feat: implement browser extension UI with WebAssembly integration

extension/public/background/index.js

@@ -0,0 +1,102 @@
+// Background service worker for Modular Vault Extension
+// Handles session, keypair, and WASM logic
+
+// We need to use dynamic imports for service workers in MV3
+let wasmModule;
+let init;
+let wasm;
+let wasmReady = false;
+
+// Initialize WASM on startup with dynamic import
+async function loadWasm() {
+  try {
+    // Using importScripts for service worker
+    const wasmUrl = chrome.runtime.getURL('wasm/wasm_app.js');
+    wasmModule = await import(wasmUrl);
+    init = wasmModule.default;
+    wasm = wasmModule;
+    
+    // Initialize WASM with explicit WASM file path
+    await init(chrome.runtime.getURL('wasm/wasm_app_bg.wasm'));
+    wasmReady = true;
+    console.log('WASM initialized in background');
+  } catch (error) {
+    console.error('Failed to initialize WASM:', error);
+  }
+}
+
+// Start loading WASM
+loadWasm();
+
+chrome.runtime.onMessage.addListener(async (request, sender, sendResponse) => {
+  if (!wasmReady) {
+    sendResponse({ error: 'WASM not ready' });
+    return true;
+  }
+  // Session unlock/create
+  if (request.action === 'init_session') {
+    try {
+      const result = await wasm.init_session(request.keyspace, request.password);
+      // Persist current session info
+      await chrome.storage.local.set({ currentKeyspace: request.keyspace });
+      sendResponse({ ok: true });
+    } catch (e) {
+      sendResponse({ error: e.message });
+    }
+    return true;
+  }
+  // Lock session
+  if (request.action === 'lock_session') {
+    try {
+      wasm.lock_session();
+      await chrome.storage.local.set({ currentKeyspace: null });
+      sendResponse({ ok: true });
+    } catch (e) {
+      sendResponse({ error: e.message });
+    }
+    return true;
+  }
+  // Add keypair
+  if (request.action === 'add_keypair') {
+    try {
+      const keyId = await wasm.add_keypair('Secp256k1', null);
+      let keypairs = (await chrome.storage.local.get(['keypairs'])).keypairs || [];
+      keypairs.push({ id: keyId, label: `Secp256k1-${keypairs.length + 1}` });
+      await chrome.storage.local.set({ keypairs });
+      sendResponse({ keyId });
+    } catch (e) {
+      sendResponse({ error: e.message });
+    }
+    return true;
+  }
+  // Select keypair
+  if (request.action === 'select_keypair') {
+    try {
+      await wasm.select_keypair(request.keyId);
+      await chrome.storage.local.set({ selectedKeypair: request.keyId });
+      sendResponse({ ok: true });
+    } catch (e) {
+      sendResponse({ error: e.message });
+    }
+    return true;
+  }
+  // Sign
+  if (request.action === 'sign') {
+    try {
+      // Convert plaintext to Uint8Array
+      const encoder = new TextEncoder();
+      const msgBytes = encoder.encode(request.message);
+      const signature = await wasm.sign(msgBytes);
+      sendResponse({ signature });
+    } catch (e) {
+      sendResponse({ error: e.message });
+    }
+    return true;
+  }
+  // Query status
+  if (request.action === 'get_status') {
+    const { currentKeyspace, keypairs, selectedKeypair } = await chrome.storage.local.get(['currentKeyspace', 'keypairs', 'selectedKeypair']);
+    sendResponse({ currentKeyspace, keypairs: keypairs || [], selectedKeypair });
+    return true;
+  }
+});