Merge pull request #230 from maxmoney21m/bugfix/223-invoice-intent

Fix LN invoice in expandable text component

app/src/main/java/com/vitorpamplona/amethyst/service/lnurl/LnInvoiceUtil.kt

@@ -152,4 +152,22 @@ object LnInvoiceUtil {
             null
         }
     }
+
+    /**
+     * If the string contains an LN invoice, returns a Pair of the start and end
+     * positions of the invoice in the string. Otherwise, returns (0, 0). This is
+     * used to ensure we don't accidentally cut an invoice in the middle when taking
+     * only a portion of the available text.
+     */
+    fun locateInvoice(input: String?): Pair<Int, Int> {
+        if (input == null) {
+            return Pair(0, 0)
+        }
+        val matcher = invoicePattern.matcher(input)
+        return if (matcher.find()) {
+            Pair(matcher.start(), matcher.end())
+        } else {
+            Pair(0, 0)
+        }
+    }
 }

app/src/main/java/com/vitorpamplona/amethyst/ui/components/ExpandableRichTextViewer.kt

@@ -26,8 +26,11 @@ import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.unit.dp
 import androidx.navigation.NavController
 import com.vitorpamplona.amethyst.R
+import com.vitorpamplona.amethyst.service.lnurl.LnInvoiceUtil
 import com.vitorpamplona.amethyst.ui.screen.loggedIn.AccountViewModel
 
+const val SHORT_TEXT_LENGTH = 350
+
 @Composable
 fun ExpandableRichTextViewer(
     content: String,
@@ -40,7 +43,16 @@ fun ExpandableRichTextViewer(
 ) {
     var showFullText by remember { mutableStateOf(false) }
 
-    val text = if (showFullText) content else content.take(350)
+    val text = if (showFullText) {
+        content
+    } else {
+        val (lnStart, lnEnd) = LnInvoiceUtil.locateInvoice(content)
+        if (lnStart < SHORT_TEXT_LENGTH && lnEnd > 0) {
+            content.take(lnEnd)
+        } else {
+            content.take(SHORT_TEXT_LENGTH)
+        }
+    }
 
     Box(contentAlignment = Alignment.BottomCenter) {
         // CompositionLocalProvider(LocalLayoutDirection provides LayoutDirection.Rtl) {