Academic Article Unlocker

Easily access open-access versions of academic articles with the click of a button. Say goodbye to paywalls and hello to knowledge.

Tendrás que instalar una extensión para tu navegador como Tampermonkey, Greasemonkey o Violentmonkey si quieres utilizar este script.

You will need to install an extension such as Tampermonkey to install this script.

Tendrás que instalar una extensión como Tampermonkey o Violentmonkey para instalar este script.

Necesitarás instalar una extensión como Tampermonkey o Userscripts para instalar este script.

Tendrás que instalar una extensión como Tampermonkey antes de poder instalar este script.

Necesitarás instalar una extensión para administrar scripts de usuario si quieres instalar este script.

(Ya tengo un administrador de scripts de usuario, déjame instalarlo)

Tendrás que instalar una extensión como Stylus antes de poder instalar este script.

Tendrás que instalar una extensión como Stylus antes de poder instalar este script.

Tendrás que instalar una extensión como Stylus antes de poder instalar este script.

Para poder instalar esto tendrás que instalar primero una extensión de estilos de usuario.

Para poder instalar esto tendrás que instalar primero una extensión de estilos de usuario.

Para poder instalar esto tendrás que instalar primero una extensión de estilos de usuario.

(Ya tengo un administrador de estilos de usuario, déjame instalarlo)

  // ==UserScript==
  // @name        Academic Article Unlocker
  // @match       *://*/doi/*
  // @match       *://*/doiLanding*
  // @match       *://*/*?doi=*
  // @match       *://*.nlm.nih.gov/*
  // @match       *://www.nature.com/articles/*
  // @match       *://zenodo.org/record/*
  // @match       *://www.sciencedirect.com/science/article/*
  // @match       *://ieeexplore.ieee.org/document/*
  // @match       *://www.epistemonikos.org/*/documents/*
  // @match       *://psycnet.apa.org/record/*
  // @match       *://www.cdc.gov/mmwr/volumes/*
  // @match       *://iastatedigitalpress.com/jlsc/*
  // @match       *://www.researchgate.net/publication/*
  // @match       *://www.thelancet.com/journals/*
  // @match       *://www.nber.org/papers/*
  // @match       *://psycnet.apa.org/record/*
  // @match       *://www.cell.com/*/fulltext/*
  // @match       *://pubs.rsc.org/*/articlelanding/*
  // @match       *://*.biomedcentral.com/articles/*
  // @match       *://nowpublishers.com/article/*
  // @match       *://jamanetwork.com/*
  // @match       *://www.bmj.com/content/*
  // @match       *://*.aspetjournals.org/content/*
  // @match       *://philpapers.org/rec/*
  // @match       *://www.jci.org/articles/*
  // @match       *://www.computer.org/csdl/*
  // @match       *://muse.jhu.edu/pub/*
  // @match       *://muse.jhu.edu/article/*
  // @match       *://www.deepdyve.com/lp/*
  // @match       *://www.degruyter.com/document/doi/*
  // @match       *://www.nli.org.il/en/articles/*
  // @match       *://link.springer.com/*
  // @match       *://www.jstor.org/stable/*
  // @match       *://www.frontiersin.org/journals/*
  // @match       *://www.cambridge.org/core/journals/*
  // @match       *://annalsofglobalhealth.org/*
  // @exclude     *://annas-archive.org/*
  // @grant       none
  // @version     3.1.7
  // @author      NoUser
  // @description Easily access open-access versions of academic articles with the click of a button. Say goodbye to paywalls and hello to knowledge.
  // @run-at      document-end
  // @namespace   https://greasyfork.org/en/scripts/459616-academic-article-unlocker
  // @homepage    https://greasyfork.org/en/scripts/459616-academic-article-unlocker
  // @license     MIT
  // ==/UserScript==

const ENABLE_SCIHUB = true; // Set to false to hide the Sci-Hub button
const SCIHUB_URL = "https://sci-hub.ru/"; // Change to your preferred Sci-Hub mirror

(function () {
  "use strict";

  function findDoi() {
    for (const meta of document.querySelectorAll("meta")) {
      if (
        meta.name &&
        [
          "citation_doi",
          "doi",
          "dc.doi",
          "dc.identifier",
          "prism.doi",
        ].includes(meta.name.toLowerCase())
      ) {
        const c = meta.content;
        if (c && c.trim().startsWith("10.")) return c.trim();
      }
    }
    const els = document.querySelectorAll("[data-doi]");
    if (els.length === 1) {
      const d = els[0].getAttribute("data-doi");
      if (d && d.trim().startsWith("10.")) return d.trim();
    }
    const m = window.location.href.match(
      /\b(10\.\d{4,9}\/[-._;()/:A-Z0-9]+)\b/i
    );
    return m ? m[1] : null;
  }

