/**
 * @author Martin Karkowski
 * @email m.karkowski@zema.de
 * @create date 2020-11-06 08:52:42
 * @modify date 2020-11-06 08:52:43
 * @desc [description]
 */

import { Server } from "http";
import * as io from 'socket.io';
import { getNopeLogger } from "../logger/getLogger";
import { Logger } from "winston";
import { IAvailableInstanceGeneratorsMsg, IAvailableServicesMsg, IAvailableTopicsMsg, ICommunicationInterface, IExternalEventMsg, IRequestTaskMsg, IResponseTaskMsg, ITaskCancelationMsg } from "../types/nope/nopeCommunication.interface";

/**
 * Wrapper Interface. 
 * Creates an Interface for a Socket server 
 */
export class IoSocketSeverEventEmitter {
  protected _socket: io.Server
  protected _sockets: Set<io.Socket>;
  protected _funcs: Map<string, (...args: any[]) => void>;
  protected _logger: Logger;

  /**
   * Creates an instance of IoSocketServer.
   * @param {number} port The Port, on which the Server should be hosted
   * @param {Server} [server] A Server shich should be used. (Otherwise a Server is created)
   * @memberof IoSocketServer
   */
  constructor(public port: number, server?: Server) {
    if (server) {
      this._socket = (io as any)(server);
    } else {
      this._socket = (io as any)();
    }

    this._logger = getNopeLogger('io-socket');

    this._socket.listen(port);

    const _this = this;
    this._socket.on('connection', (client) => {

      _this._logger.debug('New Connection established: ' + client.id);

      // Add the Elements to the Client
      _this._sockets.add(client);

      // Subscribe to Loosing connection:
      client.on('disconnect', () => {
        _this._logger.debug('Connection of : ' + client.id + ' lost.');
        _this._sockets.delete(client);
      });

      for (const [id, _func] of _this._funcs) {
        // Subscribe to the Events:
        client.on(id, (...args) => {
          _this._logger.debug('received content: ', ...args);

          // Forward the Message.
          _func(...args);
        });
      }
    });

    this._sockets = new Set();
    this._funcs = new Map<string, (...args: any[]) => void>();
  }
  off(event: string, cb: (...args: any[]) => void) {
    // Remove the Subscription from the Socket.
    for (const socket of this._sockets) {
      socket.off(event, cb);
    }

    // Remove the Function.
    this._funcs.delete(event);
  }

  on(event: string, cb: (...args: any[]) => void) {
    // Add the Subscription to the Sockets.
    for (const socket of this._sockets) {
      socket.on(event, cb);
    }

    // Store the Function
    this._funcs.set(event, cb);
  }

  emit(event: string, data: any): void {
    if (this._logger.isDebugEnabled()) {
      this._logger.debug('sending data on: ' + event);
    }
    this._socket.emit(event, data);
  }
}


/**
 * Communication Layer using IO-Sockets.
 *
 * @export
 * @class IoSocketServer
 * @implements {ICommunicationInterface}
 */
export class IoSocketServer implements ICommunicationInterface {

  protected _emitter: IoSocketSeverEventEmitter

  constructor(
    public port: number,
    public readonly subscriptionMode: 'individual' | 'generic',
    public readonly resultSharing: 'individual' | 'generic',
    server?: Server,
    protected _logger?: Logger
  ) {
    this._emitter = new IoSocketSeverEventEmitter(port, server);
  }

  async onTaskCancelation(cb: (msg: ITaskCancelationMsg) => void) {
    this._emitter.on('cancel',cb);
  }

  async emitTaskCancelation(msg: ITaskCancelationMsg) {
    this._emitter.emit('cancel', msg);
  }

  async onAurevoir(cb: (dispatcher: string) => void) {
    this._emitter.on('aurevoir', cb);
  }

  async emitAurevoir(dispatcher: string) {
    this._emitter.emit('aurevoir', dispatcher);
  }

  async emitNewInstanceGeneratorsAvailable(generators: IAvailableInstanceGeneratorsMsg) {
    this._emitter.emit('generators',generators);
  }

  async onNewInstanceGeneratorsAvailable(cb: (generators: IAvailableInstanceGeneratorsMsg) => void) {
    this._emitter.on('generators',cb)
  }

  async emitRpcRequest(name: string, request: IRequestTaskMsg){
    this._emitter.emit(name, request);
  }

  async emitRpcResult(name: string, result: IResponseTaskMsg){
    this._emitter.emit(name,result);
  }

  async onRpcResult(name: string, cb: (result: IResponseTaskMsg) => void){
    this._emitter.on(name, cb);
  }

  async offRpcResponse(name: string, cb: (result: IResponseTaskMsg) => void){
    this._emitter.off(name, cb);
  }

  async onRpcRequest(name: string, cb: (data: IRequestTaskMsg) => void){
    this._emitter.on(name, cb);
  }

  async offRpcRequest(name: string, cb: (data: IRequestTaskMsg) => void){
    this._emitter.off(name, cb);
  }

  async emitNewServicesAvailable(services: IAvailableServicesMsg){
    this._emitter.emit('services', services)
  }

  async onNewServicesAvailable(cb: (services: IAvailableServicesMsg) => void) {
    this._emitter.on('services', cb);
  }

  async onBonjour(cb: (dispatcher: string) => void){
    this._emitter.on('bonjour', cb);
  }

  async emitBonjour(dispatcher: string){
    this._emitter.emit('bonjour', dispatcher);
  }

  async emitNewTopicsAvailable(topics: IAvailableTopicsMsg){
    this._emitter.emit('topics',topics)
  }

  async onNewTopicsAvailable(cb: (topics: IAvailableTopicsMsg) => void) {
    this._emitter.on('topics',cb)
  }

  async onEvent(event: string, cb: (data: IExternalEventMsg) => void){
    this._emitter.on('event_'+event, cb);
  }

  async emitEvent(event: string, data: IExternalEventMsg){
    this._emitter.emit('event_'+event, data)
  }
  
  async offEvent(event: string, cb: (data: IExternalEventMsg) => void){
    this._emitter.off('event_'+event, cb);
  }
}