feat: Unified BIP321 URI and 3-way toggle for payments

app/build.gradle.kts

@@ -134,7 +134,7 @@ dependencies {
     implementation("com.google.zxing:core:3.5.3")
 
     // CDK Kotlin bindings
-    implementation("org.cashudevkit:cdk-kotlin:0.15.1")
+    implementation("org.cashudevkit:cdk-kotlin:0.15.2-rc.0")
 
     // ML Kit Barcode Scanning
     implementation("com.google.mlkit:barcode-scanning:17.3.0")

app/src/main/java/com/electricdreams/numo/core/cashu/CashuWalletManager.kt

@@ -17,6 +17,9 @@ import org.cashudevkit.WalletDatabaseImpl
 import org.cashudevkit.NoPointer
 import org.cashudevkit.WalletSqliteDatabase
 import org.cashudevkit.WalletRepository
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.asStateFlow
 import org.cashudevkit.generateMnemonic
 
 /**
@@ -28,6 +31,10 @@ import org.cashudevkit.generateMnemonic
  * The wallet's mnemonic (seed phrase) and SQLite database are both
  * persisted so that balances survive app restarts.
  */
+enum class WalletState {
+    UNINITIALIZED, LOADING, READY, ERROR
+}
+
 object CashuWalletManager : MintManager.MintChangeListener {
 
     private const val TAG = "CashuWalletManager"
@@ -43,9 +50,8 @@ object CashuWalletManager : MintManager.MintChangeListener {
     @Volatile
     private var wallet: WalletRepository? = null
 
-    @Volatile
-    var isWalletLoading: Boolean = false
-        private set
+    private val _walletState = MutableStateFlow(WalletState.UNINITIALIZED)
+    val walletState: StateFlow<WalletState> = _walletState.asStateFlow()
 
     /** Initialize from ModernPOSActivity. Safe to call multiple times. */
     fun init(context: Context) {
@@ -164,6 +170,7 @@ object CashuWalletManager : MintManager.MintChangeListener {
 
         database = db
         wallet = newWallet
+            _walletState.value = WalletState.READY
 
         Log.d(TAG, "Wallet restore complete. Restored ${mints.size} mints.")
 
@@ -400,7 +407,7 @@ object CashuWalletManager : MintManager.MintChangeListener {
      * Runs on our IO coroutine scope.
      */
     private suspend fun rebuildWallet(mints: List<String>) {
-        isWalletLoading = true
+        _walletState.value = WalletState.LOADING
         try {
             // Close any previous instances
             closeResources()
@@ -446,15 +453,15 @@ object CashuWalletManager : MintManager.MintChangeListener {
 
             database = db
             wallet = newWallet
+            _walletState.value = WalletState.READY
 
             Log.d(TAG, "Initialized WalletRepository with ${mints.size} mints; DB=${dbFile.absolutePath}")
 
             // Notify UI that wallet is ready
             BalanceRefreshBroadcast.send(appContext, "wallet_initialized")
         } catch (t: Throwable) {
             Log.e(TAG, "Failed to initialize WalletRepository", t)
-        } finally {
-            isWalletLoading = false
+            _walletState.value = WalletState.ERROR
         }
     }
 

app/src/main/java/com/electricdreams/numo/feature/history/PaymentsHistoryActivity.kt

@@ -136,7 +136,7 @@ class PaymentsHistoryActivity : AppCompatActivity() {
     }
 
     private fun loadBalance() {
-        if (CashuWalletManager.isWalletLoading) {
+        if (CashuWalletManager.walletState.value == com.electricdreams.numo.core.cashu.WalletState.LOADING) {
             binding.balanceFiat?.text = "..."
             binding.balanceSats?.visibility = View.GONE
             return

app/src/main/java/com/electricdreams/numo/ndef/CashuPaymentHelper.kt

@@ -38,6 +38,11 @@ object CashuPaymentHelper {
      * Structured result of validating a Cashu token against an expected
      * amount and the merchant's allowed mint list.
      */
+        data class GeneratedPaymentRequest(
+        val original: String,
+        val bech32: String
+    )
+
     sealed class TokenValidationResult {
         /** The provided string was not a valid Cashu token. */
         object InvalidFormat : TokenValidationResult()
@@ -69,7 +74,7 @@ object CashuPaymentHelper {
         amount: Long,
         description: String?,
         allowedMints: List<String>?,
-    ): String? {
+    ): GeneratedPaymentRequest? {
         return try {
             val paymentRequest = PaymentRequest().apply {
                 this.amount = Optional.of(amount)
@@ -92,15 +97,23 @@ object CashuPaymentHelper {
 
