"""
Copyright (c) 2017 SONATA-NFV and Paderborn University
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.

Neither the name of the SONATA-NFV, Paderborn University
nor the names of its contributors may be used to endorse or promote
products derived from this software without specific prior written
permission.

This work has been performed in the framework of the SONATA project,
funded by the European Commission under Grant number 671517 through
the Horizon 2020 and 5G-PPP programmes. The authors would like to
acknowledge the contributions of their colleagues of the SONATA
partner consortium (www.sonata-nfv.eu).
"""
from flask import request, Response
from flask_restful import Resource
from emuvim.api.openstack.resources import Stack
from emuvim.api.openstack.openstack_dummies.base_openstack_dummy import BaseOpenstackDummy
from emuvim.api.openstack.helper import get_host
from datetime import datetime
from emuvim.api.openstack.heat_parser import HeatParser
import logging
import json


LOG = logging.getLogger("api.openstack.heat")


class HeatDummyApi(BaseOpenstackDummy):
    def __init__(self, in_ip, in_port, compute):
        super(HeatDummyApi, self).__init__(in_ip, in_port)
        self.compute = compute

        self.api.add_resource(HeatListAPIVersions, "/",
                              resource_class_kwargs={'api': self})
        self.api.add_resource(HeatCreateStack, "/v1/<tenant_id>/stacks",
                              resource_class_kwargs={'api': self})
        self.api.add_resource(HeatShowStack, "/v1/<tenant_id>/stacks/<stack_name_or_id>",
                              "/v1/<tenant_id>/stacks/<stack_name_or_id>/<stack_id>",
                              resource_class_kwargs={'api': self})
        self.api.add_resource(HeatShowStackTemplate, "/v1/<tenant_id>/stacks/<stack_name_or_id>/<stack_id>/template",
                              resource_class_kwargs={'api': self})
        self.api.add_resource(HeatShowStackResources, "/v1/<tenant_id>/stacks/<stack_name_or_id>/<stack_id>/resources",
                              resource_class_kwargs={'api': self})
        self.api.add_resource(HeatUpdateStack, "/v1/<tenant_id>/stacks/<stack_name_or_id>",
                              "/v1/<tenant_id>/stacks/<stack_name_or_id>/<stack_id>",
                              resource_class_kwargs={'api': self})
        self.api.add_resource(HeatDeleteStack, "/v1/<tenant_id>/stacks/<stack_name_or_id>",
                              "/v1/<tenant_id>/stacks/<stack_name_or_id>/<stack_id>",
                              resource_class_kwargs={'api': self})

        @self.app.after_request
        def add_access_control_header(response):
            response.headers['Access-Control-Allow-Origin'] = '*'
            return response


class HeatListAPIVersions(Resource):
    def __init__(self, api):
        self.api = api

    def get(self):
        LOG.debug("API CALL: %s GET" % str(self.__class__.__name__))
        resp = dict()

        resp['versions'] = dict()
        resp['versions'] = [{
            "status": "CURRENT",
            "id": "v1.0",
            "links": [
                {
                    "href": "http://%s:%d/v2.0" % (get_host(request), self.api.port),
                    "rel": "self"
                }
            ]
        }]

        return Response(json.dumps(resp), status=200, mimetype="application/json")


class HeatCreateStack(Resource):
    def __init__(self, api):
        self.api = api

    def post(self, tenant_id):
        """
        Create and deploy a new stack.

        :param tenant_id:
        :return: 409, if the stack name was already used.
            400, if the heat template could not be parsed properly.
            500, if any exception occurred while creation.
            201, if everything worked out.
        """
        LOG.debug("API CALL: %s POST" % str(self.__class__.__name__))

        try:
            stack_dict = json.loads(request.data)
            for stack in self.api.compute.stacks.values():
                if stack.stack_name == stack_dict['stack_name']:
                    return [], 409
            stack = Stack()
            stack.stack_name = stack_dict['stack_name']

            reader = HeatParser(self.api.compute)
            if isinstance(stack_dict['template'], str) or isinstance(stack_dict['template'], unicode):
                stack_dict['template'] = json.loads(stack_dict['template'])
            if not reader.parse_input(stack_dict['template'], stack, self.api.compute.dc.label):
                self.api.compute.clean_broken_stack(stack)
                return 'Could not create stack.', 400

            stack.template = stack_dict['template']
            stack.creation_time = str(datetime.now())
            stack.status = "CREATE_COMPLETE"

            return_dict = {"stack": {"id": stack.id,
                                     "links": [
                                         {
                                             "href": "http://%s:%s/v1/%s/stacks/%s"
                                                     % (get_host(request), self.api.port, tenant_id, stack.id),
                                             "rel": "self"
                                         }]}}

            self.api.compute.add_stack(stack)
            self.api.compute.deploy_stack(stack.id)
            return Response(json.dumps(return_dict), status=201, mimetype="application/json")

        except Exception as ex:
            LOG.exception("Heat: Create Stack exception.")
            return ex.message, 500

    def get(self, tenant_id):
        """
        Calculates information about the requested stack.

