenant_id, instance_id):
        """Change the password of one or more users."""
        LOG.info(_("Updating user password for instance '%(id)s'\n"
                   "req : '%(req)s'\n\n") %
                 {"id": instance_id, "req": strutils.mask_password(req)})
        context = req.environ[wsgi.CONTEXT_KEY]
        context.notification = notification.DBaaSUserChangePassword(
            context, request=req)
        users = body['users']
        with StartNotification(context, instance_id=instance_id,
                               username=",".join([user['name']
                                                  for user in users])):
            model_users = []
            for user in users:
                try:
                    mu = guest_models.MySQLUser()
                    mu.name = user['name']
                    mu.host = user.get('host')
                    mu.password = user['password']
                    found_user = models.User.load(context, instance_id,
                                                  mu.name, mu.host)
                    if not found_user:
                        user_and_host = mu.name
                        if mu.host:
                            user_and_host += '@' + mu.host
                        raise exception.UserNotFound(uuid=user_and_host)
                    model_users.append(mu)
                except (ValueError, AttributeError) as e:
                    raise exception.BadRequest(msg=str(e))
            models.User.change_password(context, instance_id, model_users)
        return wsgi.Result(None, 202)


class UserAccessController(wsgi.Controller):
    """Controller for adding and removing database access for a user."""
    schemas = apischema.user

    @classmethod
    def get_schema(cls, action, body):
        schema = {}
        if 'update_all' == action:
            schema = cls.schemas.get(action).get('databases')
        return schema

    def _get_user(self, context, instance_id, user_id):
        username, hostname = unquote_user_host(user_id)
        try:
            user = models.User.load(context, instance_id, username, hostname)
        except (ValueError, AttributeError) as e:
            raise exception.BadRequest(msg=str(e))
        if not user:
            raise exception.UserNotFound(uuid=user_id)
        return user

    def index(self, req, tenant_id, instance_id, user_id):
        """Show permissions for the given user."""
        LOG.info(_("Showing user access for instance '%(id)s'\n"
                   "req : '%(req)s'\n\n") %
                 {"id": instance_id, "req": req})

        context = req.environ[wsgi.CONTEXT_KEY]
        # Make sure this user exists.
        user_id = correct_id_with_req(user_id, req)
        user = self._get_user(context, instance_id, user_id)
        if not user:
            LOG.error(_("No such user: %(user)s ") % {'user': user})
            raise exception.UserNotFound(uuid=user)
        username, hostname = unquote_user_host(user_id)
        access = models.User.access(context, instance_id, username, hostname)
        view = views.UserAccessView(access.databases)
        return wsgi.Result(view.data(), 200)

    def update(self, req, body, tenant_id, instance_id, user_id):
        """Grant access for a user to one or more databases."""
        LOG.info(_("Granting user access for instance '%(id)s'\n"
                   "req : '%(req)s'\n\n") %
                 {"id": instance_id, "req": req})
        context = req.environ[wsgi.CONTEXT_KEY]
        context.notification = notification.DBaaSUserGrant(
            context, request=req)
        user_id = correct_id_with_req(user_id, req)
        user = self._get_user(context, instance_id, user_id)
        if not user:
            LOG.error(_("No such user: %(user)s ") % {'user': user})
            raise exception.UserNotFound(uuid=user)
        username, hostname = unquote_user_host(user_id)
        databases = [db['name'] for db in body['databases']]
        with StartNotification(context, instance_id=instance_id,
                               username=username, database=databases):
            models.User.grant(context, instance_id, username, hostname,
                              databases)
        return wsgi.Result(None, 202)

    def delete(self, req, tenant_id, instance_id, user_id, id):
        """Revoke access for a user."""
        LOG.info(_("Revoking user access for instance '%(id)s'\n"
                   "req : '%(req)s'\n\n") %
                 {"id": instance_id, "req": req})
        context = req.environ[wsgi.CONTEXT_KEY]
        context.notification = notification.DBaaSUserRevoke(
            context, request=req)
        user_id = correct_id_with_req(user_id, req)
        user = self._get_user(context, instance_id, user_id)
        if not user:
            LOG.error(_("No such user: %(user)s ") % {'user': user})
            raise exception.UserNotFound(uuid=user)
        username, hostname = unquote_user_host(user_id)
        access = models.User.access(context, instance_id, username, hostname)
        databases = [db.name for db in access.databases]
        with StartNotification(context, instance_id=instance_id,
                               username=username, database=databases):
            if id not in databases:
                raise exception.DatabaseNotFound(uuid=id)
            models.User.revoke(context, instance_id, username, hostname, id)
        return wsgi.Result(None, 202)


class SchemaController(wsgi.Controller):
    """Controller for instance functionality."""
    schemas = apischema.dbschema

    def index(self, req, tenant_id, instance_id):
        """Return all schemas."""
        LOG.info(_("Listing schemas for instance '%(id)s'\n"
                   "req : '%(req)s'\n\n") %
                 {"id": instance_id, "req": req})

        context = req.environ[wsgi.CONTEXT_KEY]
        schemas, next_marker = models.Schemas.load(context, instance_id)
        view = views.SchemasView(schemas)
        paged = pagination.SimplePaginatedDataView(req.url, 'databases', view,
                                                   next_marker)
        return wsgi.Result(paged.data(), 200)

    def create(self, req, body, tenant_id, instance_id):
        """Creates a set of schemas."""
        LOG.info(_("Creating schema for instance '%(id)s'\n"
                   "req : '%(req)s'\n\n"
                   "body: '%(body)s'\n'n") %
                 {"id": instance_id,
                  "req": req,
                  "body": body})

        context = req.environ[wsgi.CONTEXT_KEY]
        schemas = body['databases']
        context.notification = notification.DBaaSDatabaseCreate(context,
                                                                request=req)
        with StartNotification(context, instance_id=instance_id,
                               dbname=".".join([db['name']
                                                for db in schemas])):
            model_schemas = populate_validated_databases(schemas)
            models.Schema.create(context, instance_id, model_schemas)
        return wsgi.Result(None, 202)

    def delete(self, req, tenant_id, instance_id, id):
        LOG.info(_("Deleting schema for instance '%(id)s'\n"
                   "req : '%(req)s'\n\n") %
                 {"id": instance_id, "req": req})
        context = req.environ[wsgi.CONTEXT_KEY]
        context.notification = notification.DBaaSDatabaseDelete(
            context, request=req)
        with StartNotification(context, instance_id=instance_id, dbname=id):
            try:
                schema = guest_models.ValidatedMySQLDatabase()
                schema.name = id
                models.Schema.delete(context, instance_id, schema.serialize())
            except (ValueError, AttributeError) as e:
                raise exception.BadRequest(msg=str(e))
        return wsgi.Result(None, 202)

    def show(self, req, tenant_id, instance_id, id):
        raise webob.exc.HTTPNotImplemented()


class MySQLRootController(DefaultRootController):

    def _find_root_user(self, context, instance_id):
        user = guest_models.MySQLRootUser()
        return models.User.load(context, instance_id,
                                user.name, user.host,
                                root_user=True)
