feat(media): encrypted file sharing in desktop DMs (NIP-17 Phase 6)

Add full send + receive encrypted media support in desktop DM chat: - Paperclip attach button and drag-and-drop in ChatPane (NIP-17 mode only) - AES-GCM encryption before upload to Blossom server - ChatMessageEncryptedFileHeaderEvent (kind 15) wrapped in GiftWrap - sendNip17EncryptedFile() added to IAccount interface and implementations - DesktopUploadOrchestrator.uploadEncrypted() with proper encrypted hash - DesktopBlossomClient ByteArray upload overload for encrypted blobs - LRU cache in EncryptedMediaService to avoid re-downloading - Error handling: retry on failure, disable send during upload Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2026-03-19 06:53:36 +02:00
parent c90bf8f610
commit 24d4073b9b
9 changed files with 343 additions and 27 deletions
@@ -33,6 +33,7 @@ import com.vitorpamplona.quartz.nip01Core.signers.EventTemplate
 import com.vitorpamplona.quartz.nip01Core.signers.NostrSigner
 import com.vitorpamplona.quartz.nip04Dm.messages.PrivateDmEvent
 import com.vitorpamplona.quartz.nip17Dm.NIP17Factory
+import com.vitorpamplona.quartz.nip17Dm.files.ChatMessageEncryptedFileHeaderEvent
 import com.vitorpamplona.quartz.nip17Dm.messages.ChatMessageEvent
 import com.vitorpamplona.quartz.nip47WalletConnect.LnZapPaymentRequestEvent
 import com.vitorpamplona.quartz.nip47WalletConnect.LnZapPaymentResponseEvent
@@ -156,6 +157,37 @@ class DesktopIAccount(
        scope.launch { dmSendTracker.sendBatch(batch) }
    }

+    override suspend fun sendNip17EncryptedFile(template: EventTemplate<ChatMessageEncryptedFileHeaderEvent>) {
+        if (!isWriteable()) return
+
+        val result = NIP17Factory().createEncryptedFileNIP17(template, signer)
+
+        // Optimistic local add
+        val innerEvent = result.msg as ChatMessageEncryptedFileHeaderEvent
+        addEventToChatroom(innerEvent, innerEvent.chatroomKey(pubKey))
+
+        // Collect wraps with target relays and send
+        val batch =
+            result.wraps.map { wrap ->
+                val recipientKey = wrap.recipientPubKey()
+                val targetRelays =
+                    if (recipientKey != null) {
+                        val dmRelays =
+                            localCache
+                                .getOrCreateUser(recipientKey)
+                                .dmInboxRelays()
+                                ?.toSet()
+                        dmRelays?.ifEmpty { null }
+                            ?: relayManager.connectedRelays.value
+                    } else {
+                        relayManager.connectedRelays.value
+                    }
+                wrap to targetRelays
+            }
+
+        scope.launch { dmSendTracker.sendBatch(batch) }
+    }
+
    override suspend fun sendGiftWraps(wraps: List<GiftWrapEvent>) {
        val batch =
            wraps.map { wrap ->
@@ -25,24 +25,31 @@ import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
 import okhttp3.OkHttpClient
 import okhttp3.Request
+import java.util.concurrent.ConcurrentHashMap

 /**
 * Handles decryption of media files for NIP-17 DMs.
 * Uses AESGCM cipher from quartz (commonMain).
+ * Caches decrypted bytes in memory to avoid re-downloading on recomposition.
 */
 object EncryptedMediaService {
    private val httpClient = OkHttpClient()
+    private val cache = ConcurrentHashMap<String, ByteArray>()
+    private const val MAX_CACHE_ENTRIES = 20

