import urllib
import urllib2
import ssl
import json
from VM import VM
from Node import Node
from Storage import Storage
import time

CACHEFILE='/tmp/zabbix_ticket.json'

def get_auth(host, username, password):
    """
    Handles ticket and csrf token collection for PVEApi class
    :param host: ip of pve host with port
    :param username: zabbix user
    :param password: zabbix password
    :return:  list with csrf token and auth ticket
    """
    postdata = urllib.urlencode({'username': username, 'password': password})
    url = "https://" + host + "/api2/json/access/ticket"
    req = urllib2.Request(url, postdata)
    response = urllib2.urlopen(req, context=ssl._create_unverified_context())
    response = json.load(response)
    return response['data']['CSRFPreventionToken'], response['data']['ticket']


class PVEApi(object):
    """Handle API Connection and authorization"""

    def __init__(self, host, username, password):
        """
        Creates connection object
        :param self:
        :param host: ip of pve host with port
        :param username: zabbix user
        :param password: zabbix password
        :return:
        """
        self.host = host
        self.url = "https://" + self.host + "/api2/json"
        self.username = username
        self.password = password
        if self.check_cacheexpire():
            self.csrftoken = get_auth(self.host, username, password)[0]
            self.ticket = get_auth(self.host, username, password)[1]
            self.write_ticketcache()
        else:
            self.csrftoken = self.read_ticketcache()['csrf']
            self.ticket = self.read_ticketcache()['ticket']

    def check_cacheexpire(self):
        """
        Checks if API ticket is expired.
        Proxmox says ticket is valid for 2 hours. For safety we use 1 hour
        :return: Boolean value of True if ticket is considered expired. False if opposite.
        """
        try:
            with open(CACHEFILE, 'r') as f:
                data = json.load(f)
                timestamp = data['timestamp']
                return True if time.time() - timestamp > 3600 else False
        except:
            self.csrftoken = get_auth(self.host, self.username, self.password)[0]
            self.ticket = get_auth(self.host, self.username, self.password)[1]
            self.write_ticketcache()


    def write_ticketcache(self):
        """
        Function writes API login ticket cache to tmp
        """
        data = {}
        data['csrf'] = self.csrftoken
        data['ticket'] = self.ticket
        data['timestamp'] = time.time()
        with open(CACHEFILE, 'w') as f:
            json.dump(data, f)

    def read_ticketcache(self):
        """
        Reads API login ticket cache file
        :return: returns json parsed dict
        """
        with open(CACHEFILE, 'r') as f:
            data = json.load(f)
            return data


    def get_request(self, url):
        """
        Handles adding auth ticket to API request
        :param url: url to create request to
        :return: request to handle with urlopen
        """
        req = urllib2.Request(url)
        req.add_header('Cookie', 'PVEAuthCookie=' + self.ticket)
        return req

    def get_node_list(self):
        """
        Gets Node names from cluster data
        :return: List of node names
        """
        url = self.url + '/nodes'
        response = json.load(urllib2.urlopen(self.get_request(url), context=ssl._create_unverified_context()))
        resources = response['data']
        nodes = list()
        for node in resources:
            if type(node) is dict:
                nodeobj = Node(node[u'node'].encode("ascii"))
                nodes.append(nodeobj)
        return nodes

    def get_cluster_vmlist(self, nodelist, detailed=False):
        """
        Creates Virtual Machine List
        :return: list of VM class objects
        """
        vmlist = list()
        for node in nodelist:
            url = self.url + '/nodes/' + node.name + '/qemu'
            try:
            	response = json.load(urllib2.urlopen(self.get_request(url), context=ssl._create_unverified_context()))
            except Exception as e:
              	pass
            resources = response['data']
            for machine in resources:
                name = machine[u'name']
                status = machine[u'status']
                uptime = machine[u'uptime']
                diskread = machine[u'diskread']
                diskwrite = machine[u'diskwrite']
                memusage = machine[u'mem']
                pid = machine[u'pid']
                vmid = machine[u'vmid']
                netin = machine[u'netin']
                netout = machine[u'netout']
                cpus = machine[u'cpus']
                template = machine[u'template']
                disk = machine[u'disk']
                cpuusage = machine[u'cpu']
                maxdisk = machine[u'maxdisk']
                maxmem = machine[u'maxmem']
                vm = VM(node, name, status, uptime, diskread, diskwrite, memusage, pid, vmid, netin, netout, cpus,
                        template, disk, cpuusage, maxdisk, maxmem, url)

                if detailed is True:
                    vm_dattr = self.get_details(url, vmid)
                    for k, v in vm_dattr.items():
                        vm.__setattr__('det_' + k, v)

                vmlist.append(vm)
        return vmlist

    def get_details(self, url, vmid):
        """
        Gets vm detailed data from PVE API (its slower than just basic data)
        :param url: url used in vm data get
        :param vmid: vmid to create new url for detailed data
        :return: dict of detailed data params
        """
        url = url + '/' + vmid + '/status/current'
        response = json.load(urllib2.urlopen(self.get_request(url), context=ssl._create_unverified_context()))
        resources = response['data']
        attributedict = dict()
        for param, paramvalue in resources.items():
            attributedict.update({param: paramvalue})
        return attributedict

    def get_cluster_storagelist(self, nodelist):
        """
        Creates Virtual Machine List
        :return: list of VM class objects
        """
        storagelist = list()
        for node in nodelist:
            url = self.url + '/nodes/' + node.name + '/storage'
            response = json.load(urllib2.urlopen(self.get_request(url), context=ssl._create_unverified_context()))
            resources = response['data']
            for storage in resources:
                name = storage[u'storage']
                total = storage[u'total']
                used = storage[u'used']
                active = storage[u'active']
                enabled = storage[u'enabled']
                avail = storage[u'avail']
                try:
                    used_fraction = storage[u'used_fraction']
                except KeyError:
                    used_fraction = "Error getting value"
                stor = Storage(node, name, total, used, active, enabled, avail, used_fraction)
                storagelist.append(stor)
        return storagelist