# -*- coding: utf-8 -*-

##
# Copyright 2015 Telefónica Investigación y Desarrollo, S.A.U.
# This file is part of openvim
# 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.
#
# For those usages not covered by the Apache License, Version 2.0 please
# contact with: nfvlabs@tid.es
##

'''
This is thread that interact with the host and the libvirt to manage VM
One thread will be launched per host 
'''
__author__ = "Alfonso Tierno, Pablo Montes"
__date__ = "$10-feb-2017 12:07:15$"

import threading
import time
import Queue
import logging
import vimconn
from db_base import db_base_Exception
from openvim.ovim import ovimException


# from logging import Logger
# import auxiliary_functions as af


def is_task_id(id):
    return True if id[:5] == "TASK." else False


class vim_thread(threading.Thread):

    def __init__(self, vimconn, task_lock, name=None, datacenter_name=None, datacenter_tenant_id=None, db=None, db_lock=None, ovim=None):
        """Init a thread.
        Arguments:
            'id' number of thead
            'name' name of thread
            'host','user':  host ip or name to manage and user
            'db', 'db_lock': database class and lock to use it in exclusion
        """
        self.tasksResult = {}
        """ It will contain a dictionary with
            task_id:
                status: enqueued,done,error,deleted,processing
                result: VIM result,
        """
        threading.Thread.__init__(self)
        self.vim = vimconn
        self.datacenter_name = datacenter_name
        self.datacenter_tenant_id = datacenter_tenant_id
        self.ovim = ovim
        if not name:
            self.name = vimconn["id"] + "." + vimconn["config"]["datacenter_tenant_id"]
        else:
            self.name = name

        self.logger = logging.getLogger('openmano.vim.'+self.name)
        self.db = db
        self.db_lock = db_lock

        self.task_lock = task_lock
        self.task_queue = Queue.Queue(2000)
        self.refresh_list = []
        """Contains time ordered task list for refreshing the status of VIM VMs and nets"""

    def _refres_elements(self):
        """Call VIM to get VMs and networks status until 10 elements"""
        now = time.time()
        vm_to_refresh_list = []
        net_to_refresh_list = []
        vm_to_refresh_dict = {}
        net_to_refresh_dict = {}
        items_to_refresh = 0
        while self.refresh_list:
            task = self.refresh_list[0]
            with self.task_lock:
                if task['status'] == 'deleted':
                    self.refresh_list.pop(0)
                    continue
                if task['time'] > now:
                    break
                task["status"] = "processing"
            self.refresh_list.pop(0)
            if task["name"] == 'get-vm':
                vm_to_refresh_list.append(task["vim_id"])
                vm_to_refresh_dict[task["vim_id"]] = task
            elif task["name"] == 'get-net':
                net_to_refresh_list.append(task["vim_id"])
                net_to_refresh_dict[task["vim_id"]] = task
            else:
                error_text = "unknown task {}".format(task["name"])
                self.logger.error(error_text)
            items_to_refresh += 1
            if items_to_refresh == 10:
                break

        if vm_to_refresh_list:
            try:
                vim_dict = self.vim.refresh_vms_status(vm_to_refresh_list)
                for vim_id, vim_info in vim_dict.items():
                    #look for task
                    task = vm_to_refresh_dict[vim_id]
                    self.logger.debug("get-vm vm_id=%s result=%s", task["vim_id"], str(vim_info))

