Allow envelopes to be decrypted but not decoded (#137)

* add matching decryption code to swift

* fix up the lint issues

* fix up the tests

library/src/androidTest/java/org/xmtp/android/library/MessageTest.kt

@@ -94,7 +94,9 @@ class MessageTest {
             keyMaterial = invitationv1.aes256GcmHkdfSha256.keyMaterial.toByteArray()
         )
         val decoded = MessageV2Builder.buildDecode(
-            message1,
+            id = "",
+            client = client,
+            message = message1,
             keyMaterial = invitationv1.aes256GcmHkdfSha256.keyMaterial.toByteArray(),
             topic = invitationv1.topic
         )

library/src/main/java/org/xmtp/android/library/Conversation.kt

@@ -10,6 +10,7 @@ import org.xmtp.proto.keystore.api.v1.Keystore.TopicMap.TopicData
 import org.xmtp.proto.message.api.v1.MessageApiOuterClass
 import org.xmtp.proto.message.contents.Invitation
 import org.xmtp.proto.message.contents.Invitation.InvitationV1.Aes256gcmHkdfsha256
+import uniffi.xmtp_dh.org.xmtp.android.library.messages.DecryptedMessage
 import java.util.Date
 
 sealed class Conversation {
@@ -180,6 +181,18 @@ sealed class Conversation {
         }
     }
 
+    fun decryptedMessages(
+        limit: Int? = null,
+        before: Date? = null,
+        after: Date? = null,
+        direction: PagingInfoSortDirection = MessageApiOuterClass.SortDirection.SORT_DIRECTION_DESCENDING,
+    ): List<DecryptedMessage> {
+        return when (this) {
+            is V1 -> conversationV1.decryptedMessages(limit, before, after, direction)
+            is V2 -> conversationV2.decryptedMessages(limit, before, after, direction)
+        }
+    }
+
     val client: Client
         get() {
             return when (this) {

library/src/main/java/org/xmtp/android/library/ConversationV1.kt

@@ -22,6 +22,7 @@ import org.xmtp.android.library.messages.sentAt
 import org.xmtp.android.library.messages.toPublicKeyBundle
 import org.xmtp.android.library.messages.walletAddress
 import org.xmtp.proto.message.api.v1.MessageApiOuterClass
+import uniffi.xmtp_dh.org.xmtp.android.library.messages.DecryptedMessage
 import java.util.Date
 
 data class ConversationV1(
@@ -56,21 +57,59 @@ data class ConversationV1(
         }
     }
 
-    fun decode(envelope: Envelope): DecodedMessage {
-        val message = Message.parseFrom(envelope.message)
-        val decrypted = message.v1.decrypt(client.privateKeyBundleV1)
-        val encodedMessage = EncodedContent.parseFrom(decrypted)
-        val header = message.v1.header
-        val decoded = DecodedMessage(
-            topic = envelope.contentTopic,
-            encodedContent = encodedMessage,
-            senderAddress = header.sender.walletAddress,
-            sent = message.v1.sentAt
-        )
+    fun decryptedMessages(
+        limit: Int? = null,
+        before: Date? = null,
+        after: Date? = null,
+        direction: PagingInfoSortDirection = MessageApiOuterClass.SortDirection.SORT_DIRECTION_DESCENDING,
+    ): List<DecryptedMessage> {
+        val pagination =
+            Pagination(limit = limit, before = before, after = after, direction = direction)
+
+        val envelopes = runBlocking {
+            client.apiClient.envelopes(
+                topic = Topic.directMessageV1(client.address, peerAddress).description,
+                pagination = pagination
+            )
+        }
 
-        decoded.id = generateId(envelope)
+        return envelopes.map { decrypt(it) }
+    }
 
