script.js

const gdriveUriInputEl = document.getElementById("gdrive-uri");
const fileFnInputEl = document.getElementById("file-fn");
const fileLargeInputEl = document.getElementById("file-large");
const copyButtonEl = document.getElementById("copy");
const wgetCmdCodeEl = document.getElementById("wget-cmd");

let wgetCmd = "";

function copyToClipboard() {
    const text = wgetCmd;
    const dummy = document.createElement("textarea");
    document.body.appendChild(dummy);
    dummy.value = text;
    dummy.select();
    document.execCommand("copy");
    document.body.removeChild(dummy);
}

function onChange() {
    const gdriveUri = gdriveUriInputEl.value;
    if (gdriveUri.length === 0) {
        return;
    }

    const gdriveIdSplit = gdriveUri.split("=");
    const gdriveId = gdriveIdSplit[gdriveIdSplit.length - 1];
    const fileFn = fileFnInputEl.value;

    if (fileLargeInputEl.checked) {
        wgetCmd = `wget --load-cookies /tmp/cookies.txt "https://docs.google.com/uc?export=download&confirm=$(wget --quiet --save-cookies /tmp/cookies.txt --keep-session-cookies --no-check-certificate 'https://docs.google.com/uc?export=download&id=${gdriveId}' -O- | sed -rn 's/.*confirm=([0-9A-Za-z_]+).*/\\1\\n/p')&id=${gdriveId}" -O ${fileFn} && rm -rf /tmp/cookies.txt`;
    } else {
        wgetCmd = `wget --no-check-certificate 'https://docs.google.com/uc?export=download&id=${gdriveId}' -O ${fileFn}`;
    }

    wgetCmdCodeEl.innerHTML = wgetCmd;
    wgetCmdCodeEl.style.display = "block";
    copyButtonEl.style.display = "block";
}

gdriveUriInputEl.oninput = onChange;
fileFnInputEl.oninput = onChange;
fileLargeInputEl.onclick = onChange;
copyButtonEl.onclick = copyToClipboard;