Fix large message size calculation to use bytes.

Author: greyson-signal

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

@@ -1052,8 +1052,10 @@ private void setBodyText(@NonNull MessageRecord messageRecord,
 
       if (hasExtraText(messageRecord)) {
         bodyText.setOverflowText(getLongMessageSpan(messageRecord));
+        bodyText.setMaxLength(messageRecord.getBody().length() - 2);
       } else {
         bodyText.setOverflowText(null);
+        bodyText.setMaxLength(messageRecord.getBody().length());
       }
 
       if (messageRecord.isOutgoing()) {

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

@@ -2,14 +2,10 @@ package org.thoughtcrime.securesms.conversation
 
 import android.content.Context
 import android.os.Parcelable
-import androidx.annotation.ColorRes
 import androidx.annotation.DrawableRes
 import androidx.annotation.StringRes
 import kotlinx.parcelize.Parcelize
 import org.thoughtcrime.securesms.R
-import org.thoughtcrime.securesms.util.CharacterCalculator
-import org.thoughtcrime.securesms.util.PushCharacterCalculator
-import java.lang.IllegalArgumentException
 
 /**
  * The kinds of messages you can send, e.g. a plain Signal message, an SMS message, etc.
@@ -22,22 +18,14 @@ sealed class MessageSendType(
   val composeHintRes: Int,
   @DrawableRes
   val buttonDrawableRes: Int,
-  @DrawableRes
-  val menuDrawableRes: Int,
-  @ColorRes
-  val backgroundColorRes: Int,
   val transportType: TransportType,
-  val characterCalculator: CharacterCalculator
+  val maxBodyByteSize: Int
 ) : Parcelable {
 
   @get:JvmName("usesSignalTransport")
   val usesSignalTransport
     get() = transportType == TransportType.SIGNAL
 
-  fun calculateCharacters(body: String): CharacterCalculator.CharacterState {
-    return characterCalculator.calculateCharacters(body)
-  }
-
   open fun getTitle(context: Context): String {
     return context.getString(titleRes)
   }
@@ -50,26 +38,12 @@ sealed class MessageSendType(
     titleRes = R.string.ConversationActivity_send_message_content_description,
     composeHintRes = R.string.conversation_activity__type_message_push,
     buttonDrawableRes = R.drawable.ic_send_lock_24,
-    menuDrawableRes = R.drawable.ic_secure_24,
-    backgroundColorRes = R.color.core_ultramarine,
     transportType = TransportType.SIGNAL,
-    characterCalculator = PushCharacterCalculator()
+    maxBodyByteSize = 2048
   )
 
   enum class TransportType {
     SIGNAL,
     SMS
   }
-
-  companion object {
-    @JvmStatic
-    fun getAllAvailable(): List<MessageSendType> {
-      return listOf(SignalMessageSendType)
-    }
-
-    @JvmStatic
-    fun getFirstForTransport(transportType: TransportType): MessageSendType {
-      return getAllAvailable().firstOrNull { it.transportType == transportType } ?: throw IllegalArgumentException("No options available for desired type $transportType!")
-    }
-  }
 }

app/src/main/java/org/thoughtcrime/securesms/conversation/v2/ConversationFragment.kt

@@ -1281,25 +1281,6 @@ class ConversationFragment :
     }
   }
 
-  private fun calculateCharactersRemaining() {
-    val messageBody: String = binding.conversationInputPanel.embeddedTextEditor.textTrimmed.toString()
-    val charactersLeftView: TextView = binding.conversationInputSpaceLeft
-    val characterState = MessageSendType.SignalMessageSendType.calculateCharacters(messageBody)
-
-    if (characterState.charactersRemaining <= 15 || characterState.messagesSpent > 1) {
-      charactersLeftView.text = String.format(
-        Locale.getDefault(),
-        "%d/%d (%d)",
-        characterState.charactersRemaining,
-        characterState.maxTotalMessageSize,
-        characterState.messagesSpent
-      )
-      charactersLeftView.visibility = View.VISIBLE
-    } else {
-      charactersLeftView.visibility = View.GONE
-    }
-  }
-
   private fun registerForResults() {
     addToContactsLauncher = registerForActivityResult(AddToContactsContract()) {}
     conversationActivityResultContracts = ConversationActivityResultContracts(this, ActivityResultCallbacks())
@@ -4020,7 +4001,6 @@ class ConversationFragment :
     }
 
     override fun afterTextChanged(s: Editable) {
-      calculateCharactersRemaining()
       if (composeText.textTrimmed.isEmpty() || beforeLength == 0) {
         composeText.postDelayed({
           if (lifecycle.currentState.isAtLeast(Lifecycle.State.CREATED)) {

app/src/main/java/org/thoughtcrime/securesms/conversation/v2/ConversationRepository.kt