             val encoded = paymentRequest.encode()
             Log.d(TAG, "Created payment request: $encoded")
-            encoded
+            try {
+                val cdkRequest = org.cashudevkit.PaymentRequest.fromString(encoded)
+                val bech32 = cdkRequest.toBech32String()
+                Log.d(TAG, "Converted to bech32: $bech32")
+                GeneratedPaymentRequest(encoded, bech32)
+            } catch (e: Throwable) {
+                Log.e(TAG, "Error converting to bech32, returning CREQA format: ${e.message}", e)
+                GeneratedPaymentRequest(encoded, encoded)
+            }
         } catch (e: Exception) {
             Log.e(TAG, "Error creating payment request: ${e.message}", e)
             null
         }
     }
 
     @JvmStatic
-    fun createPaymentRequest(amount: Long, description: String?): String? =
+    fun createPaymentRequest(amount: Long, description: String?): GeneratedPaymentRequest? =
         createPaymentRequest(amount, description, null)
 
     @JvmStatic
@@ -109,7 +122,7 @@ object CashuPaymentHelper {
         description: String?,
         allowedMints: List<String>?,
         nprofile: String,
-    ): String? {
+    ): GeneratedPaymentRequest? {
         return try {
             val paymentRequest = PaymentRequest().apply {
                 this.amount = Optional.of(amount)
@@ -145,7 +158,15 @@ object CashuPaymentHelper {
 
             val encoded = paymentRequest.encode()
             Log.d(TAG, "Created Nostr payment request: $encoded")
-            encoded
+            try {
+                val cdkRequest = org.cashudevkit.PaymentRequest.fromString(encoded)
+                val bech32 = cdkRequest.toBech32String()
+                Log.d(TAG, "Converted Nostr to bech32: $bech32")
+                GeneratedPaymentRequest(encoded, bech32)
+            } catch (e: Throwable) {
+                Log.e(TAG, "Error converting to bech32, returning CREQA format: ${e.message}", e)
+                GeneratedPaymentRequest(encoded, encoded)
+            }
         } catch (e: Exception) {
             Log.e(TAG, "Error creating Nostr payment request: ${e.message}", e)
             null
@@ -234,7 +255,7 @@ object CashuPaymentHelper {
 
     @JvmStatic
     fun isCashuPaymentRequest(text: String?): Boolean =
-        text != null && text.startsWith("creqA")
+        text != null && (text.startsWith("creqA") || text.lowercase().startsWith("creqb"))
 
     // === Validation using CDK Token ========================================
 

app/src/main/java/com/electricdreams/numo/ndef/NdefHostCardEmulationService.java

@@ -43,9 +43,10 @@ public class NdefHostCardEmulationService extends HostApduService {
 
     // NFC reading state tracking
     private boolean isNfcReading = false;
+    private boolean isNfcWriting = false; // Tracks if payer actually started writing
     private Handler nfcTimeoutHandler;
     private Runnable nfcTimeoutRunnable;
-    private static final long NFC_TIMEOUT_MS = 2000; // 2 seconds
+    private static final long NFC_TIMEOUT_MS = 3500; // 3.5 seconds
 
     /**
      * Callback interface for Cashu payments
@@ -54,7 +55,7 @@ public interface CashuPaymentCallback {
         void onCashuTokenReceived(String token);
         void onCashuPaymentError(String errorMessage);
         void onNfcReadingStarted();
-        void onNfcReadingStopped();
+        void onNfcReadingStopped(boolean failedInMiddleOfTransaction);
     }
 
     /**
@@ -76,7 +77,7 @@ public void onCreate() {
             @Override
             public void run() {
                 Log.i(TAG, "NFC reading timeout - no APDU received for " + NFC_TIMEOUT_MS + "ms");
-                stopNfcReading();
+                stopNfcReading(false);
             }
         };
 