                    # update database
                    if vim_info.get("error_msg"):
                        vim_info["error_msg"] = self._format_vim_error_msg(vim_info["error_msg"])
                    if task["vim_info"].get("status") != vim_info["status"] or \
                        task["vim_info"].get("error_msg") != vim_info.get("error_msg") or \
                        task["vim_info"].get("vim_info") != vim_info["vim_info"]:
                        with self.db_lock:
                            temp_dict={ "status": vim_info["status"],
                                        "error_msg": vim_info.get("error_msg"),
                                        "vim_info": vim_info["vim_info"]
                                       }
                            self.db.update_rows('instance_vms', UPDATE=temp_dict, WHERE={"vim_vm_id": vim_id})
                    for interface in vim_info["interfaces"]:
                        for task_interface in task["vim_info"]["interfaces"]:
                            if task_interface["vim_net_id"] == interface["vim_net_id"]:
                                break
                        else:
                            task_interface = {"vim_net_id": interface["vim_net_id"]}
                            task["vim_info"]["interfaces"].append(task_interface)
                        if task_interface != interface:
                            #delete old port
                            if task_interface.get("sdn_port_id"):
                                try:
                                    self.ovim.delete_port(task_interface["sdn_port_id"])
                                    task_interface["sdn_port_id"] = None
                                except ovimException as e:
                                    self.logger.error("ovimException deleting external_port={} ".format(
                                        task_interface["sdn_port_id"]) + str(e), exc_info=True)
                                    # TODO Set error_msg at instance_nets
                            vim_net_id = interface.pop("vim_net_id")
                            sdn_net_id = None
                            sdn_port_name = None
                            with self.db_lock:
                                where_= {'iv.vim_vm_id': vim_id, "ine.vim_net_id": vim_net_id,
                                            'ine.datacenter_tenant_id': self.datacenter_tenant_id}
                                # TODO check why vim_interface_id is not present at database
                                # if interface.get("vim_interface_id"):
                                #     where_["vim_interface_id"] = interface["vim_interface_id"]
                                db_ifaces = self.db.get_rows(
                                    FROM="instance_interfaces as ii left join instance_nets as ine on "
                                         "ii.instance_net_id=ine.uuid left join instance_vms as iv on "
                                         "ii.instance_vm_id=iv.uuid",
                                    SELECT=("ii.uuid as iface_id", "ine.uuid as net_id", "iv.uuid as vm_id", "sdn_net_id"),
                                    WHERE=where_)
                            if len(db_ifaces)>1:
                                self.logger.error("Refresing interfaces. "
                                                  "Found more than one interface at database for '{}'".format(where_))
                            elif len(db_ifaces)==0:
                                self.logger.error("Refresing interfaces. "
                                                  "Not found any interface at database for '{}'".format(where_))
                            else:
                                db_iface = db_ifaces[0]
                                if db_iface.get("sdn_net_id") and interface.get("compute_node") and interface.get("pci"):
                                    sdn_net_id = db_iface["sdn_net_id"]
                                    sdn_port_name = sdn_net_id + "." + db_iface["vm_id"]
                                    sdn_port_name = sdn_port_name[:63]
                                    try:
                                        sdn_port_id = self.ovim.new_external_port(
                                            {"compute_node": interface["compute_node"],
                                             "pci": interface["pci"],
                                             "vlan": interface.get("vlan"),
                                             "net_id": sdn_net_id,
                                             "region": self.vim["config"]["datacenter_id"],
                                             "name": sdn_port_name})
                                        interface["sdn_port_id"] = sdn_port_id
                                    except (ovimException, Exception) as e:
                                        self.logger.error(
                                            "ovimException creating new_external_port compute_node={} " \
                                            "pci={} vlan={} ".format(
                                                interface["compute_node"],
                                                interface["pci"],
                                                interface.get("vlan")) + str(e),
                                            exc_info=True)
                                        # TODO Set error_msg at instance_nets
                                with self.db_lock:
                                    self.db.update_rows('instance_interfaces', UPDATE=interface,
                                                    WHERE={'uuid': db_iface["iface_id"]})
                                # TODO insert instance_id
                            interface["vim_net_id"] = vim_net_id

                    task["vim_info"] = vim_info
                    if "ACTIVE" in task["vim_info"]["status"]:
                        self._insert_refresh(task, now+300) # 5minutes
                    else:
                        self._insert_refresh(task, now+5)  # 5seconds
            except vimconn.vimconnException as e:
                self.logger.error("vimconnException Exception when trying to refresh vms " + str(e))
                self._insert_refresh(task, now + 300)  # 5minutes

        if not items_to_refresh:
            time.sleep(1)

    def _insert_refresh(self, task, threshold_time):
        """Insert a task at list of refreshing elements. The refreshing list is ordered by threshold_time (task['time']
        It is assumed that this is called inside this thread
        """
        task["time"] = threshold_time
        for index in range(0, len(self.refresh_list)):
            if self.refresh_list[index]["time"] > threshold_time:
                self.refresh_list.insert(index, task)
                break
        else:
            index = len(self.refresh_list)
            self.refresh_list.append(task)
        self.logger.debug("new refresh task={} name={}, time={} index={}".format(
            task["id"], task["name"], task["time"], index))