@@ -40,7 +40,6 @@ import org.thoughtcrime.securesms.components.emoji.EmojiStrings
 import org.thoughtcrime.securesms.contactshare.Contact
 import org.thoughtcrime.securesms.contactshare.ContactUtil
 import org.thoughtcrime.securesms.conversation.ConversationMessage
-import org.thoughtcrime.securesms.conversation.MessageSendType
 import org.thoughtcrime.securesms.conversation.mutiselect.MultiselectPart
 import org.thoughtcrime.securesms.conversation.v2.RequestReviewState.GroupReviewState
 import org.thoughtcrime.securesms.conversation.v2.RequestReviewState.IndividualReviewState
@@ -186,8 +185,7 @@ class ConversationRepository(
     val sendCompletable = Completable.create { emitter ->
       val splitMessage: MessageUtil.SplitResult = MessageUtil.getSplitMessage(
         applicationContext,
-        body,
-        MessageSendType.SignalMessageSendType.calculateCharacters(body).maxPrimaryMessageSize
+        body
       )
 
       val outgoingMessageSlideDeck: SlideDeck? = splitMessage.textSlide.map {

app/src/main/java/org/thoughtcrime/securesms/mediasend/v2/MediaSelectionRepository.kt

@@ -169,7 +169,7 @@ class MediaSelectionRepository(context: Context) {
           )
         )
       } else {
-        val splitMessage = MessageUtil.getSplitMessage(context, trimmedBody, sendType.calculateCharacters(trimmedBody).maxPrimaryMessageSize)
+        val splitMessage = MessageUtil.getSplitMessage(context, trimmedBody)
         val splitBody = splitMessage.body
 
         if (splitMessage.textSlide.isPresent) {
@@ -325,7 +325,7 @@ class MediaSelectionRepository(context: Context) {
         Log.w(TAG, "Asked to send an unexpected mimeType: '" + mediaItem.contentType + "'. Skipping.")
       }
     }
-    val splitMessage = MessageUtil.getSplitMessage(context, body, sendType.calculateCharacters(body).maxPrimaryMessageSize)
+    val splitMessage = MessageUtil.getSplitMessage(context, body)
     val splitBody = splitMessage.body
     if (splitMessage.textSlide.isPresent) {
       slideDeck.addSlide(splitMessage.textSlide.get())

app/src/main/java/org/thoughtcrime/securesms/sharing/MultiShareSender.java

@@ -51,6 +51,7 @@
 import org.thoughtcrime.securesms.util.MessageUtil;
 import org.thoughtcrime.securesms.util.Util;
 
+import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
@@ -62,6 +63,8 @@
 import java.util.concurrent.TimeUnit;
 import java.util.stream.Collectors;
 
+import okio.Utf8;
+
 /**
  * MultiShareSender encapsulates send logic (stolen from {@link org.thoughtcrime.securesms.conversation.ConversationActivity}
  * and provides a means to:
@@ -113,8 +116,7 @@ public static MultiShareSendResultCollection sendSync(@NonNull MultiShareArgs mu
       List<Contact>   contacts           = multiShareArgs.getSharedContacts();
       SlideDeck       slideDeck          = new SlideDeck(primarySlideDeck);
 
-      boolean needsSplit = message != null &&
-                           message.length() > sendType.calculateCharacters(message).maxPrimaryMessageSize;
+      boolean needsSplit = message != null && Utf8.size(message) > MessageUtil.MAX_MESSAGE_SIZE_BYTES;
       boolean hasMmsMedia = !multiShareArgs.getMedia().isEmpty() ||
                             (multiShareArgs.getDataUri() != null && multiShareArgs.getDataUri() != Uri.EMPTY) ||
                             multiShareArgs.getStickerLocator() != null ||
@@ -196,7 +198,7 @@ private static void sendMediaMessageOrCollectStoryToBatch(@NonNull Context conte
   {
     String body = multiShareArgs.getDraftText();
     if (sendType.usesSignalTransport() && body != null) {
-      MessageUtil.SplitResult splitMessage = MessageUtil.getSplitMessage(context, body, sendType.calculateCharacters(body).maxPrimaryMessageSize);
+      MessageUtil.SplitResult splitMessage = MessageUtil.getSplitMessage(context, body);
       body = splitMessage.getBody();
 