@@ -91,7 +92,7 @@ public void onNdefMessageReceived(String message) {
                         Log.i(TAG, "Message content: " + message);
 
                         // Stop NFC reading indicator since we received the complete message
-                        stopNfcReading();
+                        stopNfcReading(true);
 
                         // First try to extract a Cashu token from the message
                         String cashuToken = CashuPaymentHelper.extractCashuToken(message);
@@ -169,10 +170,20 @@ public byte[] processCommandApdu(byte[] commandApdu, Bundle extras) {
                 Log.i(TAG, "Command: " + description);
             }
 
-            // Start/reset NFC reading indicator when we receive APDU commands
-            // Only track reading if we have a payment callback set (meaning we're expecting a payment)
+            // Start or reset NFC reading indicator for any APDU command when a payment is expected
             if (paymentCallback != null) {
                 startOrResetNfcReading();
+
+                // Track if the payer started writing data (UPDATE BINARY)
+                if (commandApdu != null && commandApdu.length >= 2) {
+                    // UPDATE BINARY header is 00 D6
+                    if (commandApdu[0] == (byte)0x00 && commandApdu[1] == (byte)0xD6) {
+                        if (!isNfcWriting) {
+                            Log.i(TAG, "Payer started writing data (UPDATE BINARY received)");
+                            isNfcWriting = true;
+                        }
+                    }
+                }
             }
 
             // Try to process with the NDEF processor
@@ -240,7 +251,7 @@ public void clearPaymentRequest() {
         this.expectedAmount = 0;
 
         // Stop NFC reading if active
-        stopNfcReading();
+        stopNfcReading(true); // Don't trigger failure UI on manual clear
 
         if (ndefProcessor != null) {
             ndefProcessor.setMessageToSend("");
@@ -374,6 +385,7 @@ private void startOrResetNfcReading() {
         }
 
         // Reset the timeout - cancel any pending timeout and schedule a new one
+        Log.d(TAG, "Resetting NFC reading timeout timer (" + NFC_TIMEOUT_MS + "ms)");
         nfcTimeoutHandler.removeCallbacks(nfcTimeoutRunnable);
         nfcTimeoutHandler.postDelayed(nfcTimeoutRunnable, NFC_TIMEOUT_MS);
     }
@@ -382,18 +394,23 @@ private void startOrResetNfcReading() {
      * Stop the NFC reading indicator
      * Called when the NDEF message is received or timeout occurs
      */
-    private void stopNfcReading() {
+    private void stopNfcReading(boolean isSuccess) {
         if (isNfcReading) {
-            Log.i(TAG, "NFC reading stopped");
+            Log.i(TAG, "NFC reading stopped. Was writing data: " + isNfcWriting + " Success: " + isSuccess);
             isNfcReading = false;
 
             // Cancel any pending timeout
+            Log.d(TAG, "Cancelling NFC reading timeout timer");
             nfcTimeoutHandler.removeCallbacks(nfcTimeoutRunnable);
 
-            // Notify callback
-            if (paymentCallback != null) {
-                paymentCallback.onNfcReadingStopped();
+            // Notify callback ONLY if it's NOT a success.
+            // If it is a success, the higher-level logic handles the UI transition via onCashuTokenReceived.
+            if (paymentCallback != null && !isSuccess) {
+                paymentCallback.onNfcReadingStopped(isNfcWriting);
             }
+
+            // Reset writing flag for next session
+            isNfcWriting = false;
         }
     }
 

