theseus/bcnr-preload.js

// bcnr-preload.js — session-wide preload that installs `window.bcnr` on every
// page (regular tabs, popups, chrome/settings/etc). Reads only — no signing,
// no wallet unlock, no permission prompts. These four methods query the same
// resolver Theseus already runs for its address bar; nothing about the local
// user leaks, so no origin gate is needed for this surface.
//
// Sequencing: registered via `session.defaultSession.setPreloads([...])` in
// main.js at whenReady, which runs BEFORE per-WebContentsView preloads (home,
// settings, popover, etc.), so those preloads still install their own bridges
// on top of `window.bcnr`. See DESIGN-integrated-wallet.md §3 for the full
// API surface.
const { contextBridge, ipcRenderer } = require("electron");

// Every method returns a Promise; a name that fails to resolve or isn't
// registered comes back as `null` (not an error) so page code can treat
// "no such name" as data, not an exception. `getBcnrTlds` always returns
// an array — even the seed ["bch"] before the on-chain list has landed.
contextBridge.exposeInMainWorld("bcnr", {
  resolveName:      (name) => ipcRenderer.invoke("bcnr:resolveName", name),
  isRegistered:     (name) => ipcRenderer.invoke("bcnr:isRegistered", name),
  getBcnrTlds:      ()     => ipcRenderer.invoke("bcnr:getBcnrTlds"),
  getRecordVersion: (name) => ipcRenderer.invoke("bcnr:getRecordVersion", name),
  // Owner-signed DNS records (A/AAAA/MX/TXT/CNAME/NS) published beside the
  // name's Sia content and verified by the gateway against the current NFT
  // holder. `{ name, dns, seq, updatedAt, owner }`, or null when the name is
  // unregistered or has published no manifest. Waits ≤ 3 s for a fetch.
  dnsRecords:       (name) => ipcRenderer.invoke("bcnr:dnsRecords", name),
  // Diagnostic — the eTLD+1 permission origin Theseus computes for THIS page.
  // dApp devs use this to see how their subdomains bucket under one grant.
  // Returns null for opaque origins (data:, blob:) which never hold grants.
  getOrigin:        ()     => ipcRenderer.invoke("bcnr:getOrigin"),
  // One-click install of a community extension by catalog id (what
  // theseus.x/extensions' Install button calls). The page names an id only;
  // Theseus fetches the catalog itself, asks the user in a native dialog,
  // verifies the publisher signature against the name's owner and installs.
  // Resolves `{ ok, version, publisher }` or `{ ok:false, error }` (also
  // "cancelled"). Pages can feature-detect it: absent on older builds.
  installExtension: (id)   => ipcRenderer.invoke("bcnr:installExtension", String(id || "")),
});

// Install-as-app relay. Theseus fires a synthetic `beforeinstallprompt` in
// pages whose manifest is installable (webapps.js); the page's prompt()
// dispatches a DOM event that this isolated world hears, asks main for the
// install dialog, and answers with another DOM event. Nothing is exposed
// on window; the page only ever sees Chrome's event shape. Top frame only.
try {
  if (window.top === window) {
    document.addEventListener("theseus:webapp-prompt", () => {
      ipcRenderer.invoke("webapp-prompt").then((r) => {
        document.dispatchEvent(new Event(r === "accepted" ? "theseus:webapp-accepted" : "theseus:webapp-dismissed"));
      }).catch(() => { try { document.dispatchEvent(new Event("theseus:webapp-dismissed")); } catch {} });
    });
  }
} catch {}