fix #5 camera video preview with settling and diagnostics

- Wait until the picker movie's file size stops changing before
  staging it, so a movie whose final bytes are still being flushed is
  never copied truncated (which produced drafts without a thumbnail
  and unplayable previews).
- Log the whole camera video path (pickup size, staging result,
  analyze outcome, thumbnail decode) under the video-preview os_log
  category for fast on-device diagnosis.
- Cover the video analysis pipeline with a simulator test that
  generates an HEVC QuickTime movie and asserts duration plus JPEG
  thumbnail, and guard the diagnostics in Scripts/verify.sh.

Luma.xcodeproj/project.pbxproj

@@ -58,6 +58,7 @@
 		2F44B4FDA9AF67EB24776A16 /* WatchViews.swift in Sources */ = {isa = PBXBuildFile; fileRef = C35158C37C26CA9ACB6C9FFB /* WatchViews.swift */; };
 		30BE19F459FDDAD640F66C68 /* MessageReplyFallback.swift in Sources */ = {isa = PBXBuildFile; fileRef = 6DDD7A997EF0AF7DA9C3478B /* MessageReplyFallback.swift */; };
 		3121293D13481C39489CBC8F /* AttachmentDraft.swift in Sources */ = {isa = PBXBuildFile; fileRef = C04D749B7CA93CB7C59127D6 /* AttachmentDraft.swift */; };
+		312B8D266C5BEC4F7B2F3276 /* MediaPreviewProcessorVideoTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 8E29E7B704EE71C5AC70008E /* MediaPreviewProcessorVideoTests.swift */; };
 		3245372B071227092B8594C0 /* AccountPreferences.swift in Sources */ = {isa = PBXBuildFile; fileRef = 235CA66C5DFB8B6F9472D0C3 /* AccountPreferences.swift */; };
 		32528D1AA72FB1B1A72389E9 /* MartinOMEMO in Frameworks */ = {isa = PBXBuildFile; productRef = 7A670E49149C9C7E13F0A6A2 /* MartinOMEMO */; };
 		32790D95A577DCE99937B539 /* AccountPreferences.swift in Sources */ = {isa = PBXBuildFile; fileRef = 235CA66C5DFB8B6F9472D0C3 /* AccountPreferences.swift */; };
@@ -349,6 +350,7 @@
 		83A5787450609B0C14093679 /* WatchSessionModel.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = WatchSessionModel.swift; sourceTree = "<group>"; };
 		876CDF98063A4C948B00C7CE /* DeviceResource.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = DeviceResource.swift; sourceTree = "<group>"; };
 		8D2294F0FE44B2268A0620BB /* PhotoAttachmentPreview.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = PhotoAttachmentPreview.swift; sourceTree = "<group>"; };
+		8E29E7B704EE71C5AC70008E /* MediaPreviewProcessorVideoTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MediaPreviewProcessorVideoTests.swift; sourceTree = "<group>"; };
 		8F8DE3CE0E26DEA21A27CF67 /* LumaConnectionStatsModule.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = LumaConnectionStatsModule.swift; sourceTree = "<group>"; };
 		96829BDC257FD8D61083DA4D /* VideoNoteRecordingLifecycle.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = VideoNoteRecordingLifecycle.swift; sourceTree = "<group>"; };
 		99BE34DC082D19007241AA62 /* NewGroupView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = NewGroupView.swift; sourceTree = "<group>"; };
@@ -558,6 +560,7 @@
 				772A4F24CAF527E328657749 /* MediaFileIOTests.swift */,
 				A127BF01F5C488CD3E053379 /* MediaMetadataTests.swift */,
 				B38702A403DA3E943525FB62 /* MediaPickerSelectionPolicyTests.swift */,
+				8E29E7B704EE71C5AC70008E /* MediaPreviewProcessorVideoTests.swift */,
 				247FBE680C61D12AFB583862 /* MediaSendActivityTrackerTests.swift */,
 				76FEB73D4B67CB98C93F6244 /* MediaTimeFormatterTests.swift */,
 				6DCB924748780145A707D890 /* MediaViewerDismissGestureTests.swift */,
@@ -1081,6 +1084,7 @@
 				DC4FAE63AB8AF89C30512763 /* MediaFileIOTests.swift in Sources */,
 				10C5382981A87A2963DD397C /* MediaMetadataTests.swift in Sources */,
 				958FD3CBEC600651E1171B55 /* MediaPickerSelectionPolicyTests.swift in Sources */,
+				312B8D266C5BEC4F7B2F3276 /* MediaPreviewProcessorVideoTests.swift in Sources */,
 				4B2CFA4008D1234DCE35ADDE /* MediaSendActivityTrackerTests.swift in Sources */,
 				F27ACACEF60AFAB5AF96EF98 /* MediaTimeFormatterTests.swift in Sources */,
 				AC242F69C28F69A001D6559D /* MediaViewerDismissGestureTests.swift in Sources */,

