# Copyright 2017: Mirantis Inc.
# 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.

import configparser
import os
import re

import requests

from rally.common import logging
from rally import exceptions
from rally.task import utils as task_utils
from rally.verification import context
from rally.verification import utils

from rally_openstack.common import consts
from rally_openstack.common import credential
from rally_openstack.common.services.image import image
from rally_openstack.common.wrappers import network
from rally_openstack.verification.tempest import config as conf


LOG = logging.getLogger(__name__)


@context.configure("tempest", order=900)
class TempestContext(context.VerifierContext):
    """Context class to create/delete resources needed for Tempest."""

    RESOURCE_NAME_FORMAT = "rally_verify_XXXXXXXX_XXXXXXXX"

    def __init__(self, ctx):
        super(TempestContext, self).__init__(ctx)

        openstack_platform = self.verifier.env.data["platforms"]["openstack"]
        admin_creds = credential.OpenStackCredential(
            permission=consts.EndpointPermission.ADMIN,
            **openstack_platform["platform_data"]["admin"])

        self.clients = admin_creds.clients()
        self.available_services = self.clients.services().values()

        self.conf = configparser.ConfigParser(allow_no_value=True)
        self.conf_path = self.verifier.manager.configfile

        self.data_dir = self.verifier.manager.home_dir
        self.image_name = "tempest-image"

        self._created_roles = []
        self._created_images = []
        self._created_flavors = []
        self._created_networks = []

    def setup(self):
        self.conf.read(self.conf_path)

        utils.create_dir(self.data_dir)

        self._create_tempest_roles()

        self._configure_option("DEFAULT", "log_file",
                               os.path.join(self.data_dir, "tempest.log"))
        self._configure_option("oslo_concurrency", "lock_path",
                               os.path.join(self.data_dir, "lock_files"))
        self._configure_option("scenario", "img_dir", self.data_dir)
        self._configure_option("scenario", "img_file", self.image_name,
                               helper_method=self._download_image)
        self._configure_option("compute", "image_ref",
                               helper_method=self._discover_or_create_image)
        self._configure_option("compute", "image_ref_alt",
                               helper_method=self._discover_or_create_image)
        self._configure_option("compute", "flavor_ref",
                               helper_method=self._discover_or_create_flavor,
                               flv_ram=conf.CONF.openstack.flavor_ref_ram,
                               flv_disk=conf.CONF.openstack.flavor_ref_disk)
        self._configure_option("compute", "flavor_ref_alt",
                               helper_method=self._discover_or_create_flavor,
                               flv_ram=conf.CONF.openstack.flavor_ref_alt_ram,
                               flv_disk=conf.CONF.openstack.flavor_ref_alt_disk
                               )
        if "neutron" in self.available_services:
            neutronclient = self.clients.neutron()
            if neutronclient.list_networks(shared=True)["networks"]:
                # If the OpenStack cloud has some shared networks, we will
                # create our own shared network and specify its name in the
                # Tempest config file. Such approach will allow us to avoid
                # failures of Tempest tests with error "Multiple possible
                # networks found". Otherwise the default behavior defined in
                # Tempest will be used and Tempest itself will manage network
                # resources.
                LOG.debug("Shared networks found. "
                          "'fixed_network_name' option should be configured.")
                self._configure_option(
                    "compute", "fixed_network_name",
                    helper_method=self._create_network_resources)
        if "heat" in self.available_services:
            self._configure_option(
                "orchestration", "instance_type",
                helper_method=self._discover_or_create_flavor,
                flv_ram=conf.CONF.openstack.heat_instance_type_ram,
                flv_disk=conf.CONF.openstack.heat_instance_type_disk)

        with open(self.conf_path, "w") as configfile:
            self.conf.write(configfile)

    def cleanup(self):
        # Tempest tests may take more than 1 hour and we should remove all
        # cached clients sessions to avoid tokens expiration when deleting
        # Tempest resources.
        self.clients.clear()

        self._cleanup_tempest_roles()
        self._cleanup_images()
        self._cleanup_flavors()
        if "neutron" in self.available_services:
            self._cleanup_network_resources()

        with open(self.conf_path, "w") as configfile:
            self.conf.write(configfile)

    def _create_tempest_roles(self):
        keystoneclient = self.clients.verified_keystone()
        roles = [conf.CONF.openstack.swift_operator_role,
                 conf.CONF.openstack.swift_reseller_admin_role,
                 conf.CONF.openstack.heat_stack_owner_role,
                 conf.CONF.openstack.heat_stack_user_role]
        existing_roles = set(role.name.lower()
                             for role in keystoneclient.roles.list())

