# Copyright 2014, Rackspace, US, Inc.
#
# 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.
"""API over the nova service.
"""

from django.utils import http as utils_http
from django.views import generic

from openstack_dashboard import api
from openstack_dashboard.api.rest import urls
from openstack_dashboard.api.rest import utils as rest_utils


@urls.register
class Keypairs(generic.View):
    """API for nova keypairs.
    """
    url_regex = r'nova/keypairs/$'

    @rest_utils.ajax()
    def get(self, request):
        """Get a list of keypairs associated with the current logged-in
        account.

        The listing result is an object with property "items".
        """
        result = api.nova.keypair_list(request)
        return {'items': [u.to_dict() for u in result]}

    @rest_utils.ajax(data_required=True)
    def post(self, request):
        """Create a keypair.

        Create a keypair using the parameters supplied in the POST
        application/json object. The parameters are:

        :param name: the name to give the keypair
        :param public_key: (optional) a key to import

        This returns the new keypair object on success.
        """
        if 'public_key' in request.DATA:
            new = api.nova.keypair_import(request, request.DATA['name'],
                                          request.DATA['public_key'])
        else:
            new = api.nova.keypair_create(request, request.DATA['name'])
        return rest_utils.CreatedResponse(
            '/api/nova/keypairs/%s' % utils_http.urlquote(new.name),
            new.to_dict()
        )


@urls.register
class AvailabilityZones(generic.View):
    """API for nova availability zones.
    """
    url_regex = r'nova/availzones/$'

    @rest_utils.ajax()
    def get(self, request):
        """Get a list of availability zones.

        The following get parameters may be passed in the GET
        request:

        :param detailed: If this equals "true" then the result will
            include more detail.

        The listing result is an object with property "items".
        """
        detailed = request.GET.get('detailed') == 'true'
        result = api.nova.availability_zone_list(request, detailed)
        return {'items': [u.to_dict() for u in result]}


@urls.register
class Limits(generic.View):
    """API for nova limits.
    """
    url_regex = r'nova/limits/$'

    @rest_utils.ajax()
    def get(self, request):
        """Get an object describing the current project limits.

        Note: the Horizon API doesn't support any other project (tenant) but
        the underlying client does...

        The following get parameters may be passed in the GET
        request:

        :param reserved: This may be set to "true" but it's not
            clear what the result of that is.

        The result is an object with limits as properties.
        """
        reserved = request.GET.get('reserved') == 'true'
        result = api.nova.tenant_absolute_limits(request, reserved)
        return result


@urls.register
class Servers(generic.View):
    """API over all servers.
    """
    url_regex = r'nova/servers/$'

    _optional_create = [
        'block_device_mapping', 'block_device_mapping_v2', 'nics', 'meta',
        'availability_zone', 'instance_count', 'admin_pass', 'disk_config',
        'config_drive'
    ]

    @rest_utils.ajax(data_required=True)
    def post(self, request):
        """Create a server.

        Create a server using the parameters supplied in the POST
        application/json object. The required parameters as specified by
        the underlying novaclient are:

        :param name: The new server name.
        :param source_id: The ID of the image to use.
        :param flavor_id: The ID of the flavor to use.
        :param key_name: (optional extension) name of previously created
                      keypair to inject into the instance.
        :param user_data: user data to pass to be exposed by the metadata
                      server this can be a file type object as well or a
                      string.
        :param security_groups: An array of one or more objects with a "name"
            attribute.

        Other parameters are accepted as per the underlying novaclient:
        "block_device_mapping", "block_device_mapping_v2", "nics", "meta",
        "availability_zone", "instance_count", "admin_pass", "disk_config",
        "config_drive"

        This returns the new server object on success.
        """
        try:
            args = (
                request,
                request.DATA['name'],
                request.DATA['source_id'],
                request.DATA['flavor_id'],
                request.DATA['key_name'],
                request.DATA['user_data'],
                request.DATA['security_groups'],
            )
        except KeyError as e:
            raise rest_utils.AjaxError(400, 'missing required parameter '
                                       "'%s'" % e.args[0])
        kw = {}
        for name in self._optional_create:
            if name in request.DATA:
                kw[name] = request.DATA[name]

        new = api.nova.server_create(*args, **kw)
        return rest_utils.CreatedResponse(
            '/api/nova/servers/%s' % utils_http.urlquote(new.id),
            new.to_dict()
        )


@urls.register
class Server(generic.View):
    """API for retrieving a single server
    """
    url_regex = r'nova/servers/(?P<server_id>.+|default)$'

    @rest_utils.ajax()
    def get(self, request, server_id):
        """Get a specific server

        http://localhost/api/nova/servers/1
        """
        return api.nova.server_get(request, server_id).to_dict()


@urls.register
class Extensions(generic.View):
    """API for nova extensions.
    """
    url_regex = r'nova/extensions/$'

    @rest_utils.ajax()
    def get(self, request):
        """Get a list of extensions.

        The listing result is an object with property "items". Each item is
        an image.

        Example GET:
        http://localhost/api/nova/extensions
        """
        result = api.nova.list_extensions(request)
        return {'items': [e.to_dict() for e in result]}


@urls.register
class Flavors(generic.View):
    """API for nova flavors.
    """
    url_regex = r'nova/flavors/$'

    @rest_utils.ajax()
    def get(self, request):
        """Get a list of flavors.

        The listing result is an object with property "items". Each item is
        an flavor. By default this will return the flavors for the user's
        current project. If the user is admin, public flavors will also be
        returned.

        :param is_public: For a regular user, set to True to see all public
            flavors. For an admin user, set to False to not see public flavors.
        :param get_extras: Also retrieve the extra specs.

        Example GET:
        http://localhost/api/nova/flavors?is_public=true
        """
        is_public = request.GET.get('is_public')
        is_public = (is_public and is_public.lower() == 'true')
        get_extras = request.GET.get('get_extras')
        get_extras = bool(get_extras and get_extras.lower() == 'true')
        flavors = api.nova.flavor_list(request, is_public=is_public,
                                       get_extras=get_extras)
        result = {'items': []}
        for flavor in flavors:
            d = flavor.to_dict()
            if get_extras:
                d['extras'] = flavor.extras
            result['items'].append(d)
        return result


@urls.register
class Flavor(generic.View):
    """API for retrieving a single flavor
    """
    url_regex = r'nova/flavors/(?P<flavor_id>.+)/$'

    @rest_utils.ajax()
    def get(self, request, flavor_id):
        """Get a specific flavor

        :param get_extras: Also retrieve the extra specs.

        Example GET:
        http://localhost/api/nova/flavors/1
        """
        get_extras = request.GET.get('get_extras')
        get_extras = bool(get_extras and get_extras.lower() == 'true')
        flavor = api.nova.flavor_get(request, flavor_id, get_extras=get_extras)
        result = flavor.to_dict()
        if get_extras:
            result['extras'] = flavor.extras
        return result


@urls.register
class FlavorExtraSpecs(generic.View):
    """API for managing flavor extra specs
    """
    url_regex = r'nova/flavors/(?P<flavor_id>.+)/extra-specs$'

    @rest_utils.ajax()
    def get(self, request, flavor_id):
        """Get a specific flavor's extra specs

        Example GET:
        http://localhost/api/nova/flavors/1/extra-specs
        """
        return api.nova.flavor_get_extras(request, flavor_id, raw=True)