2 files changed, 68 insertions, 5 deletions

diff --git a/lib/passkey.ts b/lib/passkey.ts
index 573c62b..81a21a5 100644
--- a/lib/passkey.ts
+++ b/lib/passkey.ts
@@ -1,8 +1,14 @@
+"use client";
+
+import { Platform } from "react-native";
+import * as SecureStore from "expo-secure-store";
+import type { AsyncRes } from "./types";
+
 const PASSKEY_CREDENTIAL_ID_KEY = "urbit_wallet_passkey_id";
 const RELYING_PARTY_ID = "wallet.urbit.org"; // Change this to your domain
 const RELYING_PARTY_NAME = "Urbit Wallet";
 
-async function createPasskey() {
+export async function createPasskey(): AsyncRes<PublicKeyCredential> {
   const pkok =
     await window.PublicKeyCredential.isUserVerifyingPlatformAuthenticatorAvailable();
   console.log({ pkok });
@@ -117,15 +123,70 @@ async function createPasskey() {
 
     if (credential) {
       // Store the credential ID for later use
-      // await SecureStore.setItemAsync(PASSKEY_CREDENTIAL_ID_KEY, credential.id);
+      await SecureStore.setItemAsync(PASSKEY_CREDENTIAL_ID_KEY, credential.id);
 
       console.log("Passkey created successfully", credential.id);
-      return true;
+      return { ok: credential };
     }
 
-    return false;
+    return { error: "Failed to create passkey" };
   } catch (error) {
     console.error("Error creating passkey:", error);
-    return false;
+    return { error: `${error}` };
+  }
+}
+
+export async function authenticateWithPasskey(): AsyncRes<PublicKeyCredential> {
+  // if (Platform.OS !== "web") {
+  //   return false;
+  // }
+
+  try {
+    const credentialId = await SecureStore.getItemAsync(
+      PASSKEY_CREDENTIAL_ID_KEY,
+    );
+
+    if (!credentialId) {
+      console.log("No passkey found");
+      return { error: "No passkey found" };
+    }
+
+    // Generate a random challenge
+    const challenge = new Uint8Array(32);
+    crypto.getRandomValues(challenge);
+
+    const getCredentialOptions: CredentialRequestOptions = {
+      publicKey: {
+        challenge,
+        rpId:
+          window.location.hostname === "localhost"
+            ? "localhost"
+            : RELYING_PARTY_ID,
+        allowCredentials: [
+          {
+            id: Uint8Array.from(atob(credentialId), (c) => c.charCodeAt(0)),
+            type: "public-key",
+            transports: ["internal", "hybrid"] as AuthenticatorTransport[],
+          },
+        ],
+        userVerification: "preferred",
+        timeout: 60000,
+      },
+    };
+
+    const credential = (await navigator.credentials.get(
+      getCredentialOptions,
+    )) as PublicKeyCredential;
+
+    if (credential) {
+      // In a production app, you would send the assertion to your server
+      // to verify it. For this demo, we're just checking if we got a credential.
+      console.log("Passkey authentication successful");
+      return { ok: credential };
+    }
+
+    return { error: "failed to generate creds" };
+  } catch (error) {
+    return { error: `${error}` };
   }
 }
diff --git a/lib/types.ts b/lib/types.ts
new file mode 100644
index 0000000..a22e8be
--- /dev/null
+++ b/lib/types.ts
@@ -0,0 +1,2 @@
+export type Result<T> = { ok: T } | { error: string };
+export type AsyncRes<T> = Promise<Result<T>>;