/*
 * Copyright (C) 2020-2022 CZ.NIC z.s.p.o. (http://www.nic.cz/)
 *
 * This is free software, licensed under the GNU General Public License v3.
 * See /LICENSE for more information.
 */

/* eslint no-console: "off" */

import { REFORIS_URL_PREFIX } from "../utils/forisUrls";

const { io } = require("socket.io-client");

export class WebSockets {
    constructor() {
        this.socket = io("/notifications", {
            path: `${REFORIS_URL_PREFIX}/reforis-ws`,
        });
        this.connection = null;
        this.socket.on("disconnect", (reason) => {
            this.connection = null;
            console.debug(`SocketIO disconnected (${reason})`);
        });
        this.socket.on("notification", (message) => {
            console.debug("WS: Received Message:", message);
            this.dispatch(message);
        });
        this.socket.on("connect", (connection) => {
            this.connection = connection;
            console.debug(`SocketIO connected.`);
        });

        // callbacks[module][action]
        this.callbacks = {};
    }

    bind(module, action, callback) {
        this.callbacks[module] = this.callbacks[module] || {};
        this.callbacks[module][action] = this.callbacks[module][action] || [];
        this.callbacks[module][action].push(callback);
        return this;
    }

    unbind(module, action, callback) {
        const callbacks = this.callbacks[module][action];

        const index = callbacks.indexOf(callback);
        if (index !== -1) {
            callbacks.splice(index, 1);
        }

        if (callbacks.length === 0) {
            delete this.callbacks[module][action];
        }

        if (Object.keys(this.callbacks[module]).length === 0) {
            delete this.callbacks[module];
        }

        return this;
    }

    dispatch(json) {
        if (!json.module) return;

        let chain;
        try {
            chain = this.callbacks[json.module][json.action];
        } catch (error) {
            if (error instanceof TypeError) {
                console.debug(
                    `Callbacks for this module wasn't found: ${json.module}`
                );
            } else throw error;
        }

        if (typeof chain === "undefined") return;

        console.debug("Handling WS message", json);
        chain.forEach((callback) => callback(json));
    }
}