    /**
     * Download and decrypt an encrypted file from a URL.
+     * Results are cached by URL to avoid re-downloading on scroll/recomposition.
     * Returns the decrypted bytes.
     */
    suspend fun downloadAndDecrypt(
        url: String,
        keyBytes: ByteArray,
        nonce: ByteArray,
-    ): ByteArray =
-        withContext(Dispatchers.IO) {
+    ): ByteArray {
+        cache[url]?.let { return it }
+
+        return withContext(Dispatchers.IO) {
            val request = Request.Builder().url(url).build()
            val response = httpClient.newCall(request).execute()
            val encryptedBytes =
@@ -52,6 +59,15 @@ object EncryptedMediaService {
                }

            val cipher = AESGCM(keyBytes, nonce)
-            cipher.decrypt(encryptedBytes)
+            val decrypted = cipher.decrypt(encryptedBytes)
+
+            // Evict oldest entries if cache is full
+            if (cache.size >= MAX_CACHE_ENTRIES) {
+                cache.keys.firstOrNull()?.let { cache.remove(it) }
+            }
+            cache[url] = decrypted
+
+            decrypted
        }
+    }
 }
@@ -28,6 +28,7 @@ import okhttp3.MediaType.Companion.toMediaType
 import okhttp3.OkHttpClient
 import okhttp3.Request
 import okhttp3.RequestBody
+import okhttp3.RequestBody.Companion.toRequestBody
 import okio.BufferedSink
 import okio.source
 import java.io.File
@@ -62,6 +63,37 @@ class DesktopBlossomClient(

            authHeader?.let { requestBuilder.addHeader("Authorization", it) }

+            val response = okHttpClient.newCall(requestBuilder.build()).execute()
+            response.use {
+                if (!it.isSuccessful) {
+                    val reason = it.headers["X-Reason"] ?: it.code.toString()
+                    throw RuntimeException("Upload failed ($serverBaseUrl): $reason")
+                }
+                JsonMapper.fromJson<BlossomUploadResult>(it.body.string())
+            }
+        }
+
+    /**
+     * Upload raw bytes (e.g. encrypted blobs) to a Blossom server.
+     */
+    suspend fun upload(
+        bytes: ByteArray,
+        contentType: String,
+        serverBaseUrl: String,
+        authHeader: String?,
+    ): BlossomUploadResult =
+        withContext(Dispatchers.IO) {
+            val apiUrl = serverBaseUrl.removeSuffix("/") + "/upload"
+            val requestBody = bytes.toRequestBody(contentType.toMediaType())
+
+            val requestBuilder =
+                Request
+                    .Builder()
+                    .url(apiUrl)
+                    .put(requestBody)
+
+            authHeader?.let { requestBuilder.addHeader("Authorization", it) }
+
            val response = okHttpClient.newCall(requestBuilder.build()).execute()
            response.use {
                if (!it.isSuccessful) {
@@ -20,8 +20,11 @@
 */
 package com.vitorpamplona.amethyst.desktop.service.upload

+import com.vitorpamplona.quartz.nip01Core.core.toHexKey
 import com.vitorpamplona.quartz.nip01Core.signers.NostrSigner
 import com.vitorpamplona.quartz.nipB7Blossom.BlossomUploadResult
+import com.vitorpamplona.quartz.utils.ciphers.AESGCM
+import com.vitorpamplona.quartz.utils.sha256.sha256
 import java.io.File

 data class UploadResult(
@@ -29,6 +32,13 @@ data class UploadResult(
    val metadata: MediaMetadata,
 )

+data class EncryptedUploadResult(
+    val blossom: BlossomUploadResult,
+    val metadata: MediaMetadata,
+    val encryptedHash: String,
+    val encryptedSize: Int,
+)
+
 class DesktopUploadOrchestrator(
    private val client: DesktopBlossomClient = DesktopBlossomClient(),
 ) {
@@ -75,4 +85,52 @@ class DesktopUploadOrchestrator(