       if (splitMessage.getTextSlide().isPresent()) {

app/src/main/java/org/thoughtcrime/securesms/util/MessageUtil.java

@@ -0,0 +1,45 @@
+package org.thoughtcrime.securesms.util
+
+import android.content.Context
+import org.signal.core.util.splitByByteLength
+import org.thoughtcrime.securesms.mms.TextSlide
+import org.thoughtcrime.securesms.providers.BlobProvider
+import java.text.SimpleDateFormat
+import java.util.Date
+import java.util.Locale
+import java.util.Optional
+
+object MessageUtil {
+  const val MAX_MESSAGE_SIZE_BYTES: Int = 2000 // Technically 2048, but we'll play it a little safe
+
+  /**
+   * @return If the message is longer than the allowed text size, this will return trimmed text with
+   * an accompanying TextSlide. Otherwise it'll just return the original text.
+   */
+  @JvmStatic
+  fun getSplitMessage(context: Context, rawText: String): SplitResult {
+    val (trimmed, remainder) = rawText.splitByByteLength(MAX_MESSAGE_SIZE_BYTES)
+
+    return if (remainder != null) {
+      val textData = rawText.toByteArray()
+      val timestamp = SimpleDateFormat("yyyy-MM-dd-HHmmss", Locale.US).format(Date())
+      val filename = String.format("signal-%s.txt", timestamp)
+      val textUri = BlobProvider.getInstance()
+        .forData(textData)
+        .withMimeType(MediaUtil.LONG_TEXT)
+        .withFileName(filename)
+        .createForSingleSessionInMemory()
+
+      val textSlide = Optional.of(TextSlide(context, textUri, filename, textData.size.toLong()))
+
+      SplitResult(trimmed, textSlide)
+    } else {
+      SplitResult(trimmed, Optional.empty())
+    }
+  }
+
+  data class SplitResult(
+    val body: String,
+    val textSlide: Optional<TextSlide>
+  )
+}

app/src/main/java/org/thoughtcrime/securesms/util/MessageUtil.kt

@@ -5,11 +5,17 @@
 
 package org.signal.core.util
 
+import okio.utf8Size
+import org.signal.core.util.logging.Log
 import java.net.URLEncoder
+import java.nio.ByteBuffer
+import java.nio.CharBuffer
 import java.nio.charset.StandardCharsets
 import kotlin.contracts.ExperimentalContracts
 import kotlin.contracts.contract
 
+private const val TAG: String = "StringExtensions"
+
 /**
  * Treats the string as a serialized list of tokens and tells you if an item is present in the list.
  * In addition to exact matches, this handles wildcards at the end of an item.
@@ -79,3 +85,37 @@ fun CharSequence?.isNotNullOrBlank(): Boolean {
 fun String.urlEncode(): String {
   return URLEncoder.encode(this, StandardCharsets.UTF_8.name())
 }
+
+/**
+ * Splits a string into two parts, such that the first part will be at most [byteLength] bytes long.
+
+ * The first item of the pair will be the shortened string, and the second item will be the remainder.
+ * Appending the two parts together will give you back the original string.
+ *
+ * If the input string is already less than [byteLength] bytes, the second item will be null.
+ */
+fun String.splitByByteLength(byteLength: Int): Pair<String, String?> {
+  if (this.utf8Size() <= byteLength) {
+    return this to null
+  }
+
+  val charBuffer = CharBuffer.wrap(this)
+  val encoder = Charsets.UTF_8.newEncoder()
+  val outputBuffer = ByteBuffer.allocate(byteLength)
+
+  encoder.encode(charBuffer, outputBuffer, true)
+  charBuffer.flip()
+
+  var firstPart = charBuffer.toString()
+
+  // Unfortunately some Android implementations will cause the charBuffer to go a step beyond what it should.
+  // It's always extremely close (in testing, only ever off by 1), but as a workaround, we chop off characters
+  // at the end until it fits. Bummer.
+  while (firstPart.utf8Size() > byteLength) {
+    Log.w(TAG, "Had to chop off a character to make it fit under the byte limit.")
+    firstPart = firstPart.substring(0, firstPart.length - 1)
+  }
+
+  val remainder = this.substring(firstPart.length)
+  return firstPart to remainder
+}