Simplify PR: Focus on audio+image, fix EXIF stripping, remove file transfers

- Fix critical EXIF privacy issue in iOS image processing
  - Both iOS and macOS now use CGImageDestination for metadata stripping
  - Shared encodeJPEG function ensures no GPS, camera, or metadata leaks

- Remove file transfer functionality to simplify PR scope
  - Deleted FileAttachmentView
  - Removed sendFileAttachment from ChatViewModel
  - Removed file picker UI from ContentView
  - Simplified attachment dialog to image only (iOS) or voice only

- Keep focused media features:
  - Voice recording and playback
  - Image sending with progressive reveal
  - Binary protocol for media transfer

bitchat/Features/media/ImageUtils.swift

@@ -1,10 +1,10 @@
 import Foundation
+import ImageIO
+import UniformTypeIdentifiers
 #if os(iOS)
 import UIKit
 #else
 import AppKit
-import ImageIO
-import UniformTypeIdentifiers
 #endif
 
 enum ImageUtilsError: Error {
@@ -40,19 +40,30 @@ enum ImageUtils {
     #if os(iOS)
     static func processImage(_ image: UIImage, maxDimension: CGFloat = 512) throws -> URL {
         return try autoreleasepool {
+            // Scale the image first
             let scaled = scaledImage(image, maxDimension: maxDimension)
-            var quality = compressionQuality
+
-            guard var jpegData = scaled.jpegData(compressionQuality: quality) else {
+            // Get CGImage from UIImage - this is the key to stripping metadata
+            guard let cgImage = scaled.cgImage else {
                 throw ImageUtilsError.encodingFailed
             }
+
+            // Use CGImageDestination to encode without metadata (same as macOS)
+            var quality = compressionQuality
+            guard var jpegData = encodeJPEG(from: cgImage, quality: quality) else {
+                throw ImageUtilsError.encodingFailed
+            }
+
+            // Compress to target size
             while jpegData.count > targetImageBytes && quality > 0.3 {
                 quality -= 0.1
                 autoreleasepool {
-                    if let next = scaled.jpegData(compressionQuality: quality) {
+                    if let next = encodeJPEG(from: cgImage, quality: quality) {
                         jpegData = next
                     }
                 }
             }
+
             let outputURL = try makeOutputURL()
             try jpegData.write(to: outputURL, options: .atomic)
             return outputURL
@@ -65,12 +76,35 @@ enum ImageUtils {
         guard maxSide > maxDimension else { return image }
         let scale = maxDimension / maxSide
         let newSize = CGSize(width: size.width * scale, height: size.height * scale)
+
+        // Draw into a new context to get a clean CGImage without metadata
         UIGraphicsBeginImageContextWithOptions(newSize, true, 1.0)
         image.draw(in: CGRect(origin: .zero, size: newSize))
         let rendered = UIGraphicsGetImageFromCurrentImageContext()
         UIGraphicsEndImageContext()
         return rendered ?? image
     }
+
+    // Shared EXIF-stripping JPEG encoder for both iOS and macOS
+    private static func encodeJPEG(from cgImage: CGImage, quality: CGFloat) -> Data? {
+        guard let data = CFDataCreateMutable(nil, 0) else {
+            return nil
+        }
+        guard let destination = CGImageDestinationCreateWithData(data, UTType.jpeg.identifier as CFString, 1, nil) else {
+            return nil
+        }
+        // Security: Strip ALL metadata (EXIF, GPS, TIFF, IPTC, XMP)
+        // By only specifying compression quality and no metadata keys,
+        // we ensure a clean JPEG with no privacy-leaking information
+        let options: [CFString: Any] = [
+            kCGImageDestinationLossyCompressionQuality: quality
+        ]
+        CGImageDestinationAddImage(destination, cgImage, options as CFDictionary)
+        guard CGImageDestinationFinalize(destination) else {
+            return nil
+        }
+        return data as Data
+    }
     #else
     static func processImage(_ image: NSImage, maxDimension: CGFloat = 512) throws -> URL {
         return try autoreleasepool {
@@ -130,6 +164,7 @@ enum ImageUtils {
         return scaledImage
     }
 
