# Copyright 2020 Cloudbase Solutions Srl
# All Rights Reserved.

from oslo_log import log as logging
from webob import exc

from coriolis import exception
from coriolis.api.v1.views import service_view
from coriolis.api import wsgi as api_wsgi
from coriolis.policies import services as service_policies
from coriolis.services import api

LOG = logging.getLogger(__name__)


class ServiceController(api_wsgi.Controller):
    def __init__(self):
        self._service_api = api.API()
        super(ServiceController, self).__init__()

    def show(self, req, id):
        context = req.environ["coriolis.context"]
        context.can(service_policies.get_services_policy_label("show"))
        service = self._service_api.get_service(context, id)
        if not service:
            raise exc.HTTPNotFound()

        return service_view.single(req, service)

    def index(self, req):
        context = req.environ["coriolis.context"]
        context.can(service_policies.get_services_policy_label("list"))
        return service_view.collection(
            req, self._service_api.get_services(context))

    def _validate_create_body(self, body):
        try:
            service = body["service"]
            host = service["host"]
            binary = service["binary"]
            topic = service.get("topic")
            mapped_regions = service.get('mapped_regions', [])
            enabled = service.get("enabled", True)
            return host, binary, topic, mapped_regions, enabled
        except Exception as ex:
            LOG.exception(ex)
            if hasattr(ex, "message"):
                msg = ex.message
            else:
                msg = str(ex)
            raise exception.InvalidInput(msg)

    def create(self, req, body):
        context = req.environ["coriolis.context"]
        context.can(service_policies.get_services_policy_label("create"))
        (host, binary, topic, mapped_regions, enabled) = (
            self._validate_create_body(body))
        return service_view.single(req, self._service_api.create(
            context, host=host, binary=binary, topic=topic,
            mapped_regions=mapped_regions, enabled=enabled,
            # NOTE: providers and specs should be auto-discovered later:
            providers={}, specs={}))

    def _validate_update_body(self, body):
        try:
            service = body["service"]
            return {k: service[k] for k in service.keys() & {
                "enabled", "mapped_regions"}}
        except Exception as ex:
            LOG.exception(ex)
            if hasattr(ex, "message"):
                msg = ex.message
            else:
                msg = str(ex)
            raise exception.InvalidInput(msg)

    def update(self, req, id, body):
        context = req.environ["coriolis.context"]
        context.can(service_policies.get_services_policy_label("update"))
        updated_values = self._validate_update_body(body)
        return service_view.single(req, self._service_api.update(
            req.environ['coriolis.context'], id, updated_values))

    def delete(self, req, id):
        context = req.environ["coriolis.context"]
        context.can(service_policies.get_services_policy_label("delete"))
        try:
            self._service_api.delete(req.environ['coriolis.context'], id)
            raise exc.HTTPNoContent()
        except exception.NotFound as ex:
            raise exc.HTTPNotFound(explanation=ex.msg)


def create_resource():
    return api_wsgi.Resource(ServiceController())