From d79b93327412f45e37b97d4fdabd790a564e4d21 Mon Sep 17 00:00:00 2001
From: davotoula <david.kaspar@gmail.com>
Date: Tue, 15 Sep 2026 15:21:39 +0200
Subject: [PATCH] refactor(nwc): validate zapped a/e tags with the existing
 Address and HexKey helpers

---
 .../rpc/NwcTransactionMetadata.kt             | 11 +++--
 .../NwcOutgoingMetadataTest.kt                | 48 ++++++-------------
 2 files changed, 20 insertions(+), 39 deletions(-)

diff --git a/quartz/src/commonMain/kotlin/com/vitorpamplona/quartz/nip47WalletConnect/rpc/NwcTransactionMetadata.kt b/quartz/src/commonMain/kotlin/com/vitorpamplona/quartz/nip47WalletConnect/rpc/NwcTransactionMetadata.kt
index 46770c9698..7d90f3b256 100644
--- a/quartz/src/commonMain/kotlin/com/vitorpamplona/quartz/nip47WalletConnect/rpc/NwcTransactionMetadata.kt
+++ b/quartz/src/commonMain/kotlin/com/vitorpamplona/quartz/nip47WalletConnect/rpc/NwcTransactionMetadata.kt
@@ -20,10 +20,11 @@
  */
 package com.vitorpamplona.quartz.nip47WalletConnect.rpc
 
+import com.vitorpamplona.quartz.nip01Core.core.Address
 import com.vitorpamplona.quartz.nip01Core.core.Event
 import com.vitorpamplona.quartz.nip01Core.core.RawJson
+import com.vitorpamplona.quartz.nip01Core.core.isValid
 import com.vitorpamplona.quartz.nip19Bech32.decodePublicKeyAsHexOrNull
-import com.vitorpamplona.quartz.utils.Hex
 
 class NwcTransactionMetadata(
     val comment: String?,
@@ -45,8 +46,8 @@ class NwcTransactionMetadata(
         val pubkeyHex: String?,
         val recipientPubkeyHex: String?,
         val content: String?,
-        val zappedEventId: String? = null,
-        val zappedAddress: String? = null,
+        val zappedEventId: String?,
+        val zappedAddress: String?,
     )
 
     fun senderPubkeyHex(): String? = nostr?.pubkeyHex ?: payerData?.pubkey?.let { decodePublicKeyAsHexOrNull(it) }
@@ -109,8 +110,8 @@ class NwcTransactionMetadata(
                         val value = tagList[1] as? String ?: return@forEach
                         when (tagList[0]) {
                             "p" -> if (recipientHex == null) recipientHex = value
-                            "e" -> if (zappedEventId == null && value.length == 64 && Hex.isHex64(value)) zappedEventId = value
-                            "a" -> if (zappedAddress == null) zappedAddress = value
+                            "e" -> if (zappedEventId == null && value.isValid()) zappedEventId = value
+                            "a" -> if (zappedAddress == null) zappedAddress = Address.parse(value)?.toValue()
                         }
                     }
 
diff --git a/quartz/src/commonTest/kotlin/com/vitorpamplona/quartz/nip47WalletConnect/NwcOutgoingMetadataTest.kt b/quartz/src/commonTest/kotlin/com/vitorpamplona/quartz/nip47WalletConnect/NwcOutgoingMetadataTest.kt
index 5b26d05454..8bddfc1446 100644
--- a/quartz/src/commonTest/kotlin/com/vitorpamplona/quartz/nip47WalletConnect/NwcOutgoingMetadataTest.kt
+++ b/quartz/src/commonTest/kotlin/com/vitorpamplona/quartz/nip47WalletConnect/NwcOutgoingMetadataTest.kt
@@ -254,23 +254,16 @@ class NwcOutgoingMetadataTest {
         assertEquals(recipientHex, parsed.recipientPubkeyHex(), "the p tag is still read with the e tag in front of it")
     }
 
+    private fun parseTags(vararg tags: List<String>) = assertNotNull(NwcTransactionMetadata.parse(mapOf("nostr" to mapOf("tags" to tags.toList()))))
+
     @Test
     fun aProfileZapHasNoNote() {
-        val parsed =
-            assertNotNull(
-                NwcTransactionMetadata.parse(mapOf("nostr" to mapOf("tags" to listOf(listOf("p", recipientHex))))),
-            )
-        assertNull(parsed.zappedNoteId())
+        assertNull(parseTags(listOf("p", recipientHex)).zappedNoteId())
     }
 
     @Test
     fun tagOrderDoesNotMatter() {
-        val parsed =
-            assertNotNull(
-                NwcTransactionMetadata.parse(
-                    mapOf("nostr" to mapOf("tags" to listOf(listOf("e", noteHex), listOf("p", recipientHex)))),
-                ),
-            )
+        val parsed = parseTags(listOf("e", noteHex), listOf("p", recipientHex))
         assertEquals(recipientHex, parsed.recipientPubkeyHex())
         assertEquals(noteHex, parsed.zappedNoteId())
     }
@@ -278,33 +271,20 @@ class NwcOutgoingMetadataTest {
     @Test
     fun anAddressableZapPrefersTheAddress() {
         val address = "30023:$recipientHex:my-article"
-        val parsed =
-            assertNotNull(
-                NwcTransactionMetadata.parse(
-                    mapOf("nostr" to mapOf("tags" to listOf(listOf("e", noteHex), listOf("a", address), listOf("p", recipientHex)))),
-                ),
-            )
-        assertEquals(address, parsed.zappedNoteId())
+        assertEquals(address, parseTags(listOf("e", noteHex), listOf("a", address), listOf("p", recipientHex)).zappedNoteId())
+    }
+
+    @Test
+    fun aMalformedAddressFallsBackToTheEventId() {
+        assertEquals(noteHex, parseTags(listOf("e", noteHex), listOf("a", "not-an-address"), listOf("p", recipientHex)).zappedNoteId())
     }
 
     @Test
     fun aMalformedEventIdIsIgnored() {
-        val parsed =
-            assertNotNull(
-                NwcTransactionMetadata.parse(
-                    mapOf("nostr" to mapOf("tags" to listOf(listOf("e", "not-a-note"), listOf("p", recipientHex)))),
-                ),
-            )
-        assertNull(parsed.zappedNoteId())
-
-        // isHex64 checks only the first 64 chars; a longer id must not slip through.
-        val tooLong =
-            assertNotNull(
-                NwcTransactionMetadata.parse(
-                    mapOf("nostr" to mapOf("tags" to listOf(listOf("e", noteHex + "ff"), listOf("p", recipientHex)))),
-                ),
-            )
-        assertNull(tooLong.zappedNoteId())
+        // "noteHex + ff": the id check must bound the length, not just scan 64 hex chars.
+        listOf("not-a-note", noteHex + "ff").forEach { bad ->
+            assertNull(parseTags(listOf("e", bad), listOf("p", recipientHex)).zappedNoteId(), bad)
+        }
     }
 
     @Test