        :param tenant_id:
        :return: Returns a json response which contains information like the stack id, name, status, creation time.
            500, if any exception occurred.
            200, if everything worked out.
        """
        LOG.debug("API CALL: %s GET" % str(self.__class__.__name__))
        try:
            return_stacks = dict()
            return_stacks['stacks'] = list()
            for stack in self.api.compute.stacks.values():
                return_stacks['stacks'].append(
                    {"creation_time": stack.creation_time,
                     "description": "desc of " + stack.id,
                     "id": stack.id,
                     "links": [],
                     "stack_name": stack.stack_name,
                     "stack_status": stack.status,
                     "stack_status_reason": "Stack CREATE completed successfully",
                     "updated_time": stack.update_time,
                     "tags": ""
                     })

            return Response(json.dumps(return_stacks), status=200, mimetype="application/json")
        except Exception as ex:
            LOG.exception("Heat: List Stack exception.")
            return ex.message, 500


class HeatShowStack(Resource):
    def __init__(self, api):
        self.api = api

    def get(self, tenant_id, stack_name_or_id, stack_id=None):
        """
        Calculates detailed information about the requested stack.

        :param tenant_id:
        :param stack_name_or_id:
        :param stack_id:
        :return: Returns a json response which contains information like the stack id, name, status, creation time.
            500, if any exception occurred.
            200, if everything worked out.
        """
        LOG.debug("API CALL: %s GET" % str(self.__class__.__name__))
        try:
            stack = None
            if stack_name_or_id in self.api.compute.stacks:
                stack = self.api.compute.stacks[stack_name_or_id]
            else:
                for tmp_stack in self.api.compute.stacks.values():
                    if tmp_stack.stack_name == stack_name_or_id:
                        stack = tmp_stack
            if stack is None:
                return 'Could not resolve Stack - ID', 404

            return_stack = {
                "stack": {
                    "capabilities": [],
                    "creation_time": stack.creation_time,
                    "description": "desc of " + stack.stack_name,
                    "disable_rollback": True,
                    "id": stack.id,
                    "links": [
                        {
                            "href": "http://%s:%s/v1/%s/stacks/%s"
                                    % (get_host(request), self.api.port, tenant_id, stack.id),
                            "rel": "self"
                        }
                    ],
                    "notification_topics": [],
                    "outputs": [],
                    "parameters": {
                        "OS::project_id": "3ab5b02f-a01f-4f95-afa1-e254afc4a435",  # add real project id
                        "OS::stack_id": stack.id,
                        "OS::stack_name": stack.stack_name
                    },
                    "stack_name": stack.stack_name,
                    "stack_owner": "The owner of the stack.",  # add stack owner
                    "stack_status": stack.status,
                    "stack_status_reason": "The reason for the current status of the stack.",  # add status reason
                    "template_description": "The description of the stack template.",
                    "stack_user_project_id": "The project UUID of the stack user.",
                    "timeout_mins": "",
                    "updated_time": "",
                    "parent": "",
                    "tags": ""
                }
            }

            return Response(json.dumps(return_stack), status=200, mimetype="application/json")

        except Exception as ex:
            LOG.exception("Heat: Show stack exception.")
            return ex.message, 500

        
class HeatShowStackTemplate(Resource):
    def __init__(self, api):
        self.api = api

    def get(self, tenant_id, stack_name_or_id, stack_id=None):
        """
        Returns template of given stack.

        :param tenant_id:
        :param stack_name_or_id:
        :param stack_id:
        :return: Returns a json response which contains the stack's template. 
        """
        LOG.debug("API CALL: %s GET" % str(self.__class__.__name__))
        try:
            stack = None
            if stack_name_or_id in self.api.compute.stacks:
                stack = self.api.compute.stacks[stack_name_or_id]
            else:
                for tmp_stack in self.api.compute.stacks.values():
                    if tmp_stack.stack_name == stack_name_or_id:
                        stack = tmp_stack
            if stack is None:
                return 'Could not resolve Stack - ID', 404
            #LOG.debug("STACK: {}".format(stack))
            #LOG.debug("TEMPLATE: {}".format(stack.template))
            return Response(json.dumps(stack.template), status=200, mimetype="application/json")

        except Exception as ex:
            LOG.exception("Heat: Show stack template exception.")
            return ex.message, 500


class HeatShowStackResources(Resource):
    def __init__(self, api):
        self.api = api

    def get(self, tenant_id, stack_name_or_id, stack_id=None):
        """
        Returns template of given stack.