        return UploadResult(blossom = result, metadata = metadata)
    }
+
+    /**
+     * Upload a file encrypted with AES-GCM for NIP-17 DM file sharing.
+     * Computes pre-encryption metadata (dimensions, blurhash), encrypts bytes,
+     * then uploads the encrypted blob to Blossom.
+     */
+    suspend fun uploadEncrypted(
+        file: File,
+        cipher: AESGCM,
+        serverBaseUrl: String,
+        signer: NostrSigner,
+    ): EncryptedUploadResult {
+        // 1. Compute pre-encryption metadata (dimensions, blurhash, mime, originalHash)
+        val metadata = DesktopMediaMetadata.compute(file)
+
+        // 2. Read file bytes and encrypt
+        val plaintext = file.readBytes()
+        val encrypted = cipher.encrypt(plaintext)
+
+        // 3. Compute SHA256 of ENCRYPTED blob (not plaintext)
+        val encryptedHash = sha256(encrypted).toHexKey()
+        val encryptedSize = encrypted.size
+
+        // 4. Create Blossom auth with encrypted hash and size
+        val authHeader =
+            DesktopBlossomAuth.createUploadAuth(
+                hash = encryptedHash,
+                size = encryptedSize.toLong(),
+                alt = "Encrypted upload",
+                signer = signer,
+            )
+
+        // 5. Upload encrypted blob as opaque binary
+        val result =
+            client.upload(
+                bytes = encrypted,
+                contentType = "application/octet-stream",
+                serverBaseUrl = serverBaseUrl,
+                authHeader = authHeader,
+            )
+
+        return EncryptedUploadResult(
+            blossom = result,
+            metadata = metadata,
+            encryptedHash = encryptedHash,
+            encryptedSize = encryptedSize,
+        )
+    }
 }
@@ -20,6 +20,8 @@
 */
 package com.vitorpamplona.amethyst.desktop.ui.chats

+import androidx.compose.foundation.border
+import androidx.compose.foundation.draganddrop.dragAndDropTarget
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
@@ -38,6 +40,7 @@ import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.foundation.text.selection.SelectionContainer
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.automirrored.filled.Send
+import androidx.compose.material.icons.filled.AttachFile
 import androidx.compose.material.icons.filled.Lock
 import androidx.compose.material.icons.filled.LockOpen
 import androidx.compose.material.icons.outlined.AddReaction
@@ -53,6 +56,7 @@ import androidx.compose.runtime.Composable
 import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.collectAsState
 import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateListOf
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.rememberCoroutineScope
@@ -60,6 +64,8 @@ import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.ExperimentalComposeUiApi
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.draganddrop.DragAndDropEvent
+import androidx.compose.ui.draganddrop.DragAndDropTarget
 import androidx.compose.ui.input.key.Key
 import androidx.compose.ui.input.key.KeyEventType
 import androidx.compose.ui.input.key.isCtrlPressed
@@ -88,15 +94,28 @@ import com.vitorpamplona.amethyst.commons.ui.feeds.FeedState
 import com.vitorpamplona.amethyst.commons.util.toTimeAgo
 import com.vitorpamplona.amethyst.commons.viewmodels.ChatNewMessageState
 import com.vitorpamplona.amethyst.commons.viewmodels.ChatroomFeedViewModel
+import com.vitorpamplona.amethyst.desktop.DesktopPreferences
+import com.vitorpamplona.amethyst.desktop.service.upload.DesktopUploadOrchestrator
+import com.vitorpamplona.amethyst.desktop.ui.media.DesktopFilePicker
+import com.vitorpamplona.amethyst.desktop.ui.media.MediaAttachmentRow
 import com.vitorpamplona.quartz.nip01Core.hints.EventHintBundle
 import com.vitorpamplona.quartz.nip04Dm.messages.PrivateDmEvent
 import com.vitorpamplona.quartz.nip17Dm.NIP17Factory
 import com.vitorpamplona.quartz.nip17Dm.base.ChatroomKey
 import com.vitorpamplona.quartz.nip17Dm.files.ChatMessageEncryptedFileHeaderEvent
+import com.vitorpamplona.quartz.nip94FileMetadata.tags.DimensionTag
+import com.vitorpamplona.quartz.utils.ciphers.AESGCM
 import kotlinx.coroutines.launch
+import java.awt.datatransfer.DataFlavor
+import java.awt.dnd.DnDConstants
+import java.awt.dnd.DropTargetDropEvent
+import java.io.File

 private val isMacOS = System.getProperty("os.name").lowercase().contains("mac")

