Limit the text length in the 'in reply to' preview (#4491)

* Limit the text length in the 'in reply to' preview

Otherwise, very long texts with no line breaks can cause a Compose crash

features/messages/impl/src/main/kotlin/io/element/android/features/messages/impl/utils/messagesummary/DefaultMessageSummaryFormatter.kt

@@ -26,6 +26,7 @@ import io.element.android.features.messages.impl.timeline.model.event.TimelineIt
 import io.element.android.features.messages.impl.timeline.model.event.TimelineItemUnknownContent
 import io.element.android.features.messages.impl.timeline.model.event.TimelineItemVideoContent
 import io.element.android.features.messages.impl.timeline.model.event.TimelineItemVoiceContent
+import io.element.android.libraries.core.extensions.toSafeLength
 import io.element.android.libraries.di.ApplicationContext
 import io.element.android.libraries.di.RoomScope
 import io.element.android.libraries.ui.strings.CommonStrings
@@ -35,11 +36,6 @@ import javax.inject.Inject
 class DefaultMessageSummaryFormatter @Inject constructor(
     @ApplicationContext private val context: Context,
 ) : MessageSummaryFormatter {
-    companion object {
-        // Max characters to display in the summary message. This works around https://github.com/element-hq/element-x-android/issues/2105
-        private const val MAX_SAFE_LENGTH = 500
-    }
-
     override fun format(event: TimelineItem.Event): String {
         return when (event.content) {
             is TimelineItemTextBasedContent -> event.content.plainText
@@ -58,6 +54,8 @@ class DefaultMessageSummaryFormatter @Inject constructor(
             is TimelineItemAudioContent -> context.getString(CommonStrings.common_audio)
             is TimelineItemLegacyCallInviteContent -> context.getString(CommonStrings.common_unsupported_call)
             is TimelineItemCallNotifyContent -> context.getString(CommonStrings.common_call_started)
-        }.take(MAX_SAFE_LENGTH)
+        }
+            // Truncate the message to a safe length to avoid crashes in Compose
+            .toSafeLength()
     }
 }

libraries/core/src/main/kotlin/io/element/android/libraries/core/extensions/BasicExtensions.kt

@@ -98,3 +98,22 @@ fun String.ensureEndsLeftToRight() = if (containsRtLOverride()) "$this$LTR_OVERR
 fun String.containsRtLOverride() = contains(RTL_OVERRIDE_CHAR)
 
 fun String.filterDirectionOverrides() = filterNot { it == RTL_OVERRIDE_CHAR || it == LTR_OVERRIDE_CHAR }
+
+/**
+ * This works around https://github.com/element-hq/element-x-android/issues/2105.
+ * @param maxLength Max characters to retrieve. Defaults to `500`.
+ * @param ellipsize Whether to add an ellipsis (`…`) char at the end or not. Defaults to `false`.
+ * @return The string truncated to [maxLength] characters, with an optional ellipsis if larger.
+ */
+fun String.toSafeLength(
+    maxLength: Int = 500,
+    ellipsize: Boolean = false,
+): String {
+    return if (ellipsize) {
+        ellipsize(maxLength)
+    } else if (length > maxLength) {
+        take(maxLength)
+    } else {
+        this
+    }
+}

libraries/matrixui/src/main/kotlin/io/element/android/libraries/matrix/ui/messages/reply/InReplyToView.kt

@@ -31,6 +31,7 @@ import androidx.compose.ui.text.style.TextOverflow
 import androidx.compose.ui.tooling.preview.PreviewParameter
 import androidx.compose.ui.unit.dp
 import io.element.android.compound.theme.ElementTheme
+import io.element.android.libraries.core.extensions.toSafeLength
 import io.element.android.libraries.designsystem.atomic.atoms.PlaceholderAtom
 import io.element.android.libraries.designsystem.icons.CompoundDrawables
 import io.element.android.libraries.designsystem.preview.ElementPreview
@@ -152,8 +153,10 @@ private fun ReplyToContentText(metadata: InReplyToMetadata?) {
     val text = when (metadata) {
         InReplyToMetadata.Redacted -> stringResource(id = CommonStrings.common_message_removed)
         InReplyToMetadata.UnableToDecrypt -> stringResource(id = CommonStrings.common_waiting_for_decryption_key)
-        is InReplyToMetadata.Text -> metadata.text
-        is InReplyToMetadata.Thumbnail -> metadata.text
+        // Add a limit to the text length to avoid a crash in Compose
+        is InReplyToMetadata.Text -> metadata.text.toSafeLength()
+        // Add a limit to the text length to avoid a crash in Compose
+        is InReplyToMetadata.Thumbnail -> metadata.text.toSafeLength()
         null -> ""
     }
     val iconResourceId = when (metadata) {