    def _remove_refresh(self, task_name, vim_id):
        """Remove a task with this name and vim_id from the list of refreshing elements.
        It is assumed that this is called inside this thread outside _refres_elements method
        Return True if self.refresh_list is modified, task is found
        Return False if not found
        """
        index_to_delete = None
        for index in range(0, len(self.refresh_list)):
            if self.refresh_list[index]["name"] == task_name and self.refresh_list[index]["vim_id"] == vim_id:
                index_to_delete = index
                break
        else:
            return False
        if index_to_delete != None:
            del self.refresh_list[index_to_delete]
        return True

    def insert_task(self, task):
        try:
            self.task_queue.put(task, False)
            return task["id"]
        except Queue.Full:
            raise vimconn.vimconnException(self.name + ": timeout inserting a task")

    def del_task(self, task):
        with self.task_lock:
            if task["status"] == "enqueued":
                task["status"] == "deleted"
                return True
            else:   # task["status"] == "processing"
                self.task_lock.release()
                return False

    def run(self):
        self.logger.debug("Starting")
        while True:
            #TODO reload service
            while True:
                if not self.task_queue.empty():
                    task = self.task_queue.get()
                    self.task_lock.acquire()
                    if task["status"] == "deleted":
                        self.task_lock.release()
                        continue
                    task["status"] = "processing"
                    self.task_lock.release()
                else:
                    self._refres_elements()
                    continue
                self.logger.debug("processing task id={} name={} params={}".format(task["id"], task["name"],
                                                                                   str(task["params"])))
                if task["name"] == 'exit' or task["name"] == 'reload':
                    result, content = self.terminate(task)
                elif task["name"] == 'new-vm':
                    result, content = self.new_vm(task)
                elif task["name"] == 'del-vm':
                    result, content = self.del_vm(task)
                elif task["name"] == 'new-net':
                    result, content = self.new_net(task)
                elif task["name"] == 'del-net':
                    result, content = self.del_net(task)
                else:
                    error_text = "unknown task {}".format(task["name"])
                    self.logger.error(error_text)
                    result = False
                    content = error_text
                self.logger.debug("task id={} name={} result={}:{} params={}".format(task["id"], task["name"],
                                                                                    result, content,
                                                                                    str(task["params"])))

                with self.task_lock:
                    task["status"] = "done" if result else "error"
                    task["result"] = content
                self.task_queue.task_done()

                if task["name"] == 'exit':
                    return 0
                elif task["name"] == 'reload':
                    break

        self.logger.debug("Finishing")

    def terminate(self, task):
        return True, None

    def _format_vim_error_msg(self, error_text):
        if error_text and len(error_text) >= 1024:
            return error_text[:516] + " ... " + error_text[-500:]
        return error_text

    def new_net(self, task):
        try:
            task_id = task["id"]
            params = task["params"]
            net_id = self.vim.new_network(*params)

            net_name = params[0]
            net_type = params[1]

            network = None
            sdn_controller = self.vim.config.get('sdn-controller')
            if sdn_controller and (net_type == "data" or net_type == "ptp"):
                network = {"name": net_name, "type": net_type}

                vim_net = self.vim.get_network(net_id)
                if vim_net.get('encapsulation') != 'vlan':
                    raise vimconn.vimconnException(net_name + "defined as type " + net_type + " but the created network in vim is " + vim_net['encapsulation'])

                network["vlan"] = vim_net.get('segmentation_id')

            sdn_net_id = None
            with self.db_lock:
                if network:
                    sdn_net_id = self.ovim.new_network(network)
                self.db.update_rows("instance_nets", UPDATE={"vim_net_id": net_id, "sdn_net_id": sdn_net_id}, WHERE={"vim_net_id": task_id})

            return True, net_id
        except db_base_Exception as e:
            self.logger.error("Error updating database %s", str(e))
            return True, net_id
        except vimconn.vimconnException as e:
            self.logger.error("Error creating NET, task=%s: %s", str(task_id), str(e))
            try:
                with self.db_lock:
                    self.db.update_rows("instance_nets",
                                        UPDATE={"error_msg": self._format_vim_error_msg(str(e)), "status": "VIM_ERROR"},
                                        WHERE={"vim_net_id": task_id})
            except db_base_Exception as e:
                self.logger.error("Error updating database %s", str(e))
            return False, str(e)
        except ovimException as e:
            self.logger.error("Error creating NET in ovim, task=%s: %s", str(task_id), str(e))
            return False, str(e)

