Refactor and cleanup backupv2 media restore.

app/src/main/java/org/thoughtcrime/securesms/backup/v2/BackupRestoreManager.kt

@@ -30,6 +30,7 @@ object BackupRestoreManager {
     SignalExecutors.BOUNDED.execute {
       synchronized(this) {
         val restoringAttachments = messageRecords
+          .asSequence()
           .mapNotNull { (it as? MmsMessageRecord?)?.slideDeck?.slides }
           .flatten()
           .mapNotNull { it.asAttachment() as? DatabaseAttachment }
@@ -41,10 +42,11 @@ object BackupRestoreManager {
           .toSet()
 
         reprioritizedAttachments += restoringAttachments.map { it.first }
-        val thumbnailJobs = restoringAttachments.map {
-          val (attachmentId, mmsId) = it
+
+        val thumbnailJobs = restoringAttachments.map { (attachmentId, mmsId) ->
           RestoreAttachmentThumbnailJob(attachmentId = attachmentId, messageId = mmsId, highPriority = true)
         }
+
         if (thumbnailJobs.isNotEmpty()) {
           AppDependencies.jobManager.addAll(thumbnailJobs)
         }

app/src/main/java/org/thoughtcrime/securesms/backup/v2/database/DatabaseAttachmentBackupExtensions.kt

@@ -0,0 +1,129 @@
+/*
+ * Copyright 2024 Signal Messenger, LLC
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+package org.thoughtcrime.securesms.backup.v2.database
+
+import android.text.TextUtils
+import org.signal.core.util.Base64
+import org.thoughtcrime.securesms.attachments.DatabaseAttachment
+import org.thoughtcrime.securesms.attachments.InvalidAttachmentException
+import org.thoughtcrime.securesms.backup.v2.BackupRepository
+import org.thoughtcrime.securesms.backup.v2.BackupRepository.getThumbnailMediaName
+import org.thoughtcrime.securesms.keyvalue.SignalStore
+import org.thoughtcrime.securesms.util.Util
+import org.whispersystems.signalservice.api.backup.MediaName
+import org.whispersystems.signalservice.api.messages.SignalServiceAttachmentPointer
+import org.whispersystems.signalservice.api.messages.SignalServiceAttachmentRemoteId
+import java.io.IOException
+import java.util.Optional
+
+/**
+ * Creates a [SignalServiceAttachmentPointer] for the archived attachment of the given [DatabaseAttachment].
+ */
+@Throws(InvalidAttachmentException::class)
+fun DatabaseAttachment.createArchiveAttachmentPointer(useArchiveCdn: Boolean): SignalServiceAttachmentPointer {
+  if (remoteKey.isNullOrBlank()) {
+    throw InvalidAttachmentException("empty encrypted key")
+  }
+
+  if (remoteDigest == null) {
+    throw InvalidAttachmentException("no digest")
+  }
+
+  return try {
+    val (remoteId, cdnNumber) = if (useArchiveCdn) {
+      val backupKey = SignalStore.svr.getOrCreateMasterKey().deriveBackupKey()
+      val backupDirectories = BackupRepository.getCdnBackupDirectories().successOrThrow()
+
+      val id = SignalServiceAttachmentRemoteId.Backup(
+        backupDir = backupDirectories.backupDir,
+        mediaDir = backupDirectories.mediaDir,
+        mediaId = backupKey.deriveMediaId(MediaName(archiveMediaName!!)).encode()
+      )
+
+      id to archiveCdn
+    } else {
+      if (remoteLocation.isNullOrEmpty()) {
+        throw InvalidAttachmentException("empty content id")
+      }
+
+      SignalServiceAttachmentRemoteId.from(remoteLocation) to cdn.cdnNumber
+    }
+
+    val key = Base64.decode(remoteKey)
+
+    SignalServiceAttachmentPointer(
+      cdnNumber = cdnNumber,
+      remoteId = remoteId,
+      contentType = null,
+      key = key,
+      size = Optional.of(Util.toIntExact(size)),
+      preview = Optional.empty(),
+      width = 0,
+      height = 0,
+      digest = Optional.ofNullable(remoteDigest),
+      incrementalDigest = Optional.ofNullable(getIncrementalDigest()),
+      incrementalMacChunkSize = incrementalMacChunkSize,
+      fileName = Optional.ofNullable(fileName),
+      voiceNote = voiceNote,
+      isBorderless = borderless,
+      isGif = videoGif,
+      caption = Optional.empty(),
+      blurHash = Optional.ofNullable(blurHash).map { it.hash },
+      uploadTimestamp = uploadTimestamp,
+      uuid = uuid
+    )
+  } catch (e: IOException) {
+    throw InvalidAttachmentException(e)
+  } catch (e: ArithmeticException) {
+    throw InvalidAttachmentException(e)
+  }
+}
+
+/**
+ * Creates a [SignalServiceAttachmentPointer] for an archived thumbnail of the given [DatabaseAttachment].
+ */
+@Throws(InvalidAttachmentException::class)
+fun DatabaseAttachment.createArchiveThumbnailPointer(): SignalServiceAttachmentPointer {
+  if (TextUtils.isEmpty(remoteKey)) {
+    throw InvalidAttachmentException("empty encrypted key")
+  }
+
+  val backupKey = SignalStore.svr.getOrCreateMasterKey().deriveBackupKey()
+  val backupDirectories = BackupRepository.getCdnBackupDirectories().successOrThrow()
+  return try {
+    val key = backupKey.deriveThumbnailTransitKey(getThumbnailMediaName())
+    val mediaId = backupKey.deriveMediaId(getThumbnailMediaName()).encode()
+    SignalServiceAttachmentPointer(
+      cdnNumber = archiveCdn,
+      remoteId = SignalServiceAttachmentRemoteId.Backup(
+        backupDir = backupDirectories.backupDir,
+        mediaDir = backupDirectories.mediaDir,
+        mediaId = mediaId
+      ),
+      contentType = null,
+      key = key,
+      size = Optional.empty(),
+      preview = Optional.empty(),
+      width = 0,
+      height = 0,
+      digest = Optional.empty(),
+      incrementalDigest = Optional.empty(),
+      incrementalMacChunkSize = incrementalMacChunkSize,
+      fileName = Optional.empty(),
+      voiceNote = voiceNote,
+      isBorderless = borderless,
+      isGif = videoGif,
+      caption = Optional.empty(),
+      blurHash = Optional.ofNullable(blurHash).map { it.hash },
+      uploadTimestamp = uploadTimestamp,
+      uuid = uuid
+    )
+  } catch (e: IOException) {
+    throw InvalidAttachmentException(e)
+  } catch (e: ArithmeticException) {
+    throw InvalidAttachmentException(e)
+  }
+}