windows-user-space-emulator/page/public/emulator-worker.js

var logLines = [];
var lastFlush = new Date().getTime();

onmessage = async (event) => {
    const data = event.data;
    if (data.message == "run") {
        const payload = data.data;
        runEmulation(payload.filesystem, payload.file, payload.options);
    }
};

function flushLines() {
    const lines = logLines;
    logLines = []; 
    lastFlush = new Date().getTime();
    postMessage({ message: "log", data: lines });
}

function logLine(text) {
    logLines.push(text);

    const now = new Date().getTime();

    if(lastFlush + 15 < now) {
        flushLines();
    }
}

function runEmulation(filesystem, file, options) {
    globalThis.Module = {
        arguments: [...options, "-e", "./root", file],
        onRuntimeInitialized: function () {
            filesystem.forEach(e => {
                if (e.name.endsWith("/")) {
                    FS.mkdir(e.name.slice(0, -1));
                } else {
                    const dirs = e.name.split("/")
                    const file = dirs.pop();
                    const buffer = new Uint8Array(e.data);
                    if (FS.analyzePath(e.name).exists) {
                        FS.unlink(e.name);
                    }
                    FS.createDataFile("/" + dirs.join('/'), file, buffer, true, true);
                }
            })
        },
        print: logLine,
        printErr: logLine,
        postRun: () => {
            flushLines();
            postMessage({ message: "end", data: null });
            self.close();
        },
    };

    importScripts('./analyzer.js?1');
}