  async function getOpenAccessStatus() {
    const doi = findDoi();
    if (!doi) return {};
    try {
      const res = await fetch(
        `https://api.unpaywall.org/v2/${doi}[email protected]`
      );
      if (!res.ok) return {};
      return await res.json();
    } catch {
      return {};
    }
  }

  function createButtonContainer() {
    const container = document.createElement("div");
    container.id = "article-unlocker-container";
    const shadow = container.attachShadow({ mode: "closed" });
    const style = document.createElement("style");
    style.textContent = `
      :host {
        position: fixed;
        right: 0;
        bottom: 0;
        z-index: 9999;
        font-family: system-ui, sans-serif;
      }
      .unlocker-wrapper {
        background: #fcfdfe;
        border: 1.5px solid #e3e7ee;
        border-radius: 18px 18px 0 0;
        box-shadow: 0 0 16px 0 rgba(60,72,90,0.13);
        min-width: 2px;
        max-width: 320px;
        margin: 0 12px 12px 0;
        display: flex;
        flex-direction: column;
        align-items: stretch;
        transition: transform 0.3s cubic-bezier(.4,1.4,.6,1), box-shadow 0.2s;
        transform: translateY(0);
      }
      .unlocker-wrapper.collapsed {
        box-shadow: none;
        background: transparent;
        border: none;
        min-width: 0;
        max-width: none;
        margin: 0 16px 8px 0;
        transform: translateY(calc(100% - 30px));
        pointer-events: auto;
      }
      .toggle-button {
        background: none;
        border: none;
        cursor: pointer;
        padding: 8px 0;
        margin: 0 auto;
        display: flex;
        align-items: center;
        justify-content: center;
        width: 100%;
        transition: background 0.15s;
        z-index: 2;
        position: relative;
      }
      .toggle-arrow {
        width: 40px;
        height: 40px;
        transition: transform 0.2s;
        display: block;
        margin: 0 auto;
      }
      .unlocker-wrapper.collapsed .toggle-arrow {
        transform: rotate(180deg);
      }
      .button-group {
        display: flex;
        flex-direction: column;
        padding: 8px 0 14px 0;
        transition: max-height 0.3s, opacity 0.2s;
        max-height: 800px;
        opacity: 1;
      }
      .unlocker-wrapper.collapsed .button-group {
        max-height: 0;
        opacity: 0;
        pointer-events: none;
        padding: 0;
      }
      .access-link {
        display: flex;
        align-items: center;
        gap: 12px;
        padding: 12px 18px;
        margin: 0 10px 6px 10px;
        text-decoration: none;
        font-size: 18px;
        font-weight: 600;
        color: #2d3748;
        border-radius: 10px;
        transition: background 0.13s, text-decoration 0.13s;
      }
      .access-link:visited {
        color: #6b7280;
      }
      .access-link:hover,
      .access-link:focus {
        background: #f2f6fa;
        text-decoration: underline;
      }
      .access-link img {
        width: 45px;
        height: 45px;
        flex-shrink: 0;
      }
      .scihub-link span { color: #c00; }
      .unpaywall-link span { color: #2CBB4C; }
    `;
    const wrapper = document.createElement("div");
    wrapper.className = "unlocker-wrapper";
    const toggle = document.createElement("button");
    toggle.className = "toggle-button";
    toggle.title = "Show/hide unlocker";
    toggle.innerHTML = `
      <svg class="toggle-arrow" viewBox="0 0 24 24">
        <polygon points="12,16 6,9 18,9" fill="#6c757d"/>
      </svg>`;
    const group = document.createElement("div");
    group.className = "button-group";
    wrapper.append(toggle, group);
    shadow.append(style, wrapper);
    document.body.append(container);
    toggle.addEventListener("click", () => {
      wrapper.classList.toggle("collapsed");
    });
    return group;
  }

  const buttonGroup = createButtonContainer();

  function createLink(icon, label, cls, url) {
    const a = document.createElement("a");
    a.className = `access-link ${cls}`;
    a.href = url;
    a.target = "_blank";
    a.rel = "noopener noreferrer";
    a.innerHTML = `<img src="${icon}" alt=""><span>${label}</span>`;
    buttonGroup.appendChild(a);
  }

  const scIcon =
    "data:image/svg+xml;base64,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";
  const unIcon =
    "data:image/svg+xml;base64,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";

  (async function () {
    if (ENABLE_SCIHUB) {
      createLink(
        scIcon,
        "Sci‑Hub",
        "scihub-link",
        SCIHUB_URL + window.location.href
      );
    }
    const data = await getOpenAccessStatus();
    if (data.best_oa_location?.url) {
      createLink(unIcon, "Unpaywall", "unpaywall-link", data.best_oa_location.url);
    }
  })();
})();