# vim: tabstop=4 shiftwidth=4 softtabstop=4

# Copyright (c) 2013 TrilioData, Inc.
# All Rights Reserved.

"""
WSGI middleware for OpenStack API controllers.
"""

import routes

from workloadmgr.api.middleware import fault
from workloadmgr.api import wsgi
from workloadmgr.openstack.common import log as logging
from workloadmgr import utils
from workloadmgr import wsgi as base_wsgi


LOG = logging.getLogger(__name__)

import paste.urlmap

from workloadmgr import flags


FLAGS = flags.FLAGS


def root_app_factory(loader, global_conf, **local_conf):
    if not FLAGS.enable_v1_api:
        del local_conf["/v1"]
    return paste.urlmap.urlmap_factory(loader, global_conf, **local_conf)


class APIMapper(routes.Mapper):
    def routematch(self, url=None, environ=None):
        if url is "":
            result = self._match("", environ)
            return result[0], result[1]
        return routes.Mapper.routematch(self, url, environ)


class ProjectMapper(APIMapper):
    def resource(self, member_name, collection_name, **kwargs):
        if "parent_resource" not in kwargs:
            kwargs["path_prefix"] = "{project_id}/"
        else:
            parent_resource = kwargs["parent_resource"]
            p_collection = parent_resource["collection_name"]
            p_member = parent_resource["member_name"]
            kwargs["path_prefix"] = "{project_id}/%s/:%s_id" % (p_collection, p_member)
        routes.Mapper.resource(self, member_name, collection_name, **kwargs)


class APIRouter(base_wsgi.Router):
    """
    Routes requests on the OpenStack API to the appropriate controller
    and method.
    """

    ExtensionManager = None  # override in subclasses

    @classmethod
    def factory(cls, global_config, **local_config):
        """Simple paste factory, :class:`workloadmgr.wsgi.Router` doesn't have"""
        return cls()

    def __init__(self, ext_mgr=None):
        if ext_mgr is None:
            if self.ExtensionManager:
                ext_mgr = self.ExtensionManager()
            else:
                raise Exception(_("Must specify an ExtensionManager class"))

        mapper = ProjectMapper()
        self.resources = {}
        self._setup_routes(mapper, ext_mgr)
        self._setup_ext_routes(mapper, ext_mgr)
        self._setup_extensions(ext_mgr)
        super(APIRouter, self).__init__(mapper)

    def _setup_ext_routes(self, mapper, ext_mgr):
        for resource in ext_mgr.get_resources():
            LOG.debug(_("Extended resource: %s"), resource.collection)

            wsgi_resource = wsgi.Resource(resource.controller)
            self.resources[resource.collection] = wsgi_resource
            kargs = dict(
                controller=wsgi_resource,
                collection=resource.collection_actions,
                member=resource.member_actions,
            )

            if resource.parent:
                kargs["parent_resource"] = resource.parent

            mapper.resource(resource.collection, resource.collection, **kargs)

            if resource.custom_routes_fn:
                resource.custom_routes_fn(mapper, wsgi_resource)

    def _setup_extensions(self, ext_mgr):
        for extension in ext_mgr.get_controller_extensions():
            ext_name = extension.extension.name
            collection = extension.collection
            controller = extension.controller

            if collection not in self.resources:
                LOG.warning(
                    _(
                        "Extension %(ext_name)s: Cannot extend "
                        "resource %(collection)s: No such resource"
                    )
                    % locals()
                )
                continue

            LOG.debug(
                _("Extension %(ext_name)s extending resource: " "%(collection)s")
                % locals()
            )

            resource = self.resources[collection]
            resource.register_actions(controller)
            resource.register_extensions(controller)

    def _setup_routes(self, mapper, ext_mgr):
        raise NotImplementedError


class FaultWrapper(fault.FaultWrapper):
    def __init__(self, application):
        LOG.warn(
            _(
                "workloadmgr.api.openstack:FaultWrapper is deprecated. Please "
                "use workloadmgr.api.middleware.fault:FaultWrapper instead."
            )
        )
        super(FaultWrapper, self).__init__(application)