-        return decoded
+    fun decrypt(envelope: Envelope): DecryptedMessage {
+        try {
+            val message = Message.parseFrom(envelope.message)
+            val decrypted = message.v1.decrypt(client.privateKeyBundleV1)
+
+            val encodedMessage = EncodedContent.parseFrom(decrypted)
+            val header = message.v1.header
+
+            return DecryptedMessage(
+                id = generateId(envelope),
+                encodedContent = encodedMessage,
+                senderAddress = header.sender.walletAddress,
+                sentAt = message.v1.sentAt
+            )
+        } catch (e: Exception) {
+            throw XMTPException("Error decrypting message", e)
+        }
+    }
+
+    fun decode(envelope: Envelope): DecodedMessage {
+        try {
+            val decryptedMessage = decrypt(envelope)
+
+            return DecodedMessage(
+                id = generateId(envelope),
+                client = client,
+                topic = envelope.contentTopic,
+                encodedContent = decryptedMessage.encodedContent,
+                senderAddress = decryptedMessage.senderAddress,
+                sent = decryptedMessage.sentAt
+            )
+        } catch (e: Exception) {
+            throw XMTPException("Error decoding message", e)
+        }
     }
 
     private fun decodeOrNull(envelope: Envelope): DecodedMessage? {

library/src/main/java/org/xmtp/android/library/ConversationV2.kt

@@ -13,7 +13,6 @@ import org.xmtp.android.library.messages.Envelope
 import org.xmtp.android.library.messages.EnvelopeBuilder
 import org.xmtp.android.library.messages.Message
 import org.xmtp.android.library.messages.MessageBuilder
-import org.xmtp.android.library.messages.MessageV2
 import org.xmtp.android.library.messages.MessageV2Builder
 import org.xmtp.android.library.messages.Pagination
 import org.xmtp.android.library.messages.PagingInfoSortDirection
@@ -22,6 +21,7 @@ import org.xmtp.android.library.messages.getPublicKeyBundle
 import org.xmtp.android.library.messages.walletAddress
 import org.xmtp.proto.message.api.v1.MessageApiOuterClass
 import org.xmtp.proto.message.contents.Invitation
+import uniffi.xmtp_dh.org.xmtp.android.library.messages.DecryptedMessage
 import java.util.Date
 
 data class ConversationV2(
@@ -77,6 +77,28 @@ data class ConversationV2(
         }
     }
 
+    fun decryptedMessages(
+        limit: Int? = null,
+        before: Date? = null,
+        after: Date? = null,
+        direction: PagingInfoSortDirection = MessageApiOuterClass.SortDirection.SORT_DIRECTION_DESCENDING,
+    ): List<DecryptedMessage> {
+        val pagination =
+            Pagination(limit = limit, before = before, after = after, direction = direction)
+        val envelopes = runBlocking { client.apiClient.envelopes(topic, pagination) }
+
+        return envelopes.map { envelope ->
+            val message = Message.parseFrom(envelope.message)
+            MessageV2Builder.buildDecrypt(
+                id = generateId(envelope = envelope),
+                topic,
+                message.v2,
+                keyMaterial,
+                client
+            )
+        }
+    }
+
     fun streamMessages(): Flow<DecodedMessage> = flow {
         client.subscribe(listOf(topic)).mapNotNull { decodeEnvelopeOrNull(envelope = it) }.collect {
             emit(it)
@@ -85,9 +107,13 @@ data class ConversationV2(
 
     fun decodeEnvelope(envelope: Envelope): DecodedMessage {
         val message = Message.parseFrom(envelope.message)
-        val decoded = decode(message.v2)
-        decoded.id = generateId(envelope)
-        return decoded
+        return MessageV2Builder.buildDecode(
+            generateId(envelope = envelope),
+            topic = topic,
+            message.v2,
+            keyMaterial = keyMaterial,
+            client = client
+        )
     }
 
     private fun decodeEnvelopeOrNull(envelope: Envelope): DecodedMessage? {
@@ -99,9 +125,6 @@ data class ConversationV2(
         }
     }
 