+    // Shared EXIF-stripping JPEG encoder for both iOS and macOS
     private static func encodeJPEG(from cgImage: CGImage, quality: CGFloat) -> Data? {
         guard let data = CFDataCreateMutable(nil, 0) else {
             return nil
@@ -137,8 +172,9 @@ enum ImageUtils {
         guard let destination = CGImageDestinationCreateWithData(data, UTType.jpeg.identifier as CFString, 1, nil) else {
             return nil
         }
-        // Security H2: Strip ALL metadata (EXIF, GPS, TIFF, IPTC, XMP)
+        // Security: Strip ALL metadata (EXIF, GPS, TIFF, IPTC, XMP)
-        // Don't add any metadata dictionary keys - fresh CGContext ensures clean image
+        // By only specifying compression quality and no metadata keys,
+        // we ensure a clean JPEG with no privacy-leaking information
         let options: [CFString: Any] = [
             kCGImageDestinationLossyCompressionQuality: quality
         ]

bitchat/ViewModels/ChatViewModel.swift

@@ -2503,65 +2503,6 @@ final class ChatViewModel: ObservableObject, BitchatDelegate {
         }
     }
 
-    @MainActor
-    func sendFileAttachment(from sourceURL: URL) {
-        let targetPeer = selectedPrivateChatPeer
-
-        Task.detached(priority: .userInitiated) { [weak self] in
-            guard let self = self else { return }
-            defer { try? FileManager.default.removeItem(at: sourceURL) }
-            var destinationURL: URL?
-            do {
-                // Security H1: Check file size BEFORE reading into memory
-                let attrs = try FileManager.default.attributesOfItem(atPath: sourceURL.path)
-                guard let fileSize = attrs[.size] as? Int else {
-                    throw MediaSendError.encodingFailed
-                }
-                guard FileTransferLimits.isValidPayload(fileSize) else {
-                    throw MediaSendError.tooLarge
-                }
-
-                let data = try Data(contentsOf: sourceURL)
-
-                let destination = try self.prepareOutgoingFileCopy(from: sourceURL, data: data)
-                destinationURL = destination
-                let packet = BitchatFilePacket(
-                    fileName: destination.lastPathComponent,
-                    fileSize: UInt64(data.count),
-                    mimeType: self.mimeType(for: destination),
-                    content: data
-                )
-                guard packet.encode() != nil else {
-                    try? FileManager.default.removeItem(at: destination)
-                    throw MediaSendError.encodingFailed
-                }
-
-                await MainActor.run {
-                    let message = self.enqueueMediaMessage(content: "[file] \(destination.lastPathComponent)", targetPeer: targetPeer?.id)
-                    let messageID = message.id
-                    let transferId = self.makeTransferID(messageID: messageID)
-                    self.registerTransfer(transferId: transferId, messageID: messageID)
-                    if let peerID = targetPeer {
-                        self.meshService.sendFilePrivate(packet, to: peerID, transferId: transferId)
-                    } else {
-                        self.meshService.sendFileBroadcast(packet, transferId: transferId)
-                    }
-                }
-            } catch MediaSendError.tooLarge {
-                await MainActor.run {
-                    self.addSystemMessage("File is too large to send.")
-                }
-            } catch {
-                if let destination = destinationURL {
-                    try? FileManager.default.removeItem(at: destination)
-                }
-                SecureLogger.error("File attachment send failed: \(error)", category: .session)
-                await MainActor.run {
-                    self.addSystemMessage("Failed to send file.")
-                }
-            }
-        }
-    }
 
     @MainActor
     func cancelMediaSend(messageID: String) {
@@ -2748,55 +2689,6 @@ final class ChatViewModel: ObservableObject, BitchatDelegate {
         }
     }
 