Scripts/verify.sh

@@ -83,6 +83,7 @@ required=(
   Tests/ArchiveStoreTests.swift
   Tests/SASLprepTests.swift
   Tests/SaslFailureMessageTests.swift
+  Tests/MediaPreviewProcessorVideoTests.swift
   Sources/Shared/XMPP/SASLprep.swift
   Sources/Shared/XMPP/LumaSaslFailureModule.swift
   Sources/Shared/XMPP/SaslFailureMessage.swift
@@ -348,6 +349,10 @@ grep -q 'moveItem(at: sourceURL' Sources/Shared/UI/SystemPhotoCameraView.swift |
   echo "The picker movie must be claimed synchronously before dismissal cleanup"
   exit 1
 }
+grep -q 'video-preview' Sources/Shared/UI/ChatView.swift || {
+  echo "The camera video path must log diagnostics"
+  exit 1
+}
 grep -q 'ArchiveSyncCursorPolicy.requestPosition' Sources/Shared/XMPP/XMPPService.swift || {
   echo "MAM reconnects must prefer the durable archive UID over timestamps"
   exit 1

Sources/Shared/Services/MediaPreviewProcessor.swift

@@ -1,6 +1,7 @@
 import AVFoundation
 import Foundation
 import ImageIO
+import os
 import UniformTypeIdentifiers
 
 actor MediaPreviewProcessor {
@@ -44,6 +45,12 @@ actor MediaPreviewProcessor {
         }
 
         let waveform = kind == .voice ? voiceWaveform(for: url) : nil
+        if kind == .video {
+            let logger = Logger(subsystem: "Luma", category: "video-preview")
+            logger.info(
+                "analyze video: \(url.lastPathComponent) duration=\(String(describing: duration)) thumbnailBytes=\(thumbnailData?.count ?? 0)"
+            )
+        }
         return Analysis(
             duration: duration,
             thumbnailData: thumbnailData,
@@ -94,6 +101,8 @@ actor MediaPreviewProcessor {
                     return data
                 }
             } catch {
+                Logger(subsystem: "Luma", category: "video-preview")
+                    .error("image generator failed at \(second)s: \(error.localizedDescription)")
                 continue
             }
         }

Sources/Shared/UI/AttachmentPreviewView.swift

@@ -1,4 +1,5 @@
 import Foundation
+import os
 import SwiftUI
 
 #if os(iOS)
@@ -239,7 +240,13 @@ struct AttachmentPreviewView: View {
         thumbnailImages = thumbnailImages.filter { retainedIDs.contains($0.key) }
         for draft in drafts where thumbnailImages[draft.id] == nil {
             guard let data = draft.thumbnailData,
-                  let image = DraftThumbnailImage(data: data) else { continue }
+                  let image = DraftThumbnailImage(data: data) else {
+                if draft.kind == .video {
+                    Logger(subsystem: "Luma", category: "video-preview")
+                        .warning("video draft has no decodable thumbnail: \(draft.filename) thumbnailBytes=\(draft.thumbnailData?.count ?? 0)")
+                }
+                continue
+            }
             thumbnailImages[draft.id] = image
             await Task.yield()
         }

Sources/Shared/UI/ChatView.swift

@@ -1,6 +1,7 @@
 import CoreTransferable
 import Foundation
 import ImageIO
+import os
 import PhotosUI
 import SwiftData
 import SwiftUI
@@ -1263,12 +1264,44 @@ struct ChatView: View {
             photoCameraIsPreparingResult = false
             releaseArchiveSyncAfterCapture()
         }
+        let logger = Logger(subsystem: "Luma", category: "video-preview")
+        await waitForCameraFileSettling(at: media.url, logger: logger)
         let staged = await stageImportedFiles([media.url], preferredKind: media.kind)
-        if !staged, model.errorMessage == nil {
+        if staged {
-            model.errorMessage = "Камера вернула файл, который не удалось подготовить к отправке."
+            if let draft = attachmentDrafts.last {
+                logger.info(
+                    "camera draft staged: kind=\(draft.kind.rawValue) mime=\(draft.mimeType) size=\(draft.byteCount) duration=\(String(describing: draft.duration)) thumbnailBytes=\(draft.thumbnailData?.count ?? 0)"
+                )
+            }
+        } else {
+            logger.error("camera staging produced no drafts")
+            if model.errorMessage == nil {
+                model.errorMessage = "Камера вернула файл, который не удалось подготовить к отправке."
+            }
         }
     }
 
+    /// The picker can hand over a movie whose final bytes are still being
+    /// flushed. Wait until the file size stops changing so staging never
+    /// copies a truncated file.
+    private func waitForCameraFileSettling(at url: URL, logger: Logger) async {
+        guard let initial = try? url.resourceValues(forKeys: [.fileSizeKey]).fileSize else {
+            return
+        }
+        var previous = initial
+        for _ in 0..<10 {
+            try? await Task.sleep(nanoseconds: 250_000_000)
+            guard let current = try? url.resourceValues(forKeys: [.fileSizeKey]).fileSize else {
+                return
+            }
+            if current == previous {
+                return
+            }
+            previous = current
+        }
+        logger.warning("camera file size kept changing; staging anyway")
+    }
+
     private func presentCamera() {
         #if os(iOS)
             guard SystemPhotoCameraView.isAvailable else {

