# import zmq
import asyncio
import logging
from .libs.esper import esper
from .libs import zmq
from .libs import umsgpack
import time
import random
import struct
import collections
from enum import Enum

logger = logging.getLogger(__name__)
logging.basicConfig(level=logging.DEBUG)

CONNECT_TIMEOUT = 2 
WAITING_TIME = 0.001

class RCFStatus(Enum):
    IDLE = 1
    CONNECTING = 2
    CONNECTED = 3

class RCFFactory(object):
    """
    Abstract layer used to bridge external and inter
    """
    def init(self, data):
        """
        set the RCFMessage pointer to local data
        """
        print("Default setter")
        #Setup data accessor
        data.get = self.load_getter(data)
        data.set = self.load_setter(data)

        # TODO: Setup local pointer
  

    def load_getter(self, data):
        """
        local program > rcf 

        """
        print("Default getter")
        return None

    def load_setter(self, data):
        """
        rcf > local program
        """
        print("Default setter")
        return None

    def apply(self,data):
        pass

    def diff(self, data):
        """
        Verify data integrity 
        """
        pass

class RCFStore(collections.MutableMapping,dict):
    
    def __init__(self, custom_factory=RCFFactory()):
        super().__init__() 
        self.factory = custom_factory
        
    def __getitem__(self,key):
        return dict.__getitem__(self,key)

    def __setitem__(self, key, value):
        dict.__setitem__(self,key,value)
           
    def __delitem__(self, key):
        dict.__delitem__(self,key)
    def __iter__(self):
        return dict.__iter__(self)
    def __len__(self):
        return dict.__len__(self)
    def __contains__(self, x):
        return dict.__contains__(self,x)

class RCFMessage(object):
    """
    Message is formatted on wire as 2 frames:
    frame 0: key (0MQ string) // property path
    frame 1: id (0MQ string) // property path
    frame 2: mtype (0MQ string) // property path
    frame 3: body (blob) // Could be any data 

    """
    key = None  # key (string)
    id = None  # User  (string)
    mtype = None  # data mtype (string)
    body = None  # data blob

    def __init__(self, key=None, id=None, mtype=None, body=None, pointer=None):
        self.key = key
        self.mtype = mtype
        self.body = body
        self.id = id
        self.pointer = pointer
        self.get = None
        self.set = None
        
    def store(self, dikt):
        """Store me in a dict if I have anything to store"""
        # this currently erasing old value
        if self.key is not None and self.body is not None:
            dikt[self.key] = self
        elif self.key in dikt:
            del dikt[self.key]
        

    def send(self, socket):
        """Send key-value message to socket; any empty frames are sent as such."""
        key = ''.encode() if self.key is None else self.key.encode()
        mtype = ''.encode() if self.mtype is None else self.mtype.encode()
        body = ''.encode() if self.body is None else umsgpack.packb(self.body)
        id = ''.encode() if self.id is None else self.id

        try:
            socket.send_multipart([key, id, mtype, body])
        except:
            logger.info("Fail to send {}".format(key))

    @classmethod
    def recv(cls, socket):
        """Reads key-value message from socket, returns new kvmsg instance."""
        key, id, mtype, body = socket.recv_multipart(zmq.DONTWAIT)
        key = key.decode() if key else None
        id = id if id else None
        mtype = mtype.decode() if body else None
        body = umsgpack.unpackb(body) if body else None

        return cls(key=key, id=id, mtype=mtype, body=body)

    def dump(self):
        if self.body is None:
            size = 0
            data = 'NULL'
        else:
            size = len(self.body)
            data = repr(self.body)
        print("[key:{key}][size:{size}][mtype:{mtype}] {data}".format(
            key=self.key,
            size=size,
            mtype=self.mtype,
            data=data,
        ))

class Client():
    def __init__(
        self, 
        context=zmq.Context(), 
        id="default", 
        on_recv=None, 
        on_post_init=None, 
        is_admin=False, 
        factory=None,
        address="localhost"):

        self.status = RCFStatus.IDLE
        self.is_admin = is_admin

        # 0MQ vars
        self.context = context
        self.pull_sock = None
        self.req_sock = None
        self.poller = None

        self.id = id.encode()
        self.on_recv = on_recv
        self.on_post_init = on_post_init
        
        self.address = address

        self.bind_ports()
        # Main client loop registration
        self.task = asyncio.ensure_future(self.main())

        self.property_map = RCFStore(custom_factory=factory)

        logger.info("{} client initialized".format(id))

    def bind_ports(self):
        # pull socket: get update FROM server
        self.pull_sock = self.context.socket(zmq.SUB)
        self.pull_sock.linger = 0
        self.pull_sock.connect("tcp://{}:5555".format(self.address))
        self.pull_sock.setsockopt_string(zmq.SUBSCRIBE, '')

        # request socket: send request/message over all peers throught the server
        self.req_sock = self.context.socket(zmq.DEALER)
        self.req_sock.setsockopt(zmq.IDENTITY, self.id)
        # self.req_sock.setsockopt(zmq.SNDHWM, 60)
        self.req_sock.linger = 0
        self.req_sock.connect("tcp://{}:5556".format(self.address))

