Adding native features with Claude Code and the WebViewGold JavaScript bridge

// src/lib/native.ts
export function isNativeApp() {
  return typeof navigator !== "undefined" && navigator.userAgent.indexOf("WebViewGoldApp") !== -1;
}

export function callNative(scheme) {
  if (!isNativeApp()) return false;
  window.location.href = scheme;
  return true;
}

// Wait for a variable the wrapper injects, e.g. onesignalplayerid or nativePushEnabled
export function readInjected(name, timeoutMs) {
  return new Promise(function (resolve, reject) {
    var started = Date.now();
    (function check() {
      if (typeof window[name] !== "undefined") return resolve(window[name]);
      if (Date.now() - started > (timeoutMs || 3000)) return reject(new Error(name + " not injected"));
      setTimeout(check, 100);
    })();
  });
}

import { callNative, readInjected } from "./native";

// 1. Ask at the right moment (after onboarding, not on first launch)
export function askForPush() {
  return callNative("registerpush://");
}

// 2. Is push currently allowed? Sets window.nativePushEnabled
export async function isPushEnabled() {
  if (!callNative("checkNativePushPermissions://")) return null;
  return readInjected("nativePushEnabled", 2000);
}

// 3. Store the OneSignal subscription ID on the user so the server can target this device
export async function syncPushId(saveToProfile) {
  if (!callNative("getonesignalplayerid://")) return;
  var id = await readInjected("onesignalplayerid", 3000);
  await saveToProfile(id);
}

// 4. A local reminder in two hours, no push service needed
export function scheduleLocalReminder(title, message, url) {
  var seconds = 2 * 60 * 60;
  callNative("sendlocalpushmsg://push.send?s=" + seconds + "=msg!" + message + "&!#" + title + "&!#" + url);
}

import { callNative } from "./native";

export function requireBiometrics(onPass, onFallback) {
  window.onBioAuthSuccess = function () { onPass(); };
  window.onBioAuthFailure = function (errorCode, errorMessage) {
    console.warn("bioauth failed", errorCode, errorMessage);
    onFallback();
  };
  window.onBioAuthUnavailable = function () { onFallback(); };
  if (!callNative("bioauth://")) onFallback(); // browser: use the password re-entry instead
}

// Security note from the documentation: treat the success callback as a UI gate only.
// Keep sensitive actions behind a server-side session check as well.