app/src/main/java/com/electricdreams/numo/payment/LightningMintHandler.kt

@@ -1,6 +1,8 @@
 package com.electricdreams.numo.payment
 
+import android.content.Context
 import android.util.Log
+import com.electricdreams.numo.R
 import com.electricdreams.numo.core.cashu.CashuWalletManager
 import com.google.gson.Gson
 import com.google.gson.JsonObject
@@ -43,6 +45,7 @@ import kotlin.coroutines.resumeWithException
  * @param uiScope Coroutine scope for UI callbacks
  */
 class LightningMintHandler(
+    private val context: Context,
     private val preferredMint: String?,
     private val allowedMints: List<String>,
     private val uiScope: CoroutineScope,
@@ -51,10 +54,11 @@ class LightningMintHandler(
 ) {
     // Secondary constructor to maintain compatibility
     constructor(
+        context: Context,
         preferredMint: String?,
         allowedMints: List<String>,
         uiScope: CoroutineScope
-    ) : this(preferredMint, allowedMints, uiScope, Dispatchers.IO)
+    ) : this(context, preferredMint, allowedMints, uiScope, Dispatchers.IO)
     /**
      * Callback interface for Lightning mint events.
      */
@@ -149,7 +153,7 @@ class LightningMintHandler(
 
                 Log.d(TAG, "Requesting Lightning mint quote from ${mintUrl.url} for $paymentAmount sats")
                 val mintWallet = wallet.getWallet(mintUrl, CurrencyUnit.Sat)
-                val quote = mintWallet?.mintQuote(org.cashudevkit.PaymentMethod.Bolt11, quoteAmount, "Numo POS payment of $paymentAmount sats", null)
+                val quote = mintWallet?.mintQuote(org.cashudevkit.PaymentMethod.Bolt11, quoteAmount, context.getString(R.string.payment_request_lightning_description, paymentAmount), null)
                     ?: throw Exception("Failed to get wallet for mint: ${mintUrl.url}")
                 mintQuote = quote
 

app/src/main/java/com/electricdreams/numo/payment/NostrPaymentHandler.kt

@@ -1,6 +1,7 @@
 package com.electricdreams.numo.payment
 
 import android.content.Context
+import com.electricdreams.numo.R
 import android.util.Log
 import com.electricdreams.numo.feature.history.PaymentsHistoryActivity
 import com.electricdreams.numo.core.util.MintManager
@@ -51,6 +52,10 @@ class NostrPaymentHandler(
     var paymentRequest: String? = null
         private set
 
+    /** The generated payment request string (bech32) */
+    var paymentRequestBech32: String? = null
+        private set
+
     /**
      * Start a new Nostr payment flow with fresh keys.
      *
@@ -136,7 +141,7 @@ class NostrPaymentHandler(
         // Create payment request with Nostr transport
         val request = CashuPaymentHelper.createPaymentRequestWithNostr(
             paymentAmount,
-            "Payment of $paymentAmount sats",
+            context.getString(R.string.payment_request_default_description, paymentAmount),
             mintsForPaymentRequest,
             profile
         )
@@ -147,9 +152,10 @@ class NostrPaymentHandler(
             return
         }
 
-        paymentRequest = request
-        Log.d(TAG, "Created payment request with Nostr: $request")
-        callback.onPaymentRequestReady(request)
+        paymentRequest = request.original
+        paymentRequestBech32 = request.bech32
+        Log.d(TAG, "Created payment request with Nostr: ${request.original}")
+        callback.onPaymentRequestReady(request.original)
 
         // Stop any existing listener
         listener?.stop()

app/src/main/java/com/electricdreams/numo/payment/PaymentMethodHandler.kt

@@ -45,7 +45,7 @@ class PaymentMethodHandler(
         val mintsForPaymentRequest =
             if (mintManager.isSwapFromUnknownMintsEnabled()) null else allowedMints
 
-        val paymentRequest = CashuPaymentHelper.createPaymentRequest(amount, "Payment of $amount sats", mintsForPaymentRequest)
+        val paymentRequest = CashuPaymentHelper.createPaymentRequest(amount, "Payment of $amount sats", mintsForPaymentRequest)?.original
             ?: run {
                 Toast.makeText(activity, R.string.payment_toast_failed_create_request, Toast.LENGTH_SHORT).show()
                 return
@@ -101,9 +101,9 @@ class PaymentMethodHandler(
                     }
                 }
 
-                override fun onNfcReadingStopped() {
+                override fun onNfcReadingStopped(failedInMiddleOfTransaction: Boolean) {
                     activity.runOnUiThread {
-                        onStatusUpdate("NFC reading stopped")
+                        onStatusUpdate(if (failedInMiddleOfTransaction) "NFC reading interrupted" else "NFC reading stopped")
                     }
                 }
             })