    def new_vm(self, task):
        try:
            params = task["params"]
            task_id = task["id"]
            depends = task.get("depends")
            net_list = params[5]
            error_text = ""
            for net in net_list:
                if "net_id" in net and is_task_id(net["net_id"]):  # change task_id into network_id
                    try:
                        task_net = depends[net["net_id"]]
                        with self.task_lock:
                            if task_net["status"] == "error":
                                error_text = "Cannot create VM because depends on a network that cannot be created: " +\
                                       str(task_net["result"])
                                break
                            elif task_net["status"] == "enqueued" or task_net["status"] == "processing":
                                error_text = "Cannot create VM because depends on a network still not created"
                                break
                            network_id = task_net["result"]
                        net["net_id"] = network_id
                    except Exception as e:
                        error_text = "Error trying to map from task_id={} to task result: {}".format(
                            net["net_id"],str(e))
                        break
            if not error_text:
                vm_id = self.vim.new_vminstance(*params)
            try:
                with self.db_lock:
                    if error_text:
                        update = self.db.update_rows("instance_vms",
                                                     UPDATE={"status": "VIM_ERROR", "error_msg": error_text},
                                                     WHERE={"vim_vm_id": task_id})
                    else:
                        update = self.db.update_rows("instance_vms", UPDATE={"vim_vm_id": vm_id}, WHERE={"vim_vm_id": task_id})
                    if not update:
                        self.logger.error("task id={} name={} database not updated vim_vm_id={}".format(
                            task["id"], task["name"], vm_id))
            except db_base_Exception as e:
                self.logger.error("Error updating database %s", str(e))
            if error_text:
                return False, error_text
            new_refresh_task = {"status": "enqueued",
                                "id": task_id,
                                "name": "get-vm",
                                "vim_id": vm_id,
                                "vim_info": {"interfaces":[]} }
            self._insert_refresh(new_refresh_task, time.time())
            return True, vm_id
        except vimconn.vimconnException as e:
            self.logger.error("Error creating VM, task=%s: %s", str(task_id), str(e))
            try:
                with self.db_lock:
                    self.db.update_rows("instance_vms",
                                        UPDATE={"error_msg": self._format_vim_error_msg(str(e)), "status": "VIM_ERROR"},
                                        WHERE={"vim_vm_id": task_id})
            except db_base_Exception as edb:
                self.logger.error("Error updating database %s", str(edb))
            return False, str(e)

    def del_vm(self, task):
        vm_id = task["params"][0]
        interfaces = task["params"][1]
        if is_task_id(vm_id):
            try:
                task_create = task["depends"][vm_id]
                with self.task_lock:
                    if task_create["status"] == "error":
                        return True, "VM was not created. It has error: " + str(task_create["result"])
                    elif task_create["status"] == "enqueued" or task_create["status"] == "processing":
                        return False, "Cannot delete VM vim_id={} because still creating".format(vm_id)
                    vm_id = task_create["result"]
            except Exception as e:
                return False, "Error trying to get task_id='{}':".format(vm_id, str(e))
        try:
            self._remove_refresh("get-vm", vm_id)
            for iface in interfaces:
                if iface.get("sdn_port_id"):
                    try:
                        self.ovim.delete_port(iface["sdn_port_id"])
                    except ovimException as e:
                        self.logger.error("ovimException deleting external_port={} at VM vim_id={} deletion ".format(
                            iface["sdn_port_id"], vm_id) + str(e), exc_info=True)
                        # TODO Set error_msg at instance_nets

            return True, self.vim.delete_vminstance(vm_id)
        except vimconn.vimconnException as e:
            return False, str(e)

    def del_net(self, task):
        net_id = task["params"][0]
        sdn_net_id = task["params"][1]
        if is_task_id(net_id):
            try:
                task_create = task["depends"][net_id]
                with self.task_lock:
                    if task_create["status"] == "error":
                        return True, "net was not created. It has error: " + str(task_create["result"])
                    elif task_create["status"] == "enqueued" or task_create["status"] == "processing":
                        return False, "Cannot delete net because still creating"
                    net_id = task_create["result"]
            except Exception as e:
                return False, "Error trying to get task_id='{}':".format(net_id, str(e))
        try:
            result = self.vim.delete_network(net_id)
            if sdn_net_id:
                with self.db_lock:
                    self.ovim.delete_network(sdn_net_id)
            return True, result
        except vimconn.vimconnException as e:
            return False, str(e)
        except ovimException as e:
            logging.error("Error deleting network from ovim. net_id: {}, sdn_net_id: {}".format(net_id, sdn_net_id))
            return False, str(e)