Fix crash when saving empty formatted text drafts.

app/src/main/java/org/thoughtcrime/securesms/conversation/ConversationParentFragment.java

@@ -3830,7 +3830,7 @@ public class ConversationParentFragment extends Fragment
 
     @Override
     public void onTextChanged(@NonNull CharSequence text) {
-      handleSaveDraftOnTextChange(text);
+      handleSaveDraftOnTextChange(composeText.getTextTrimmed());
       handleTypingIndicatorOnTextChange(text.toString());
     }
 

app/src/main/java/org/thoughtcrime/securesms/conversation/MessageStyler.kt

@@ -84,7 +84,7 @@ object MessageStyler {
   fun hasStyling(text: Spanned): Boolean {
     return if (FeatureFlags.textFormatting()) {
       text.getSpans(0, text.length, CharacterStyle::class.java)
-        .any { s -> isSupportedCharacterStyle(s) }
+        .any { s -> isSupportedCharacterStyle(s) && text.getSpanEnd(s) - text.getSpanStart(s) > 0 }
     } else {
       false
     }
@@ -96,7 +96,7 @@ object MessageStyler {
       text
         .getSpans(0, text.length, CharacterStyle::class.java)
         .filter { s -> isSupportedCharacterStyle(s) }
-        .map { span: CharacterStyle ->
+        .mapNotNull { span: CharacterStyle ->
           val spanStart = text.getSpanStart(span)
           val spanLength = text.getSpanEnd(span) - spanStart
 
@@ -107,7 +107,11 @@ object MessageStyler {
             else -> throw IllegalArgumentException("Provided text contains unsupported spans")
           }
 
-          BodyRangeList.BodyRange.newBuilder().setStart(spanStart).setLength(spanLength).setStyle(style).build()
+          if (spanLength > 0) {
+            BodyRangeList.BodyRange.newBuilder().setStart(spanStart).setLength(spanLength).setStyle(style).build()
+          } else {
+            null
+          }
         }
         .toList()
     } else {

app/src/main/java/org/thoughtcrime/securesms/conversation/drafts/DraftRepository.kt

@@ -61,14 +61,15 @@ class DraftRepository(
   fun loadDrafts(threadId: Long): Single<DatabaseDraft> {
     return Single.fromCallable {
       val drafts: Drafts = draftTable.getDrafts(threadId)
-      val bodyRangesDraft = drafts.getDraftOfType(DraftTable.Draft.BODY_RANGES)
+      val bodyRangesDraft: DraftTable.Draft? = drafts.getDraftOfType(DraftTable.Draft.BODY_RANGES)
+      val textDraft: DraftTable.Draft? = drafts.getDraftOfType(DraftTable.Draft.TEXT)
       var updatedText: Spannable? = null
 
-      if (bodyRangesDraft != null) {
+      if (textDraft != null && bodyRangesDraft != null) {
         val bodyRanges: BodyRangeList = BodyRangeList.parseFrom(Base64.decodeOrThrow(bodyRangesDraft.value))
         val mentions: List<Mention> = MentionUtil.bodyRangeListToMentions(bodyRanges)
 
-        val updated = MentionUtil.updateBodyAndMentionsWithDisplayNames(context, drafts.getDraftOfType(DraftTable.Draft.TEXT)!!.value, mentions)
+        val updated = MentionUtil.updateBodyAndMentionsWithDisplayNames(context, textDraft.value, mentions)
 
         updatedText = SpannableString(updated.body)
         MentionAnnotation.setMentionAnnotations(updatedText, updated.mentions)