theseus/sidebar-preload.js

// Preload shared by every add-on sidebar panel. Exposes a small, safe
// surface to the add-on's HTML. Main-side handlers derive the add-on
// identity from the sender's URL (the panel is always loaded from
// somewhere inside <userData>/addons/<id>/), so a random page that
// happens to see the API shape can't touch another add-on's storage.
const { contextBridge, ipcRenderer } = require("electron");
contextBridge.exposeInMainWorld("silentmode", {
  storage: {
    get: (key, fallback = null) => ipcRenderer.invoke("addon-storage-get", key, fallback),
    set: (key, value)           => ipcRenderer.invoke("addon-storage-set", key, value),
    all: ()                     => ipcRenderer.invoke("addon-storage-all"),
  },
  // Ask main which panel is currently visible — panels may want to
  // suspend expensive work when hidden.
  onVisibility: (cb) => ipcRenderer.on("sidebar-visibility", (_e, visible) => cb(!!visible)),
});

// Sidebar resize grip. Injected into every panel automatically so panel
// authors don't have to reinvent it. A thin strip along the LEFT edge
// (the boundary between the tab area and the sidebar) accepts mousedown
// and streams drag deltas to main until mouseup. Main clamps the width
// to [200, 800] and persists it in settings.sidebarWidth.
window.addEventListener("DOMContentLoaded", () => {
  const grip = document.createElement("div");
  grip.setAttribute("aria-label", "Resize sidebar");
  grip.style.cssText = [
    "position:fixed", "left:0", "top:0", "bottom:0",
    "width:5px", "cursor:col-resize", "z-index:2147483647",
    "background:transparent",
  ].join(";");
  // A faint highlight on hover so the affordance is visible.
  grip.addEventListener("mouseenter", () => { grip.style.background = "rgba(214,255,61,.20)"; });
  grip.addEventListener("mouseleave", () => { if (!dragging) grip.style.background = "transparent"; });
  document.body.appendChild(grip);
  let dragging = false;
  grip.addEventListener("mousedown", (e) => {
    if (e.button !== 0) return;
    e.preventDefault();
    dragging = true;
    document.body.style.userSelect = "none";
    grip.style.background = "rgba(214,255,61,.35)";
  });
  window.addEventListener("mousemove", (e) => {
    if (!dragging) return;
    // Moving cursor LEFT = grow sidebar width. movementX is negative left.
    if (e.movementX !== 0) ipcRenderer.invoke("sidebar-drag", -e.movementX);
  });
  const stop = () => {
    if (!dragging) return;
    dragging = false;
    document.body.style.userSelect = "";
    grip.style.background = "transparent";
  };
  window.addEventListener("mouseup", stop);
  window.addEventListener("mouseleave", stop);
});