        for role in roles:
            if role.lower() not in existing_roles:
                LOG.debug("Creating role '%s'." % role)
                self._created_roles.append(keystoneclient.roles.create(role))

    def _configure_option(self, section, option, value=None,
                          helper_method=None, *args, **kwargs):
        option_value = self.conf.get(section, option)
        if not option_value:
            LOG.debug("Option '%s' from '%s' section is not configured."
                      % (option, section))
            if helper_method:
                res = helper_method(*args, **kwargs)
                if res:
                    value = res["name"] if "network" in option else res.id
            LOG.debug("Setting value '%s' to option '%s'." % (value, option))
            self.conf.set(section, option, value)
            LOG.debug("Option '{opt}' is configured. "
                      "{opt} = {value}".format(opt=option, value=value))
        else:
            LOG.debug("Option '{opt}' is already configured "
                      "in Tempest config file. {opt} = {opt_val}"
                      .format(opt=option, opt_val=option_value))

    def _discover_image(self):
        LOG.debug("Trying to discover a public image with name matching "
                  "regular expression '%s'. Note that case insensitive "
                  "matching is performed."
                  % conf.CONF.openstack.img_name_regex)
        image_service = image.Image(self.clients)
        images = image_service.list_images(status="active",
                                           visibility="public")
        for image_obj in images:
            if image_obj.name and re.match(conf.CONF.openstack.img_name_regex,
                                           image_obj.name, re.IGNORECASE):
                LOG.debug("The following public image discovered: '%s'."
                          % image_obj.name)
                return image_obj

        LOG.debug("There is no public image with name matching regular "
                  "expression '%s'." % conf.CONF.openstack.img_name_regex)

    def _download_image_from_source(self, target_path, image=None):
        if image:
            LOG.debug("Downloading image '%s' from Glance to %s."
                      % (image.name, target_path))
            with open(target_path, "wb") as image_file:
                for chunk in self.clients.glance().images.data(image.id):
                    image_file.write(chunk)
        else:
            LOG.debug("Downloading image from %s to %s."
                      % (conf.CONF.openstack.img_url, target_path))
            try:
                response = requests.get(conf.CONF.openstack.img_url,
                                        stream=True)
            except requests.ConnectionError as err:
                msg = ("Failed to download image. Possibly there is no "
                       "connection to Internet. Error: %s."
                       % (str(err) or "unknown"))
                raise exceptions.RallyException(msg)

            if response.status_code == 200:
                with open(target_path, "wb") as image_file:
                    for chunk in response.iter_content(chunk_size=1024):
                        if chunk:   # filter out keep-alive new chunks
                            image_file.write(chunk)
                            image_file.flush()
            else:
                if response.status_code == 404:
                    msg = "Failed to download image. Image was not found."
                else:
                    msg = ("Failed to download image. HTTP error code %d."
                           % response.status_code)
                raise exceptions.RallyException(msg)

        LOG.debug("The image has been successfully downloaded!")

    def _download_image(self):
        image_path = os.path.join(self.data_dir, self.image_name)
        if os.path.isfile(image_path):
            LOG.debug("Image is already downloaded to %s." % image_path)
            return

        if conf.CONF.openstack.img_name_regex:
            image = self._discover_image()
            if image:
                return self._download_image_from_source(image_path, image)

        self._download_image_from_source(image_path)

    def _discover_or_create_image(self):
        if conf.CONF.openstack.img_name_regex:
            image_obj = self._discover_image()
            if image_obj:
                LOG.debug("Using image '%s' (ID = %s) for the tests."
                          % (image_obj.name, image_obj.id))
                return image_obj

        params = {
            "image_name": self.generate_random_name(),
            "disk_format": conf.CONF.openstack.img_disk_format,
            "container_format": conf.CONF.openstack.img_container_format,
            "image_location": os.path.join(self.data_dir, self.image_name),
            "visibility": "public"
        }
        LOG.debug("Creating image '%s'." % params["image_name"])
        image_service = image.Image(self.clients)
        image_obj = image_service.create_image(**params)
        LOG.debug("Image '%s' (ID = %s) has been successfully created!"
                  % (image_obj.name, image_obj.id))
        self._created_images.append(image_obj)

        return image_obj

    def _discover_or_create_flavor(self, flv_ram, flv_disk):
        novaclient = self.clients.nova()

