Add UI components for Release Channel.

app/src/main/java/org/thoughtcrime/securesms/releasechannel/ReleaseChannel.kt

@@ -0,0 +1,69 @@
+package org.thoughtcrime.securesms.releasechannel
+
+import org.thoughtcrime.securesms.attachments.PointerAttachment
+import org.thoughtcrime.securesms.database.MessageDatabase
+import org.thoughtcrime.securesms.database.SignalDatabase
+import org.thoughtcrime.securesms.database.model.databaseprotos.BodyRangeList
+import org.thoughtcrime.securesms.mms.IncomingMediaMessage
+import org.thoughtcrime.securesms.recipients.RecipientId
+import org.whispersystems.libsignal.util.guava.Optional
+import org.whispersystems.signalservice.api.messages.SignalServiceAttachment
+import org.whispersystems.signalservice.api.messages.SignalServiceAttachmentPointer
+import org.whispersystems.signalservice.api.messages.SignalServiceAttachmentRemoteId
+import java.util.UUID
+
+/**
+ * One stop shop for inserting Release Channel messages.
+ */
+object ReleaseChannel {
+
+  const val CDN_NUMBER = -1
+
+  fun insertAnnouncement(
+    recipientId: RecipientId,
+    body: String,
+    threadId: Long,
+    image: String? = null,
+    serverUuid: String? = UUID.randomUUID().toString(),
+    messageRanges: BodyRangeList? = null
+  ): MessageDatabase.InsertResult? {
+
+    val attachments: Optional<List<SignalServiceAttachment>> = if (image != null) {
+      val attachment = SignalServiceAttachmentPointer(
+        CDN_NUMBER,
+        SignalServiceAttachmentRemoteId.from(""),
+        "image/webp",
+        null,
+        Optional.absent(),
+        Optional.absent(),
+        0,
+        0,
+        Optional.absent(),
+        Optional.of(image),
+        false,
+        false,
+        false,
+        Optional.absent(),
+        Optional.absent(),
+        System.currentTimeMillis()
+      )
+
+      Optional.of(listOf(attachment))
+    } else {
+      Optional.absent()
+    }
+
+    val message = IncomingMediaMessage(
+      from = recipientId,
+      sentTimeMillis = System.currentTimeMillis(),
+      serverTimeMillis = System.currentTimeMillis(),
+      receivedTimeMillis = System.currentTimeMillis(),
+      body = body,
+      attachments = PointerAttachment.forPointers(attachments),
+      serverGuid = serverUuid,
+      messageRanges = messageRanges
+    )
+
+    return SignalDatabase.mms.insertSecureDecryptedMessageInbox(message, threadId).orNull()
+  }
+}