cables_dev/cables/src/core/eventtarget.js

import { Logger } from "cables-shared-client";
 
const EventTarget = function ()
{
    this._log = new Logger("eventtarget");
    this._eventCallbacks = {};
    this._logName = "";
    this._logEvents = false;
    this._listeners = {};
 
    this.addEventListener = this.on = function (which, cb, idPrefix)
    {
        const event =
        {
            "id": (idPrefix || "") + CABLES.simpleId(),
            "name": which,
            "cb": cb,
        };
        if (!this._eventCallbacks[which]) this._eventCallbacks[which] = [event];
        else this._eventCallbacks[which].push(event);
 
        this._listeners[event.id] = event;
 
        return event.id;
    };
 
    this.hasEventListener = function (which, cb)
    {
        if (which && !cb)
        {
            // check by id
            if (this._listeners[which]) return true;
            else return false;
        }
        else
        {
            this._log.warn("old eventtarget function haseventlistener!");
            if (which && cb)
            {
                if (this._eventCallbacks[which])
                {
                    const idx = this._eventCallbacks[which].indexOf(cb);
                    if (idx == -1) return false;
                    return true;
                }
            }
        }
    };
 
    this.hasListenerForEventName = function (eventName)
    {
        return this._eventCallbacks[eventName] && this._eventCallbacks[eventName].length > 0;
    };
 
    this.removeEventListener = this.off = function (which, cb)
    {
        if (which === null || which === undefined) return;
 
        if (!cb) // new style, remove by id, not by name/callback
        {
            const event = this._listeners[which];
            if (!event)
            {
                this._log.log("removeEvent: could not find event...", which, this);
                return;
            }
 
            let found = true;
            while (found)
            {
                found = false;
                let index = -1;
                for (let i = 0; i < this._eventCallbacks[event.name].length; i++)
                {
                    if (this._eventCallbacks[event.name][i].id.startsWith(which)) // this._eventCallbacks[event.name][i].id == which ||
                    {
                        found = true;
                        index = i;
                    }
                }
 
                if (index !== -1)
                {
                    this._eventCallbacks[event.name].splice(index, 1);
                    delete this._listeners[which];
                }
            }
 
            return;
        }
 
        this._log.info("[eventtaget] ", "old function signature: removeEventListener! use listener id");
        this._log.log((new Error()).stack);
 
        let index = null;
        for (let i = 0; i < this._eventCallbacks[which].length; i++)
            if (this._eventCallbacks[which][i].cb == cb)
                index = i;
 
        if (index !== null)
        {
            delete this._eventCallbacks[index];
        }
        else this._log.warn("removeEventListener not found " + which);
    };
 
    this.logEvents = function (enabled, name)
    {
        this._logEvents = enabled;
        this._logName = name;
    };
 
    this.emitEvent = function (which, param1, param2, param3, param4, param5, param6)
    {
        if (this._logEvents) this._log.log("[event] ", this._logName, which, this._eventCallbacks);
 
        if (this._eventCallbacks[which])
        {
            for (let i = 0; i < this._eventCallbacks[which].length; i++)
            {
                if (this._eventCallbacks[which][i])
                {
                    this._eventCallbacks[which][i].cb(param1, param2, param3, param4, param5, param6);
                }
            }
        }
        else
        {
            if (this._logEvents) this._log.log("[event] has no event callback", which, this._eventCallbacks);
        }
    };
};
 
export { EventTarget };