UserScript: Copy Selected Links

userscript.js

// ==UserScript==
// @name Copy Selected Links
// @description Copies selected links on pressing a hotkey (default: Alt+C / Option+C)
// @version 1
// @match *://*/*
// ==/UserScript==

// Configuration
const preferUI = false;
const hotkey = e => e.altKey && ["c", "C"].includes(e.key);

async function copy(content) {
    if (!preferUI && navigator.clipboard) {
        try {
            await navigator.clipboard.writeText(content);
            return;
        } catch (e) {
            console.warn("Could not copy links to clipboard.", e);
        }
    }

    // Fallback for when clipboard is not available (unsafe site)

    let textArea = document.createElement("textarea");
    textArea.style.setProperty("position", "fixed", "important");
    textArea.style.setProperty("z-index", "9999", "important");
    textArea.style.setProperty("inset", "0", "important");
    textArea.style.setProperty("margin", "0", "important");
    textArea.style.setProperty("padding", "1em", "important");
    textArea.style.setProperty("border", "none", "important");
    textArea.style.setProperty("box-sizing", "border-box", "important");
    textArea.style.setProperty("width", "100vw", "important");
    textArea.style.setProperty("height", "100vh", "important");
    textArea.style.setProperty("font-family", "monospace", "important");
    textArea.style.setProperty("font-size", "11pt", "important");
    textArea.style.setProperty("color", "#ccc", "important");
    textArea.style.setProperty("background-color", "#333", "important");

    let previousSelectionRanges = [];
    let selection = window.getSelection();
    for (let i = 0; i < selection.rangeCount; i++) {
        previousSelectionRanges.push(selection.getRangeAt(i));
    }

    function close(e) {
        if (e && e.clipboardData) {
            try {
                // Set manually (textArea might be removed before content was copied)
                let data = textArea.value.substring(textArea.selectionStart, textArea.selectionEnd);
                e.clipboardData.setData("text/plain", data);
                e.preventDefault();
            } catch (e) {
                // Potential security limitations
                console.warn(e);
            }
        }

        // Delay for possible fallback / catch behavior
        window.requestAnimationFrame(() => {
            textArea.remove();
            selection.removeAllRanges();
            for (let r of previousSelectionRanges) {
                selection.addRange(r);
            }
        });
    }

    textArea.addEventListener("keydown", e => e.key === "Escape" && close());
    textArea.addEventListener("copy", close);
    textArea.addEventListener("cut", close);

    const message = preferUI ?
        "Copy or press <Escape> to close.\n\n" :
        "Can't access clipboard on an unsafe site. Copy or press <Escape> to close.\n\n";

    textArea.value = message + content;
    document.body.appendChild(textArea);
    textArea.setSelectionRange(message.length, textArea.value.length);
    textArea.focus();
}

function isUrl(str) {
    try {
        let url = new URL(str);
        return ["http:", "https:"].includes(url.protocol);
    } catch {
        return false;
    }
}

document.addEventListener("keydown", async e => {
    if (!hotkey(e)) {
        return;
    }

    let selection = window.getSelection();
    let allAnchors = Array.from(document.getElementsByTagName("a"));

    let links = allAnchors
        .filter(anchor => selection.containsNode(anchor, true))
        .map(anchor => anchor.href)
        .filter(href => href && isUrl(href));

    if (links.length) {
        await copy(links.join("\n"));
    } else {
        console.log("No links selected.");
    }
});