-    fun decode(message: MessageV2): DecodedMessage =
-        MessageV2Builder.buildDecode(message, keyMaterial = keyMaterial, topic = topic)
-
     fun <T> send(content: T, options: SendOptions? = null): String {
         val preparedMessage = prepareMessage(content = content, options = options)
         return send(preparedMessage)

library/src/main/java/org/xmtp/android/library/DecodedMessage.kt

@@ -6,16 +6,18 @@ import org.xmtp.proto.message.contents.Content
 import java.util.Date
 
 data class DecodedMessage(
+    var id: String = "",
+    val client: Client,
     var topic: String,
     var encodedContent: Content.EncodedContent,
     var senderAddress: String,
     var sent: Date
 ) {
-    var id: String = ""
     companion object {
-        fun preview(topic: String, body: String, senderAddress: String, sent: Date): DecodedMessage {
+        fun preview(client: Client, topic: String, body: String, senderAddress: String, sent: Date): DecodedMessage {
             val encoded = TextCodec().encode(content = body)
             return DecodedMessage(
+                client = client,
                 topic = topic,
                 encodedContent = encoded,
                 senderAddress = senderAddress,

library/src/main/java/org/xmtp/android/library/messages/DecryptedMessage.kt

@@ -0,0 +1,12 @@
+package uniffi.xmtp_dh.org.xmtp.android.library.messages
+
+import org.xmtp.android.library.codecs.EncodedContent
+import java.util.Date
+
+data class DecryptedMessage(
+    var id: String,
+    var encodedContent: EncodedContent,
+    var senderAddress: String,
+    var sentAt: Date,
+    var topic: String = ""
+)

library/src/main/java/org/xmtp/android/library/messages/MessageV2.kt

@@ -11,6 +11,7 @@ import org.xmtp.android.library.DecodedMessage
 import org.xmtp.android.library.KeyUtil
 import org.xmtp.android.library.XMTPException
 import org.xmtp.android.library.codecs.EncodedContent
+import uniffi.xmtp_dh.org.xmtp.android.library.messages.DecryptedMessage
 import java.math.BigInteger
 import java.util.Date
 
@@ -25,7 +26,36 @@ class MessageV2Builder {
             }.build()
         }
 
-        fun buildDecode(message: MessageV2, keyMaterial: ByteArray, topic: String): DecodedMessage {
+        fun buildDecode(
+            id: String,
+            topic: String,
+            message: MessageV2,
+            keyMaterial: ByteArray,
+            client: Client,
+        ): DecodedMessage {
+            try {
+                val decryptedMessage = buildDecrypt(id, topic, message, keyMaterial, client)
+
+                return DecodedMessage(
+                    id = id,
+                    client = client,
+                    topic = decryptedMessage.topic,
+                    encodedContent = decryptedMessage.encodedContent,
+                    senderAddress = decryptedMessage.senderAddress,
+                    sent = decryptedMessage.sentAt
+                )
+            } catch (e: Exception) {
+                throw XMTPException("Error decoding message", e)
+            }
+        }
+
+        fun buildDecrypt(
+            id: String,
+            topic: String,
+            message: MessageV2,
+            keyMaterial: ByteArray,
+            client: Client,
+        ): DecryptedMessage {
             val decrypted =
                 Crypto.decrypt(keyMaterial, message.ciphertext, message.headerBytes.toByteArray())
             val signed = SignedContent.parseFrom(decrypted)
@@ -68,16 +98,19 @@ class MessageV2Builder {
             if (key.walletAddress != (PublicKeyBuilder.buildFromSignedPublicKey(signed.sender.preKey).walletAddress)) {
                 throw XMTPException("Invalid signature")
             }
+
             val encodedMessage = EncodedContent.parseFrom(signed.payload)
             val header = MessageHeaderV2.parseFrom(message.headerBytes)
             if (header.topic != topic) {
                 throw XMTPException("Topic mismatch")
             }
-            return DecodedMessage(
-                topic = header.topic,
+
+            return DecryptedMessage(
+                id = id,
                 encodedContent = encodedMessage,
                 senderAddress = signed.sender.walletAddress,
-                sent = Date(header.createdNs / 1_000_000)
+                sentAt = Date(header.createdNs / 1_000_000),
+                topic = topic
             )
         }