#!/usr/bin/env node

'use strict';

if (process.argv[2] === '--check') {
    console.log('OK');
    process.exit(0);
}

const backuptask = require('../backuptask.js'),
    database = require('../database.js'),
    debug = require('debug')('box:backupupload'),
    safe = require('safetydance'),
    settings = require('../settings.js'),
    v8 = require('v8');

// Main process starts here
const remotePath = process.argv[2];
const format = process.argv[3];
const dataLayoutString = process.argv[4];

debug(`Backing up ${dataLayoutString} to ${remotePath}`);

process.on('SIGTERM', function () {
    process.exit(0);
});

// this can happen when the backup task is terminated (not box code)
process.on('disconnect', function () {
    debug('parent process died');
    process.exit(0);
});

// send progress every n seconds
function throttledProgressCallback(msecs) {
    let lastProgress = null;

    return function (progress) {
        let now = Date.now();
        if (lastProgress && ((now - lastProgress) < msecs)) return;
        process.send(progress);
        lastProgress = now;
    };
}

// https://github.com/josefzamrzla/gc-heap-stats#readme
// https://stackoverflow.com/questions/41541843/nodejs-v8-getheapstatistics-method
function dumpMemoryInfo() {
    const mu = process.memoryUsage();
    const hs = v8.getHeapStatistics();

    function h(bytes) { // human readable
        const i = Math.floor(Math.log(bytes) / Math.log(1024)),
            sizes = ['B', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];

        return (bytes / Math.pow(1024, i)).toFixed(2) * 1 + '' + sizes[i];
    }

    debug(`process: rss=${h(mu.rss)} heapUsed=${h(mu.heapUsed)} heapTotal=${h(mu.heapTotal)} external=${h(mu.external)}`
        + ` v8 heap: used=${h(hs.used_heap_size)} total=${h(hs.total_heap_size)} max=${h(hs.heap_size_limit)}`);
}

(async function main() {
    await database.initialize();
    await settings.initCache();

    dumpMemoryInfo();
    const timerId = setInterval(dumpMemoryInfo, 180 * 1000);

    const [uploadError] = await safe(backuptask.upload(remotePath, format, dataLayoutString, throttledProgressCallback(5000)));
    debug('upload completed. error: ', uploadError);

    process.send({ result: uploadError ? uploadError.message : '' });
    clearInterval(timerId);

    // https://nodejs.org/api/process.html are exit codes used by node. apps.js uses the value below
    // to check apptask crashes
    process.exit(uploadError ? 50 : 0);
})();