        :param tenant_id:
        :param stack_name_or_id:
        :param stack_id:
        :return: Returns a json response which contains the stack's template. 
        """
        LOG.debug("API CALL: %s GET" % str(self.__class__.__name__))
        try:
            stack = None
            if stack_name_or_id in self.api.compute.stacks:
                stack = self.api.compute.stacks[stack_name_or_id]
            else:
                for tmp_stack in self.api.compute.stacks.values():
                    if tmp_stack.stack_name == stack_name_or_id:
                        stack = tmp_stack
            if stack is None:
                return 'Could not resolve Stack - ID', 404

            response = {"resources": []}

            return Response(json.dumps(response), status=200, mimetype="application/json")

        except Exception as ex:
            LOG.exception("Heat: Show stack template exception.")
            return ex.message, 500


class HeatUpdateStack(Resource):
    def __init__(self, api):
        self.api = api

    def put(self, tenant_id, stack_name_or_id, stack_id=None):
        LOG.debug("API CALL: %s PUT" % str(self.__class__.__name__))
        return self.update_stack(tenant_id, stack_name_or_id, stack_id)

    def patch(self, tenant_id, stack_name_or_id, stack_id=None):
        LOG.debug("API CALL: %s PATCH" % str(self.__class__.__name__))
        return self.update_stack(tenant_id, stack_name_or_id, stack_id)
    
    def update_stack(self, tenant_id, stack_name_or_id, stack_id=None):
        """
        Updates an existing stack with a new heat template.

        :param tenant_id:
        :param stack_name_or_id: Specifies the stack, which should be updated.
        :param stack_id:
        :return: 404, if the requested stack could not be found.
            400, if the stack creation (because of errors in the heat template) or the stack update failed.
            500, if any exception occurred while updating.
            202, if everything worked out.
        """
        try:
            old_stack = None
            if stack_name_or_id in self.api.compute.stacks:
                old_stack = self.api.compute.stacks[stack_name_or_id]
            else:
                for tmp_stack in self.api.compute.stacks.values():
                    if tmp_stack.stack_name == stack_name_or_id:
                        old_stack = tmp_stack
            if old_stack is None:
                return 'Could not resolve Stack - ID', 404

            stack_dict = json.loads(request.data)

            stack = Stack()
            stack.stack_name = old_stack.stack_name
            stack.id = old_stack.id
            stack.creation_time = old_stack.creation_time
            stack.update_time = str(datetime.now())
            stack.status = "UPDATE_COMPLETE"

            reader = HeatParser(self.api.compute)
            if isinstance(stack_dict['template'], str) or isinstance(stack_dict['template'], unicode):
                stack_dict['template'] = json.loads(stack_dict['template'])
            if not reader.parse_input(stack_dict['template'], stack, self.api.compute.dc.label, stack_update=True):
                return 'Could not create stack.', 400
            stack.template = stack_dict['template']

            if not self.api.compute.update_stack(old_stack.id, stack):
                return 'Could not update stack.', 400

            return Response(status=202, mimetype="application/json")

        except Exception as ex:
            LOG.exception("Heat: Update Stack exception")
            return ex.message, 500


class HeatDeleteStack(Resource):
    def __init__(self, api):
        self.api = api

    def delete(self, tenant_id, stack_name_or_id, stack_id=None):
        """
        Deletes an existing stack.

        :param tenant_id:
        :param stack_name_or_id: Specifies the stack, which should be deleted.
        :param stack_id:
        :return: 500, if any exception occurred while deletion.
            204, if everything worked out.
        """
        LOG.debug("API CALL: %s DELETE" % str(self.__class__.__name__))
        try:
            if stack_name_or_id in self.api.compute.stacks:
                self.api.compute.delete_stack(stack_name_or_id)
                return Response("", 204,
                                mimetype='application/json')

            for stack in self.api.compute.stacks.values():
                if stack.stack_name == stack_name_or_id:
                    self.api.compute.delete_stack(stack.id)
                    return Response("", 204,
                                    mimetype='application/json')

        except Exception as ex:
            LOG.exception("Heat: Delete Stack exception")
            return ex.message, 500
