feat(send): multi-file shares and receivers polish

Allow selecting multiple files on Android, desktop, and iOS and share them
as one transfer through the core multi-source path. Update the composer UI
for multi-file review, hide unfinished iOS receive methods, and surface
refusal reasons on the receivers list.

shared/src/iosMain/kotlin/com/vnidrop/app/core/FilePicker.ios.kt

@@ -23,12 +23,12 @@ private var retainedPickerDelegate: DocumentPickerDelegate? = null
 
 @Composable
 actual fun rememberShareFilePicker(
-	onFilePicked: (PickedShareFile) -> Unit,
+	onFilesPicked: (List<PickedShareFile>) -> Unit,
 	onError: (String) -> Unit,
-): ShareFilePicker = remember(onFilePicked, onError) {
+): ShareFilePicker = remember(onFilesPicked, onError) {
 	object : ShareFilePicker {
 		@OptIn(ExperimentalForeignApi::class)
-		override fun pickFile() {
+		override fun pickFiles() {
 			val presenter = UIApplication.sharedApplication.keyWindow?.rootViewController
 			if (presenter == null) {
 				onError("Could not find an iOS view controller for the document picker")
@@ -36,7 +36,11 @@ actual fun rememberShareFilePicker(
 			}
 
 			val picker = UIDocumentPickerViewController(forOpeningContentTypes = listOf(UTTypeItem), asCopy = false)
-			val delegate = DocumentPickerDelegate(onFilePicked, onError)
+			picker.allowsMultipleSelection = true
+			val delegate = DocumentPickerDelegate(
+				onFilesPicked = onFilesPicked,
+				onError = onError,
+			)
 			retainedPickerDelegate = delegate
 			picker.delegate = delegate
 			picker.modalPresentationStyle = UIModalPresentationFormSheet
@@ -61,7 +65,8 @@ actual fun rememberReceiveFolderPicker(
 
 			val picker = UIDocumentPickerViewController(forOpeningContentTypes = listOf(UTTypeFolder), asCopy = false)
 			val delegate = DocumentPickerDelegate(
-				onFilePicked = { folder ->
+				onFilesPicked = { folders ->
+					val folder = folders.firstOrNull() ?: return@DocumentPickerDelegate
 					onFolderPicked(
 						ReceiveFolder(
 							kind = ReceiveFolderKind.IosSecurityScopedUrl,
@@ -81,14 +86,12 @@ actual fun rememberReceiveFolderPicker(
 }
 
 private class DocumentPickerDelegate(
-	private val onFilePicked: (PickedShareFile) -> Unit,
+	private val onFilesPicked: (List<PickedShareFile>) -> Unit,
 	private val onError: (String) -> Unit,
 ) : NSObject(), UIDocumentPickerDelegateProtocol {
 	override fun documentPicker(controller: UIDocumentPickerViewController, didPickDocumentsAtURLs: List<*>) {
-		val url = didPickDocumentsAtURLs.firstOrNull() as? NSURL
-		if (url == null) {
-			onError("The selected iOS document URL was invalid")
-		} else {
+		val files = didPickDocumentsAtURLs.mapNotNull { raw ->
+			val url = raw as? NSURL ?: return@mapNotNull null
 			val displayName = url.lastPathComponent ?: "transfer"
 			val didStartAccess = url.startAccessingSecurityScopedResource()
 			val sizeBytes = try {
@@ -97,15 +100,18 @@ private class DocumentPickerDelegate(
 			} finally {
 				if (didStartAccess) url.stopAccessingSecurityScopedResource()
 			}
-			onFilePicked(
-				PickedShareFile(
-					url.absoluteString ?: url.path.orEmpty(),
-					displayName,
-					sizeBytes,
-					nativeFileIcon(url),
-				),
+			PickedShareFile(
+				url.absoluteString ?: url.path.orEmpty(),
+				displayName,
+				sizeBytes,
+				nativeFileIcon(url),
 			)
 		}
+		if (files.isEmpty()) {
+			onError("The selected iOS document URL was invalid")
+		} else {
+			onFilesPicked(files)
+		}
 		retainedPickerDelegate = null
 	}
 

shared/src/iosMain/kotlin/com/vnidrop/app/core/FileSystemService.ios.kt

@@ -43,19 +43,24 @@ private class IosFileSystemService : FileSystemService {
 
 	override fun createReceiveOutputSink(folder: ReceiveFolder): ReceiveOutputSink? = null
 
-	override suspend fun sharePickedFile(
+	override suspend fun sharePickedFiles(
 		repository: CoreGateway,
-		file: PickedShareFile,
+		files: List<PickedShareFile>,
 		transferName: String,
 		senderName: String,
 		accessPolicy: ShareAccessPolicy,
-	): Result<Share> = repository.shareSecurityScopedFileUrl(
-		file.value,
-		file.displayName,
-		transferName,
-		senderName,
-		accessPolicy,
-	)
+	): Result<Share> {
+		require(files.isNotEmpty()) { "Select at least one file to share" }
+		val sources = files.map { file ->
+			uniffi.vnidrop.ShareSource(
+				kind = uniffi.vnidrop.SourceKind.IOS_SECURITY_SCOPED_URL,
+				value = file.value,
+				displayName = file.displayName,
+				isDirectory = false,
+			)
+		}
+		return repository.shareSources(sources, transferName, senderName, accessPolicy)
+	}
 
 	private fun validateSecurityScopedUrl(value: String): FolderAccessStatus {
 		val url = NSURL.URLWithString(value) ?: NSURL.fileURLWithPath(value)

shared/src/iosMain/kotlin/com/vnidrop/app/feature/receive/ReceiveInvitationActions.ios.kt

@@ -19,8 +19,9 @@ private var retainedInvitationDelegate: InvitationDocumentDelegate? = null
 actual fun rememberReceiveInvitationActions(): ReceiveInvitationActions = remember {
 	object : ReceiveInvitationActions {
 		override val fileAvailability = ReceiveMethodAvailability.Available
-		override val qrAvailability = ReceiveMethodAvailability.Unavailable
-		override val nfcAvailability = ReceiveMethodAvailability.Unavailable
+		// Hide unfinished iOS methods so the method list only shows what works.
+		override val qrAvailability = ReceiveMethodAvailability.Hidden
+		override val nfcAvailability = ReceiveMethodAvailability.Hidden
 
 		@OptIn(ExperimentalForeignApi::class)
 		override fun pickInvitation(onResult: (Result<String>) -> Unit) {