        # push update socket
        self.push_sock = self.context.socket(zmq.PUSH)
        self.push_sock.setsockopt(zmq.IDENTITY, self.id)
        self.push_sock.linger = 0
        self.push_sock.connect("tcp://{}:5557".format(self.address))
        self.push_sock.setsockopt(zmq.SNDHWM, 60)

        # Sockets aggregator, not really used for now
        self.poller = zmq.Poller()
        self.poller.register(self.pull_sock, zmq.POLLIN)

        time.sleep(0.1)

    async def main(self):
        self.status = RCFStatus.CONNECTING
        logger.info("{} client syncing".format(id))

        # Late join mecanism
        logger.info("{} send snapshot request".format(id))
        self.req_sock.send(b"SNAPSHOT_REQUEST")

        while True:
            try:
                rcfmsg_snapshot = RCFMessage.recv(self.req_sock)

                if rcfmsg_snapshot.key == "SNAPSHOT_END":
                    logger.info("snapshot complete")
                    break
                else:
                    logger.info("received : {}".format(rcfmsg_snapshot.key))
                    rcfmsg_snapshot.store(self.property_map)
            except:
                await asyncio.sleep(0.001)

        for f in self.on_post_init:
            f()
        
        logger.info("{} client running".format(id))

        self.push_update("net/clients/{}".format(self.id.decode()),"client",None)
        self.push_update("net/objects/{}".format(self.id.decode()),"client_object",None)
    

        self.status = RCFStatus.CONNECTED
        # Main loop
        while True:
            # TODO: find a better way
            socks = dict(self.poller.poll(1))

            if self.pull_sock in socks:
                rcfmsg = RCFMessage.recv(self.pull_sock)
                
                # if rcfmsg.pointer:
                rcfmsg.store(self.property_map)


                for f in self.on_recv:
                    f(rcfmsg)
            else:
                await asyncio.sleep(0.0001)

    def push_update(self, key, mtype, body):
        rcfmsg = RCFMessage(key, self.id, mtype, body)
        rcfmsg.send(self.push_sock)
        # self.push_sock.send_multipart()

    def stop(self):
        logger.debug("Stopping client")
        self.poller.unregister(self.pull_sock)
        self.req_sock.close()
        self.push_sock.close()
        self.pull_sock.close()
        self.task.cancel()

class Server():
    def __init__(self, context=zmq.Context(), id="admin"):
        self.context = context

        self.pub_sock = None
        self.request_sock = None
        self.collector_sock = None
        self.poller = None

        self.property_map =  RCFStore()
        self.id = id
        self.bind_ports()
        # Main client loop registration
        self.task = asyncio.ensure_future(self.main())

        logger.info("{} client initialized".format(id))

    def bind_ports(self):
        # Update all clients
        self.pub_sock = self.context.socket(zmq.PUB)
        self.pub_sock.setsockopt(zmq.SNDHWM, 60)
        self.pub_sock.bind("tcp://*:5555")
        time.sleep(0.2)

        # Update request
        self.request_sock = self.context.socket(zmq.ROUTER)
        self.request_sock.setsockopt(zmq.IDENTITY, b'SERVER')
        self.request_sock.setsockopt(zmq.RCVHWM, 60)
        self.request_sock.bind("tcp://*:5556")

        # Update collector
        self.collector_sock = self.context.socket(zmq.PULL)
        self.collector_sock.setsockopt(zmq.RCVHWM, 60)
        self.collector_sock.bind("tcp://*:5557")

        # poller for socket aggregation
        self.poller = zmq.Poller()
        self.poller.register(self.request_sock, zmq.POLLIN)
        self.poller.register(self.collector_sock, zmq.POLLIN)

    async def main(self):
        logger.info("{} server launched".format(id))

        while True:
            # Non blocking poller 
            socks = dict(self.poller.poll(1))

            # Snapshot system for late join (Server - Client)
            if self.request_sock in socks:
                msg = self.request_sock.recv_multipart(zmq.DONTWAIT)

                identity = msg[0]
                request = msg[1]

                if request == b"SNAPSHOT_REQUEST":
                    pass
                else:
                    logger.info("Bad snapshot request")
                    break

                for k, v in self.property_map.items():
                    logger.info(
                        "Sending {} snapshot to {}".format(k, identity))
                    self.request_sock.send(identity, zmq.SNDMORE)
                    v.send(self.request_sock)

                msg_end_snapshot = RCFMessage(key="SNAPSHOT_END", id=identity)
                self.request_sock.send(identity, zmq.SNDMORE)
                msg_end_snapshot.send(self.request_sock)
                logger.info("done")

            # Regular update routing (Clients / Client)
            elif self.collector_sock in socks:
                msg = RCFMessage.recv(self.collector_sock)
                # Update all clients
                msg.store(self.property_map)
                msg.send(self.pub_sock)
            else:
                await asyncio.sleep(0.0001)

    def stop(self):
        logger.debug("Stopping server")
        self.poller.unregister(self.request_sock)
        self.pub_sock.close()
        self.request_sock.close()
        self.collector_sock.close()
        self.task.cancel()

        self.status= RCFStatus.IDLE