fix: exclude client tag from note text search matching

Searching for an app name (e.g. "Amethyst") was returning every event
published through that client, because the local-cache note search
matched the search term against all tag values including the NIP-89
["client", ...] tag. Skip the client tag when matching tag values in
findNotesStartingWith.

https://claude.ai/code/session_01YMs6aXuvs5NaYjzyPH6Zqj

amethyst/src/main/java/com/vitorpamplona/amethyst/model/LocalCache.kt

@@ -252,6 +252,7 @@ import com.vitorpamplona.quartz.nip87Ecash.fedimint.FedimintEvent
 import com.vitorpamplona.quartz.nip87Ecash.recommendation.MintRecommendationEvent
 import com.vitorpamplona.quartz.nip88Polls.poll.PollEvent
 import com.vitorpamplona.quartz.nip88Polls.response.PollResponseEvent
+import com.vitorpamplona.quartz.nip89AppHandlers.clientTag.ClientTag
 import com.vitorpamplona.quartz.nip89AppHandlers.definition.AppDefinitionEvent
 import com.vitorpamplona.quartz.nip89AppHandlers.recommendation.AppRecommendationEvent
 import com.vitorpamplona.quartz.nip90Dvms.contentDiscoveryRequest.NIP90ContentDiscoveryRequestEvent
@@ -2380,6 +2381,13 @@ object LocalCache : ILocalCache, ICacheProvider {
                 note.event is AppSpecificDataEvent
         )
 
+    /**
+     * Tag names whose values should not match text searches. The `client` tag
+     * names the app that published the event, so searching for "Amethyst"
+     * would otherwise return every event posted through Amethyst.
+     */
+    private val excludedTagNamesFromSearch = setOf(ClientTag.TAG_NAME)
+
     fun findNotesStartingWith(
         text: String,
         hiddenUsers: HiddenUsersState,
@@ -2419,7 +2427,7 @@ object LocalCache : ILocalCache, ICacheProvider {
                 return@filter false
             }
 
-            if (note.event?.tags?.tagValueContains(text, true) == true ||
+            if (note.event?.tags?.tagValueContains(text, true, excludedTagNamesFromSearch) == true ||
                 note.idHex.startsWith(text, true)
             ) {
                 return@filter !note.isHiddenFor(hiddenUsers.flow.value)
@@ -2440,7 +2448,7 @@ object LocalCache : ILocalCache, ICacheProvider {
                     return@filter false
                 }
 
-                if (addressable.event?.tags?.tagValueContains(text, true) == true ||
+                if (addressable.event?.tags?.tagValueContains(text, true, excludedTagNamesFromSearch) == true ||
                     addressable.idHex.startsWith(text, true)
                 ) {
                     return@filter !addressable.isHiddenFor(hiddenUsers.flow.value)

quartz/src/commonMain/kotlin/com/vitorpamplona/quartz/nip01Core/core/TagArray.kt

@@ -171,12 +171,14 @@ fun TagArray.isAnyLowercaseTagged(
 ) = this.fastAny { it.size > 1 && it[0] == tagName && it[1].lowercase() in tagValues }
 
 /**
- * Returns `true` if at least one tag has value that contains [text]
+ * Returns `true` if at least one tag has value that contains [text].
+ * Tags whose name is in [exceptNames] are skipped.
  */
 fun TagArray.tagValueContains(
     text: String,
     ignoreCase: Boolean = false,
-) = this.fastAny { it.size > 1 && it[1].contains(text, ignoreCase) }
+    exceptNames: Set<String> = emptySet(),
+) = this.fastAny { it.size > 1 && it[0] !in exceptNames && it[1].contains(text, ignoreCase) }
 
 fun TagArray.containsAllTagNamesWithValues(names: Set<String>): Boolean {
     val remaining = names.toMutableSet()

quartz/src/commonTest/kotlin/com/vitorpamplona/quartz/nip01Core/core/TagArrayTest.kt

@@ -0,0 +1,50 @@
+/*
+ * Copyright (c) 2025 Vitor Pamplona
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy of
+ * this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
+ * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
+ * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.vitorpamplona.quartz.nip01Core.core
+
+import com.vitorpamplona.quartz.nip89AppHandlers.clientTag.ClientTag
+import kotlin.test.Test
+import kotlin.test.assertFalse
+import kotlin.test.assertTrue
+
+class TagArrayTest {
+    private val tags: TagArray =
+        arrayOf(
+            arrayOf("d", "30022"),
+            arrayOf("a", "31990:460c25e682fda7832b52d1f22d3d22b3176d972f60dcdc3212ed8c92ef85065c:1685802317447", "wss://nostr.wine/", "android"),
+            arrayOf("alt", "App recommendations by the author"),
+            arrayOf("client", "Amethyst"),
+        )
+
+    @Test
+    fun matchesTagValues() {
+        assertTrue(tags.tagValueContains("recommendations", ignoreCase = true))
+        assertTrue(tags.tagValueContains("amethyst", ignoreCase = true))
+        assertFalse(tags.tagValueContains("missing", ignoreCase = true))
+    }
+
+    @Test
+    fun skipsExcludedTagNames() {
+        assertFalse(tags.tagValueContains("amethyst", ignoreCase = true, exceptNames = setOf(ClientTag.TAG_NAME)))
+        // other tags still match when the client tag is excluded
+        assertTrue(tags.tagValueContains("recommendations", ignoreCase = true, exceptNames = setOf(ClientTag.TAG_NAME)))
+    }
+}