/*
* Tencent is pleased to support the open source community by making Puerts available.
* Copyright (C) 2020 THL A29 Limited, a Tencent company.  All rights reserved.
* Puerts is licensed under the BSD 3-Clause License, except for the third-party components listed in the file 'LICENSE' which may be subject to their corresponding license terms.
* This file is subject to the terms and conditions defined in file 'LICENSE', which is part of this source code package.
*/

var global = global || (function () { return this; }());
(function (global) {
    const WebSocketPP = global.WebSocketPP;
    //global.WebSocketPP = undefined;
    
    class EventTarget {
      constructor() {
        this.listeners = {};
      }

      addEventListener(type, callback) {
        if (!(type in this.listeners)) {
          this.listeners[type] = [];
        }
        this.listeners[type].push(callback);
      }

      removeEventListener(type, callback) {
        if (!(type in this.listeners)) {
          return;
        }
        const stack = this.listeners[type];
        for (let i = 0; i < stack.length; i++) {
          if (stack[i] === callback) {
            stack.splice(i, 1);
            return;
          }
        }
      }

      dispatchEvent(ev) {
        if (!(ev.type in this.listeners)) {
          return true;
        }
        const stack = this.listeners[ev.type].slice();

        for (let i = 0; i < stack.length; i++) {
          stack[i].call(this, ev);
        }
        return !ev.defaultPrevented;
      }
    }
    
    const readyStates = ['CONNECTING', 'OPEN', 'CLOSING', 'CLOSED'];
    
    const poll_ws_objects = [];
    
    class WebSocket extends EventTarget {
        constructor(url, protocols) {
            super();
            if (protocols) throw new Error('do not support protocols argument');
            this._raw = new WebSocketPP(url);
            this._url = url;
            // !!do not raise exception in handles.
            this._raw.setHandles(
            ()=> {
                this._readyState = WebSocket.OPEN;
                this._addPendingEvent({type:'open'});
            }, 
            (data) => {
                this._addPendingEvent({type:'message', data:data, origin:this._url});
            }, 
            (code, reason) => {
                this._cleanup();
                this._addPendingEvent({type:'close', code:code, reason: reason});
            }, 
            () => {
                this._addPendingEvent({type:'error'});
                this._cleanup();
                this._addPendingEvent({type:'close', code:1006, reason: ""});
            });
            
            this._readyState = WebSocket.CONNECTING;
            this._tid = setInterval(() => this._poll(), 1);
            this._pendingEvents = [];
        }
        
        get url() {
            return this._url;
        }
        
        get readyState() {
            return this._readyState;
        }
        
        send(data) {
            if (this._readyState !== WebSocket.OPEN) {
              throw new Error(`WebSocket is not open: readyState ${this._readyState} (${readyStates[this._readyState]})`);
            }
            this._raw.send(data);
        }
        
        _cleanup() {
            this._readyState = WebSocket.CLOSING;
        }
        
        _addPendingEvent(ev) {
            this._pendingEvents.push(ev);
        }
        
        _poll() {
            if (this._pendingEvents.length === 0 && this._readyState != WebSocket.CLOSING) {
                this._raw.poll();
            } 
            const ev = this._pendingEvents.shift();
            if (ev) this.dispatchEvent(ev);
            if (this._pendingEvents.length === 0 && this._readyState == WebSocket.CLOSING) {
                this._raw = undefined;
                clearInterval(this._tid);
                this._readyState = WebSocket.CLOSED;
            }
        }
        
        close(code, data) {
            try {
                this._raw.close(code, data);
            } catch(e) {}
            this._cleanup();
        }
        
    }
    
    for (let i = 0; i < readyStates.length; i++) {
        Object.defineProperty(WebSocket, readyStates[i], {
            enumerable: true,
            value: i
        });
        
        Object.defineProperty(WebSocket.prototype, readyStates[i], {
            enumerable: true,
            value: i
        });
    }
    
    global.WebSocket = WebSocket;

}(global));