        LOG.debug("Trying to discover a flavor with the following properties: "
                  "RAM = %(ram)dMB, VCPUs = 1, disk >= %(disk)dGiB." %
                  {"ram": flv_ram, "disk": flv_disk})
        for flavor in novaclient.flavors.list():
            if (flavor.ram == flv_ram
                    and flavor.vcpus == 1 and flavor.disk >= flv_disk):
                LOG.debug("The following flavor discovered: '{0}'. "
                          "Using flavor '{0}' (ID = {1}) for the tests."
                          .format(flavor.name, flavor.id))
                return flavor

        LOG.debug("There is no flavor with the mentioned properties.")

        params = {
            "name": self.generate_random_name(),
            "ram": flv_ram,
            "vcpus": 1,
            "disk": flv_disk
        }
        LOG.debug("Creating flavor '%s' with the following properties: RAM "
                  "= %dMB, VCPUs = 1, disk = %dGB." %
                  (params["name"], flv_ram, flv_disk))
        flavor = novaclient.flavors.create(**params)
        LOG.debug("Flavor '%s' (ID = %s) has been successfully created!"
                  % (flavor.name, flavor.id))
        self._created_flavors.append(flavor)

        return flavor

    def _create_network_resources(self):
        neutron_wrapper = network.NeutronWrapper(self.clients, self)
        tenant_id = self.clients.keystone.auth_ref.project_id
        router_create_args = {}
        public_net = None
        if self.conf.has_section("network"):
            public_net = self.conf.get("network", "public_network_id")
        if public_net:
            ext_gw_mode_enabled = neutron_wrapper.ext_gw_mode_enabled
            external_gateway_info = {
                "network_id": public_net
            }
            if ext_gw_mode_enabled:
                external_gateway_info["enable_snat"] = True
            router_create_args["external_gateway_info"] = external_gateway_info
        LOG.debug("Creating network resources: network, subnet, router.")
        net = neutron_wrapper.create_network(
            tenant_id, subnets_num=1, add_router=True,
            router_create_args=router_create_args,
            network_create_args={"shared": True})
        LOG.debug("Network resources have been successfully created!")
        self._created_networks.append(net)

        return net

    def _cleanup_tempest_roles(self):
        keystoneclient = self.clients.keystone()
        for role in self._created_roles:
            LOG.debug("Deleting role '%s'." % role.name)
            keystoneclient.roles.delete(role.id)
            LOG.debug("Role '%s' has been deleted." % role.name)

    def _cleanup_images(self):
        image_service = image.Image(self.clients)
        for image_obj in self._created_images:
            LOG.debug("Deleting image '%s'." % image_obj.name)
            self.clients.glance().images.delete(image_obj.id)
            task_utils.wait_for_status(
                image_obj, ["deleted", "pending_delete"],
                check_deletion=True,
                update_resource=image_service.get_image,
                timeout=conf.CONF.openstack.glance_image_delete_timeout,
                check_interval=conf.CONF.openstack.
                glance_image_delete_poll_interval)
            LOG.debug("Image '%s' has been deleted." % image_obj.name)
            self._remove_opt_value_from_config("compute", image_obj.id)

    def _cleanup_flavors(self):
        novaclient = self.clients.nova()
        for flavor in self._created_flavors:
            LOG.debug("Deleting flavor '%s'." % flavor.name)
            novaclient.flavors.delete(flavor.id)
            LOG.debug("Flavor '%s' has been deleted." % flavor.name)
            self._remove_opt_value_from_config("compute", flavor.id)
            self._remove_opt_value_from_config("orchestration", flavor.id)

    def _cleanup_network_resources(self):
        neutron_wrapper = network.NeutronWrapper(self.clients, self)
        for net in self._created_networks:
            LOG.debug("Deleting network resources: router, subnet, network.")
            neutron_wrapper.delete_network(net)
            self._remove_opt_value_from_config("compute", net["name"])
            LOG.debug("Network resources have been deleted.")

    def _remove_opt_value_from_config(self, section, opt_value):
        for option, value in self.conf.items(section):
            if opt_value == value:
                LOG.debug("Removing value '%s' of option '%s' "
                          "from Tempest config file." % (opt_value, option))
                self.conf.set(section, option, "")
                LOG.debug("Value '%s' has been removed." % opt_value)