+private val MEDIA_EXTENSIONS =
+    setOf("jpg", "jpeg", "png", "gif", "webp", "svg", "avif", "mp4", "webm", "mov", "mp3", "ogg", "wav", "flac")
+
 /**
 * Right panel of the DM split-pane layout (flexible width).
 *
@@ -112,6 +131,7 @@ private val isMacOS = System.getProperty("os.name").lowercase().contains("mac")
 * @param messageState ChatNewMessageState for composition
 * @param onNavigateToProfile Called when user clicks on a profile
 */
+@OptIn(ExperimentalComposeUiApi::class)
@Composable
 fun ChatPane(
    roomKey: ChatroomKey,
@@ -129,6 +149,41 @@ fun ChatPane(
    val isNip17 by messageState.nip17.collectAsState()
    val requiresNip17 by messageState.requiresNip17.collectAsState()

+    // File attachment state
+    val attachedFiles = remember { mutableStateListOf<File>() }
+    var isUploading by remember { mutableStateOf(false) }
+
+    // Drag-and-drop target for file attachments (NIP-17 only)
+    var isDragOver by remember { mutableStateOf(false) }
+    val dropTarget =
+        remember {
+            object : DragAndDropTarget {
+                override fun onDrop(event: DragAndDropEvent): Boolean {
+                    isDragOver = false
+                    val dropEvent = event.nativeEvent as? DropTargetDropEvent ?: return false
+                    dropEvent.acceptDrop(DnDConstants.ACTION_COPY)
+                    val transferable = dropEvent.transferable
+                    if (transferable.isDataFlavorSupported(DataFlavor.javaFileListFlavor)) {
+                        @Suppress("UNCHECKED_CAST")
+                        val files = transferable.getTransferData(DataFlavor.javaFileListFlavor) as List<File>
+                        attachedFiles.addAll(files.filter { it.extension.lowercase() in MEDIA_EXTENSIONS })
+                        dropEvent.dropComplete(true)
+                        return true
+                    }
+                    dropEvent.dropComplete(false)
+                    return false
+                }
+
+                override fun onStarted(event: DragAndDropEvent) {
+                    isDragOver = true
+                }
+
+                override fun onEnded(event: DragAndDropEvent) {
+                    isDragOver = false
+                }
+            }
+        }
+
    // Resolve users for the header
    val users = roomKey.users.mapNotNull { cacheProvider.getUserIfExists(it) as? User }
    val isGroup = users.size > 1
@@ -138,7 +193,21 @@ fun ChatPane(
        messageState.load(roomKey)
    }

-    Column(modifier = modifier.fillMaxSize()) {
+    Column(
+        modifier =
+            modifier
+                .fillMaxSize()
+                .dragAndDropTarget(
+                    shouldStartDragAndDrop = { isNip17 },
+                    target = dropTarget,
+                ).then(
+                    if (isDragOver) {
+                        Modifier.border(2.dp, MaterialTheme.colorScheme.primary, RoundedCornerShape(8.dp))
+                    } else {
+                        Modifier
+                    },
+                ),
+    ) {
        // Header
        if (isGroup) {
            GroupChatroomHeader(
@@ -225,17 +294,59 @@ fun ChatPane(

        HorizontalDivider()

