feat(clink): detect noffer pointers in rich-text as ClinkOfferSegment

Teaches the commons RichTextParser to recognize an inline noffer1...
token and emit a ClinkOfferSegment carrying the decoded NOffer, so a
GUI front end can render a 'Pay' card in the note body (the feed-offer
feature). Bare tokens only for now; nostr:/lightning: prefixed forms
fall through. Covered by ClinkOfferSegmentTest on JVM.

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/richtext/RichTextParser.kt

@@ -23,6 +23,8 @@ package com.vitorpamplona.amethyst.commons.richtext
 import com.vitorpamplona.amethyst.commons.emojicoder.EmojiCoder
 import com.vitorpamplona.amethyst.commons.model.ImmutableListOfLists
 import com.vitorpamplona.amethyst.commons.util.isValidUrl
+import com.vitorpamplona.quartz.experimental.clink.pointers.ClinkPointerParser
+import com.vitorpamplona.quartz.experimental.clink.pointers.NOffer
 import com.vitorpamplona.quartz.experimental.inlineMetadata.Nip54InlineMetadata
 import com.vitorpamplona.quartz.nip30CustomEmoji.CustomEmoji
 import com.vitorpamplona.quartz.nip31Alts.AltTag
@@ -361,6 +363,10 @@ class RichTextParser {
 
         if (word.startsWith("cashuA", true) || word.startsWith("cashuB", true)) return CashuSegment(word)
 
+        if (word.startsWith("noffer1", true)) {
+            (ClinkPointerParser.parse(word) as? NOffer)?.let { return ClinkOfferSegment(word, it) }
+        }
+
         if (word.startsWith('#')) return parseHash(word, tags)
 
         if (EmojiCoder.isCoded(word)) return SecretEmoji(word)

commons/src/commonMain/kotlin/com/vitorpamplona/amethyst/commons/richtext/RichTextParserSegments.kt

@@ -22,6 +22,7 @@ package com.vitorpamplona.amethyst.commons.richtext
 
 import androidx.compose.runtime.Immutable
 import com.vitorpamplona.amethyst.commons.model.ImmutableListOfLists
+import com.vitorpamplona.quartz.experimental.clink.pointers.NOffer
 import kotlinx.collections.immutable.ImmutableList
 import kotlinx.collections.immutable.ImmutableMap
 
@@ -92,6 +93,12 @@ class CashuSegment(
     segment: String,
 ) : Segment(segment)
 
+@Immutable
+class ClinkOfferSegment(
+    segment: String,
+    val offer: NOffer,
+) : Segment(segment)
+
 @Immutable
 class EmailSegment(
     segment: String,

commons/src/commonTest/kotlin/com/vitorpamplona/amethyst/commons/richtext/ClinkOfferSegmentTest.kt

@@ -0,0 +1,62 @@
+/*
+ * 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.amethyst.commons.richtext
+
+import com.vitorpamplona.amethyst.commons.model.EmptyTagList
+import com.vitorpamplona.quartz.experimental.clink.pointers.OfferPriceType
+import kotlin.test.Test
+import kotlin.test.assertEquals
+import kotlin.test.assertTrue
+
+class ClinkOfferSegmentTest {
+    // generated by @shocknet/clink-sdk@1.5.5 (see quartz ClinkInteropTest)
+    private val offerFixed =
+        "noffer1qszqqqzjpqpszqqzpphkven9wgkkjeqprpmhxue69uhhyetvv9ujuumgda3kkmn9wshxgetkqqs8ul5ug253hlh3n75jne0a5xmjur4urfxpzst88cnegg6ds6ka7nsx7zr9c"
+
+    private fun words(text: String) =
+        RichTextParser()
+            .parseText(text, EmptyTagList, null)
+            .paragraphs
+            .flatMap { it.words }
+
+    @Test
+    fun detectsNofferInlineAsClinkOfferSegment() {
+        val segment =
+            words("Pay me here $offerFixed thanks")
+                .filterIsInstance<ClinkOfferSegment>()
+                .single()
+
+        assertEquals(offerFixed, segment.segmentText)
+        assertEquals("offer-id", segment.offer.pointer)
+        assertEquals(OfferPriceType.FIXED, segment.offer.priceType)
+        assertEquals(21000, segment.offer.price)
+    }
+
+    @Test
+    fun malformedNofferIsNotDetected() {
+        assertTrue(words("nope noffer1notvalidbech32 end").none { it is ClinkOfferSegment })
+    }
+
+    @Test
+    fun plainTextHasNoOfferSegment() {
+        assertTrue(words("just a normal sentence").none { it is ClinkOfferSegment })
+    }
+}