-    private func prepareOutgoingFileCopy(from sourceURL: URL, data: Data) throws -> URL {
-        let base = try applicationFilesDirectory().appendingPathComponent("files/outgoing", isDirectory: true)
-        try FileManager.default.createDirectory(at: base, withIntermediateDirectories: true, attributes: nil)
-
-        let rawName = sourceURL.lastPathComponent
-        let sanitized = sanitizeOutgoingFileName(rawName.isEmpty ? "file" : rawName)
-        var destination = base.appendingPathComponent(sanitized)
-        var counter = 1
-        while FileManager.default.fileExists(atPath: destination.path) {
-            let baseName = (sanitized as NSString).deletingPathExtension
-            let ext = (sanitized as NSString).pathExtension
-            let newName: String
-            if ext.isEmpty {
-                newName = "\(baseName) (\(counter))"
-            } else {
-                newName = "\(baseName) (\(counter)).\(ext)"
-            }
-            destination = base.appendingPathComponent(newName)
-            counter += 1
-        }
-
-        try data.write(to: destination, options: .atomic)
-        return destination
-    }
-
-    private func sanitizeOutgoingFileName(_ name: String) -> String {
-        var candidate = name
-        candidate = candidate.replacingOccurrences(of: "\\", with: "/")
-        candidate = candidate.components(separatedBy: "/").last ?? name
-        candidate = candidate.trimmingCharacters(in: .whitespacesAndNewlines)
-        if candidate.isEmpty { candidate = "file" }
-        let invalid = CharacterSet(charactersIn: "<>:\"|?*")
-        candidate = candidate.components(separatedBy: invalid).joined(separator: "_")
-        if candidate.isEmpty { candidate = "file" }
-        if (candidate as NSString).pathExtension.isEmpty {
-            candidate += ".bin"
-        }
-        return candidate
-    }
-
-    private func mimeType(for url: URL) -> String {
-        let ext = url.pathExtension.lowercased()
-        if !ext.isEmpty,
-           let type = UTType(filenameExtension: ext),
-           let mime = type.preferredMIMEType {
-            return mime
-        }
-        return "application/octet-stream"
-    }
 
     private func applicationFilesDirectory() throws -> URL {
         let base = try FileManager.default.url(for: .applicationSupportDirectory, in: .userDomainMask, appropriateFor: nil, create: true)

bitchat/Views/ContentView.swift

@@ -71,7 +71,6 @@ struct ContentView: View {
     @State private var recordingDuration: TimeInterval = 0
     @State private var recordingTimer: Timer?
     @State private var recordingStartDate: Date?
-    @State private var showFileImporter = false
 #if os(iOS)
     @State private var showPhotoPicker = false
     @State private var selectedPhotoPickerItem: PhotosPickerItem?
@@ -216,9 +215,6 @@ struct ContentView: View {
             Task { await handlePhotoSelection(item) }
         }
 #endif
-        .fileImporter(isPresented: $showFileImporter, allowedContentTypes: [.data], allowsMultipleSelection: false) { result in
-            handleImportResult(result, handler: handleImportedFile)
-        }
         .sheet(isPresented: Binding(
             get: { imagePreviewURL != nil },
             set: { presenting in if !presenting { imagePreviewURL = nil } }
@@ -234,10 +230,6 @@ struct ContentView: View {
                 DispatchQueue.main.async { showPhotoPicker = true }
             }
 #endif
-            Button("File") {
-                showAttachmentActions = false
-                DispatchQueue.main.async { showFileImporter = true }
-            }
             Button("Cancel", role: .cancel) {}
         }
         .alert("Recording Error", isPresented: $showRecordingAlert, actions: {
@@ -1547,11 +1539,10 @@ struct ContentView: View {
 private enum MessageMedia {
     case voice(URL)
     case image(URL)
-    case file(URL)
 
     var url: URL {
         switch self {
-        case .voice(let url), .image(let url), .file(let url):
+        case .voice(let url), .image(let url):
             return url
         }
     }
@@ -1589,13 +1580,6 @@ private extension ContentView {
             let url = baseDirectory.appendingPathComponent(subdir, isDirectory: true).appendingPathComponent(filename)
             return .image(url)
         }
-        if message.content.hasPrefix("[file] ") {
-            let filename = String(message.content.dropFirst("[file] ".count)).trimmingCharacters(in: .whitespacesAndNewlines)
-            guard !filename.isEmpty else { return nil }
-            let subdir = message.sender == viewModel.nickname ? "files/outgoing" : "files/incoming"
-            let url = baseDirectory.appendingPathComponent(subdir, isDirectory: true).appendingPathComponent(filename)
-            return .file(url)
-        }
         return nil
     }
 
@@ -1687,13 +1671,6 @@ private extension ContentView {
                         } : nil
                     )
                     .frame(maxWidth: 280)
-                case .file(let url):
-                    FileAttachmentView(
-                        url: url,
-                        isSending: state.isSending,
-                        progress: state.progress,
-                        onCancel: cancelAction
-                    )
                 }
             }
         }
@@ -2024,24 +2001,6 @@ private extension ContentView {
     }
 #endif
 