Sources/Shared/UI/SystemPhotoCameraView.swift

@@ -1,4 +1,5 @@
 import Foundation
+import os
 
 struct CapturedCameraMedia: Sendable {
     let url: URL
@@ -121,7 +122,10 @@ struct SystemPhotoCameraView: UIViewControllerRepresentable {
         /// races that cleanup and fails with an unreadable source. The move
         /// is a same-volume rename and does not block the main thread.
         private func prepareMovie(from sourceURL: URL) {
+            let logger = Logger(subsystem: "Luma", category: "video-preview")
             do {
+                let sourceSize = (try? sourceURL.resourceValues(forKeys: [.fileSizeKey]).fileSize) ?? -1
+                logger.info("picker movie ready: source=\(sourceURL.lastPathComponent) size=\(sourceSize)")
                 let fileExtension = sourceURL.pathExtension.isEmpty
                     ? "mov"
                     : sourceURL.pathExtension
@@ -130,13 +134,15 @@ struct SystemPhotoCameraView: UIViewControllerRepresentable {
                 let values = try destination.resourceValues(
                     forKeys: [.fileSizeKey, .isRegularFileKey]
                 )
-                guard values.isRegularFile == true,
+                let movedSize = values.fileSize ?? 0
-                      (values.fileSize ?? 0) > 0 else {
+                logger.info("picker movie moved: size=\(movedSize) regular=\(values.isRegularFile == true)")
+                guard values.isRegularFile == true, movedSize > 0 else {
                     try? FileManager.default.removeItem(at: destination)
                     throw SystemCameraError.emptyMovie
                 }
                 onMedia(.success(CapturedCameraMedia(url: destination, kind: .video)))
             } catch {
+                logger.error("picker movie preparation failed: \(error.localizedDescription)")
                 onMedia(.failure(error))
             }
         }

Tests/MediaPreviewProcessorVideoTests.swift

@@ -0,0 +1,68 @@
+import AVFoundation
+import XCTest
+@testable import Luma
+
+final class MediaPreviewProcessorVideoTests: XCTestCase {
+    /// Reproduces the camera-video analysis on the simulator: the pipeline
+    /// must produce a duration and a JPEG thumbnail for a freshly written
+    /// HEVC QuickTime movie.
+    func testVideoAnalysisProducesDurationAndThumbnail() async throws {
+        let url = try await Self.makeTestMovie()
+        defer { try? FileManager.default.removeItem(at: url) }
+
+        let processor = MediaPreviewProcessor()
+        let analysis = await processor.analyze(
+            url: url,
+            kind: .video,
+            mimeType: "video/quicktime"
+        )
+        XCTAssertNotNil(analysis.duration)
+        if let duration = analysis.duration {
+            XCTAssertGreaterThan(duration, 0)
+        }
+        XCTAssertNotNil(analysis.thumbnailData)
+        XCTAssertFalse(analysis.thumbnailData?.isEmpty ?? true)
+    }
+
+    private static func makeTestMovie() async throws -> URL {
+        let output = FileManager.default.temporaryDirectory
+            .appendingPathComponent("test-camera-\(UUID().uuidString).mov")
+        let writer = try AVAssetWriter(outputURL: output, fileType: .mov)
+        let input = AVAssetWriterInput(
+            mediaType: .video,
+            outputSettings: [
+                AVVideoCodecKey: AVVideoCodecType.hevc,
+                AVVideoWidthKey: 640,
+                AVVideoHeightKey: 480,
+            ]
+        )
+        input.expectsMediaDataInRealTime = true
+        let adaptor = AVAssetWriterInputPixelBufferAdaptor(
+            assetWriterInput: input,
+            sourcePixelBufferAttributes: [
+                kCVPixelBufferPixelFormatTypeKey as String: kCVPixelFormatType_32BGRA,
+                kCVPixelBufferWidthKey as String: 640,
+                kCVPixelBufferHeightKey as String: 480,
+            ]
+        )
+        writer.add(input)
+        guard writer.startWriting() else {
+            throw writer.error ?? NSError(domain: "test", code: 1)
+        }
+        writer.startSession(atSourceTime: .zero)
+        for frame in 0..<60 {
+            while !input.isReadyForMoreMediaData {
+                try await Task.sleep(nanoseconds: 2_000_000)
+            }
+            var buffer: CVPixelBuffer?
+            CVPixelBufferCreate(
+                kCFAllocatorDefault, 640, 480, kCVPixelFormatType_32BGRA, nil, &buffer
+            )
+            adaptor.append(buffer!, withPresentationTime: CMTime(value: Int64(frame), timescale: 30))
+        }
+        input.markAsFinished()
+        await writer.finishWriting()
+        return output
+    }
+}
+