+        // File attachment row (only when NIP-17 and files attached)
+        if (isNip17 && attachedFiles.isNotEmpty()) {
+            MediaAttachmentRow(
+                attachedFiles = attachedFiles,
+                isUploading = isUploading,
+                onAttach = {
+                    val files = DesktopFilePicker.pickMediaFiles()
+                    attachedFiles.addAll(files)
+                },
+                onPaste = {},
+                onRemove = { attachedFiles.remove(it) },
+            )
+        }
+
        // Message input
        MessageInput(
            messageText = messageText.text,
            isNip17 = isNip17,
            requiresNip17 = requiresNip17,
-            canSend = messageState.canSend,
+            canSend = messageState.canSend || attachedFiles.isNotEmpty(),
+            isUploading = isUploading,
+            hasAttachments = attachedFiles.isNotEmpty(),
            onMessageChange = { messageState.updateMessage(messageText.copy(text = it)) },
            onToggleNip17 = { messageState.toggleNip17() },
+            onAttach = {
+                val files = DesktopFilePicker.pickMediaFiles()
+                attachedFiles.addAll(files)
+            },
            onSend = {
                scope.launch {
-                    if (messageState.send()) {
+                    if (attachedFiles.isNotEmpty()) {
+                        isUploading = true
+                        try {
+                            sendEncryptedFiles(
+                                files = attachedFiles.toList(),
+                                roomKey = roomKey,
+                                account = account,
+                                cacheProvider = cacheProvider,
+                            )
+                            attachedFiles.clear()
+                        } catch (e: Exception) {
+                            // Keep files in attachment row for retry
+                            println("Encrypted file send failed: ${e.message}")
+                        } finally {
+                            isUploading = false
+                        }
+                    }
+                    // Also send text message if present
+                    if (messageState.canSend) {
+                        if (messageState.send()) {
+                            messageState.clear()
+                        }
+                    } else if (attachedFiles.isEmpty()) {
                        messageState.clear()
                    }
                }
@@ -529,8 +640,11 @@ private fun MessageInput(
    isNip17: Boolean,
    requiresNip17: Boolean,
    canSend: Boolean,
+    isUploading: Boolean = false,
+    hasAttachments: Boolean = false,
    onMessageChange: (String) -> Unit,
    onToggleNip17: () -> Unit,
+    onAttach: () -> Unit = {},
    onSend: () -> Unit,
 ) {
    Column(modifier = Modifier.fillMaxWidth().padding(8.dp)) {
@@ -539,6 +653,26 @@ private fun MessageInput(
            verticalAlignment = Alignment.CenterVertically,
            horizontalArrangement = Arrangement.spacedBy(8.dp),
        ) {
+            // Paperclip attach button (NIP-17 only)
+            if (isNip17) {
+                IconButton(
+                    onClick = onAttach,
+                    enabled = !isUploading,
+                    modifier = Modifier.size(40.dp),
+                ) {
+                    Icon(
+                        Icons.Default.AttachFile,
+                        contentDescription = "Attach file",
+                        tint =
+                            if (isUploading) {
+                                MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 0.3f)
+                            } else {
+                                MaterialTheme.colorScheme.primary
+                            },
+                    )
+                }
+            }
+
            OutlinedTextField(
                value = messageText,
                onValueChange = onMessageChange,
@@ -564,14 +698,14 @@ private fun MessageInput(

            IconButton(
                onClick = onSend,
-                enabled = canSend,
+                enabled = canSend && !isUploading,
                modifier = Modifier.size(40.dp),
            ) {
                Icon(
                    Icons.AutoMirrored.Filled.Send,
                    contentDescription = "Send",
                    tint =
-                        if (canSend) {
+                        if (canSend && !isUploading) {
                            MaterialTheme.colorScheme.primary
                        } else {
                            MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 0.3f)
@@ -625,3 +759,43 @@ private fun MessageInput(
        }
    }
 }
+
+/**
+ * Encrypts and uploads files, then sends each as a ChatMessageEncryptedFileHeaderEvent (kind 15)
+ * wrapped in GiftWrap for each recipient.
+ */
+private suspend fun sendEncryptedFiles(
+    files: List<File>,
+    roomKey: ChatroomKey,
+    account: IAccount,
+    cacheProvider: ICacheProvider,
+) {
+    val orchestrator = DesktopUploadOrchestrator()
+    val server = DesktopPreferences.preferredBlossomServer
+    val recipients = roomKey.users.mapNotNull { cacheProvider.getUserIfExists(it) as? User }.map { it.toPTag() }
+
+    for (file in files) {
+        val cipher = AESGCM()
+        val result = orchestrator.uploadEncrypted(file, cipher, server, account.signer)
+        val url = result.blossom.url ?: continue
+
+        val template =
+            ChatMessageEncryptedFileHeaderEvent.build(
+                to = recipients,
+                url = url,
+                cipher = cipher,
+                mimeType = result.metadata.mimeType,
+                hash = result.encryptedHash,
+                size = result.encryptedSize,
+                dimension =
+                    if (result.metadata.width != null && result.metadata.height != null) {
+                        DimensionTag(result.metadata.width, result.metadata.height)
+                    } else {
+                        null
+                    },
+                blurhash = result.metadata.blurhash,
+                originalHash = result.metadata.sha256,
+            )
+        account.sendNip17EncryptedFile(template)
+    }
+}