wrapper.js

import Download from './Download';
import DownloadItem from './components/DownloadItem/DownloadItem.js';
import React from "react";

import Enum from './enum.js';

const {DownloadStatus} = Enum;

const events = window.require('events');

Date.prototype.print = function() {
    return `${this.getUTCHours() || 0}h:${this.getUTCMinutes() || 0}m:${this.getUTCSeconds() || 0}s`;
};

export default class DownloadCarrier extends events.EventEmitter {
    constructor(url, name, headers,proxyOptions) {
        super();
        this.url = url;
        this.name = name;
        this.customHeaders = (typeof headers === "string") ? DownloadCarrier.JSONparse(headers) : headers;
        if(this.download){
            this.download.constructor(); // retry download, need to reset everything
        } else {
            this.download = new Download();
        }
        this.headersExpanded = false;

        this.status = DownloadStatus.AWAITING;

        this.done = false;

        this.stats = {};
        this.last_update = 0;

        this.functions = {
            cancel: this.cancel.bind(this),
            remove: this.remove.bind(this),
            retry: this.retry.bind(this),
            toggleHeaders: this.toggleHeaders().bind(this),
        };
/*
        if (window.localStorage.proxySettings === "auth") {
            this.proxyOptions = {
                hostname: window.localStorage.proxyHost,
                port: window.localStorage.proxyPort,
                auth: (window.localStorage.proxyRequiresCredentials === "true") ? {
                    username: window.localStorage.proxyUsername,
                    password: window.localStorage.proxyPassword,
                } : false,
            };
        }
        */
    }


    async initiateDownload() {
        this.emit("init");
        this.download.on('update', info => this.update(info));
        this.download.on('error', err => this.error(err));
        await this.download.init(this.url, this.name, window.localStorage.saveLocation, Number(window.localStorage.partsToCreate), this.customHeaders, this.proxyOptions || false);
    }
    async startDownload() {
        await this.download.beginDownload();
    }

    toggleHeaders() {
        this.headersExpanded = !this.headersExpanded;
    }

    update(info) {
        this.stats = Object.assign({}, this.stats, info);
        if (Date.now() - this.last_update > 800 || info.done) {
            this.last_update = Date.now();
            this.emit("update", this.stats);
        }
    }

    error(err) {
        this.emit("error", err);
    }

    static calculateSize(bytes) {
        let output = bytes;
        let steps = 0;

        let units = [];

        if (window.localStorage.getItem('preferredUnit') === "bin") {
            units = ["B", "KiB", "MiB", "GiB", "TiB", "PiB", "EiB"];

            while (output > 1024) {
                output /= 1024;
                steps++;
            }
        } else if (window.localStorage.getItem('preferredUnit') === "dec") {
            units = ["B", "KB", "MB", "GB", "TB", "PB", "EB"];

            while (output > 1000) {
                output /= 1000;
                steps++;
            }
        }

        return parseFloat(output).toFixed(2) + " " + units[steps];
    }

    async cancel() {
        if (this.download) {
            await this.download.cancel();
        }
        this.emit('cancel');
    }
    remove() {
        this.emit('remove');
    }

    retry(){
        this.emit('retry');
    }

    static JSONparse(str){
        str = str || "{}";
        try {
            JSON.parse(str);
        } catch (e) {
            return false;
        }
        return JSON.parse(str);
    }

    formatProps() {
        return {
            percentage: Number(parseFloat(this.stats.percentage || 0).toFixed(7)),
            progress: `${DownloadCarrier.calculateSize(this.stats.progress || 0)} / ${DownloadCarrier.calculateSize(this.stats.size || 0)}`,
            size: DownloadCarrier.calculateSize(this.stats.size || 0),
            speed: `${DownloadCarrier.calculateSize(this.stats.speed || 0)}/s`,
            eta: `${new Date(this.stats.eta || Date.now()).toLocaleString()} (${new Date(this.stats.eta - Date.now()).print()})` || 0,
            elapsedTime: this.stats.elapsedTime || 0,
            parts: `${this.stats.chunks_done || 0} / ${this.stats.total_chunks || 0}`,
            path: this.stats.path || "",
            url: this.url || "",
            headers: this.customHeaders || "",
            headersExpanded: this.headersExpanded || false,
            error: this.stats.error || "None",
        };
    }


    render(key) {
        return <DownloadItem key={key} status={this.status} functions={this.functions} content={this.formatProps()}/>
    }

}