-    func handleImportedFile(url: URL) async {
-        do {
-            let fileManager = FileManager.default
-            let tempDir = fileManager.temporaryDirectory
-            let fileName = url.lastPathComponent.isEmpty ? "attachment" : url.lastPathComponent
-            let destination = tempDir.appendingPathComponent(UUID().uuidString + "_" + fileName)
-            if fileManager.fileExists(atPath: destination.path) {
-                try fileManager.removeItem(at: destination)
-            }
-            try fileManager.copyItem(at: url, to: destination)
-            await MainActor.run {
-                viewModel.sendFileAttachment(from: destination)
-            }
-        } catch {
-            SecureLogger.error("File copy failed before send: \(error)", category: .session)
-        }
-    }
-
     func applicationFilesDirectory() -> URL? {
         // Cache the directory lookup to avoid repeated FileManager calls during view rendering
         struct Cache {

bitchat/Views/Media/FileAttachmentView.swift

@@ -1,118 +0,0 @@
-import SwiftUI
-
-struct FileAttachmentView: View {
-    private let url: URL
-    private let isSending: Bool
-    private let progress: Double?
-    private let onCancel: (() -> Void)?
-
-    @Environment(\.colorScheme) private var colorScheme
-    #if os(iOS)
-    @State private var showExporter = false
-    #endif
-
-    init(url: URL, isSending: Bool, progress: Double?, onCancel: (() -> Void)?) {
-        self.url = url
-        self.isSending = isSending
-        self.progress = progress
-        self.onCancel = onCancel
-    }
-
-    private var fileName: String {
-        url.lastPathComponent
-    }
-
-    private var normalizedProgress: Double? {
-        guard let progress = progress else { return nil }
-        return max(0, min(1, progress))
-    }
-
-    var body: some View {
-        HStack(alignment: .center, spacing: 12) {
-            Image(systemName: "doc.fill")
-                .foregroundColor(Color.blue)
-                .font(.bitchatSystem(size: 24))
-
-            VStack(alignment: .leading, spacing: 4) {
-                Text(fileName)
-                    .font(.bitchatSystem(size: 14, weight: .medium))
-                    .foregroundColor(.primary)
-                    .lineLimit(2)
-                Text(url.lastPathComponent)
-                    .font(.bitchatSystem(size: 11, design: .monospaced))
-                    .foregroundColor(.secondary)
-                    .lineLimit(1)
-                if let progress = normalizedProgress {
-                    ProgressView(value: progress)
-                        .progressViewStyle(.linear)
-                        .tint(Color.blue)
-                }
-            }
-
-            Spacer()
-
-            Button(action: openFile) {
-                Text("open", comment: "Button to open attached file")
-                    .font(.bitchatSystem(size: 13, weight: .semibold))
-                    .padding(.horizontal, 12)
-                    .padding(.vertical, 6)
-                    .background(
-                        Capsule().fill(Color.blue.opacity(0.15))
-                    )
-            }
-            .buttonStyle(.plain)
-
-            if let onCancel = onCancel, isSending {
-                Button(action: onCancel) {
-                    Image(systemName: "xmark")
-                        .font(.bitchatSystem(size: 11, weight: .bold))
-                        .frame(width: 26, height: 26)
-                        .background(Circle().fill(Color.red.opacity(0.9)))
-                        .foregroundColor(.white)
-                }
-                .buttonStyle(.plain)
-            }
-        }
-        .padding(12)
-        .background(
-            RoundedRectangle(cornerRadius: 14)
-                .fill(colorScheme == .dark ? Color.black.opacity(0.6) : Color.white)
-        )
-        .overlay(
-            RoundedRectangle(cornerRadius: 14)
-                .stroke(Color.gray.opacity(0.2), lineWidth: 1)
-        )
-        #if os(iOS)
-        .sheet(isPresented: $showExporter) {
-            FileExportController(url: url)
-        }
-        #endif
-    }
-
-    private func openFile() {
-        #if os(iOS)
-        showExporter = true
-        #else
-        NSWorkspace.shared.open(url)
-        #endif
-    }
-}
-
-#if os(iOS)
-import UniformTypeIdentifiers
-import UIKit
-
-private struct FileExportController: UIViewControllerRepresentable {
-    let url: URL
-
-    func makeUIViewController(context: Context) -> UIDocumentPickerViewController {
-        let controller = UIDocumentPickerViewController(forExporting: [url])
-        controller.shouldShowFileExtensions = true
-        return controller
-    }
-
-    func updateUIViewController(_ uiViewController: UIDocumentPickerViewController, context: Context) {}
-}
-#else
-import AppKit
-#endif