Updates code to replace mp4 downloads and use hls streams instead

Emitron/Emitron/AppDelegate.swift

@@ -76,7 +76,7 @@ class AppDelegate: UIResponder, UIApplicationDelegate {
       persistenceStore: persistenceStore,
       downloadService: downloadService
     )
-    downloadService.startProcessing()    
+    downloadService.startProcessing()
   }
 
   // MARK: UISceneSession Lifecycle

Emitron/Emitron/Data/ViewModels/VideoPlaybackViewModel.swift

@@ -380,7 +380,8 @@ private extension VideoPlaybackViewModel {
       if let download = state.download,
         download.state == .complete,
         let localURL = download.localURL {
-        let item = AVPlayerItem(url: localURL)
+        let asset = AVURLAsset(url: localURL)
+        let item = AVPlayerItem(asset: asset)
         self.addMetadata(from: state, to: item)
         self.addClosedCaptions(for: item)
         // Add it to the cache

Emitron/Emitron/Downloads/DownloadProcessor.swift

@@ -28,6 +28,7 @@
 
 import Foundation
 import Combine
+import AVFoundation
 
 protocol DownloadProcessorModel {
   var id: UUID { get }
@@ -56,6 +57,18 @@ private extension URLSessionDownloadTask {
   }
 }
 
+private extension AVAssetDownloadTask {
+  var downloadId: UUID? {
+    get {
+      guard let taskDescription = taskDescription else { return .none }
+      return UUID(uuidString: taskDescription)
+    }
+    set {
+      taskDescription = newValue?.uuidString ?? ""
+    }
+  }
+}
+
 enum DownloadProcessorError: Error {
   case invalidArguments
   case unknownDownload
@@ -64,17 +77,21 @@ enum DownloadProcessorError: Error {
 // Manage a list of files to download—either queued, in progresss, paused or failed.
 final class DownloadProcessor: NSObject {
   static let sessionIdentifier = "com.razeware.emitron.DownloadProcessor"
+  static let sdBitrate = 250_000
+  private var downloadQuality: Attachment.Kind {
+    SettingsManager.current.downloadQuality
+  }
 
-  private lazy var session: URLSession = {
+  private lazy var session: AVAssetDownloadURLSession = {
     let config = URLSessionConfiguration.background(withIdentifier: DownloadProcessor.sessionIdentifier)
     // Uncommenting this causes the download task to fail with POSIX 22. But seemingly only with
     // Vimeo URLs. So that's handy.
     // config.isDiscretionary = true
     config.sessionSendsLaunchEvents = true
-    return URLSession(configuration: config, delegate: self, delegateQueue: .none)
+    return AVAssetDownloadURLSession(configuration: config, assetDownloadDelegate: self, delegateQueue: .none)
   }()
   var backgroundSessionCompletionHandler: (() -> Void)?
-  private var currentDownloads = [URLSessionDownloadTask]()
+  private var currentDownloads = [AVAssetDownloadTask]()
   private var throttleList = [UUID: Double]()
   weak var delegate: DownloadProcessorDelegate!
 
@@ -87,8 +104,13 @@ final class DownloadProcessor: NSObject {
 extension DownloadProcessor {
   func add(download: DownloadProcessorModel) throws {
     guard let remoteURL = download.remoteURL else { throw DownloadProcessorError.invalidArguments }
-
-    let downloadTask = session.downloadTask(with: remoteURL)
+    let hlsAsset = AVURLAsset(url: remoteURL)
+    var options: [String: Any]?
+    if downloadQuality == .sdVideoFile {
+      options = [AVAssetDownloadTaskMinimumRequiredMediaBitrateKey: DownloadProcessor.sdBitrate]
+    }
+    guard let downloadTask = session.makeAssetDownloadTask(asset: hlsAsset, assetTitle: "\(download.id))", assetArtworkData: nil, options: options) else { return }
+
     downloadTask.downloadId = download.id
     downloadTask.resume()
 
@@ -117,13 +139,15 @@ extension DownloadProcessor {
 }
 
 extension DownloadProcessor {
-  private func getDownloadTasksFromSession() -> [URLSessionDownloadTask] {
-    var tasks = [URLSessionDownloadTask]()
+  private func getDownloadTasksFromSession() -> [AVAssetDownloadTask] {
+    var tasks = [AVAssetDownloadTask]()
     // Use a semaphore to make an async call synchronous
     // --There's no point in trying to complete instantiating this class without this list.
     let semaphore = DispatchSemaphore(value: 0)
-    session.getTasksWithCompletionHandler { _, _, downloadTasks in
-      tasks = downloadTasks
+    session.getAllTasks { downloadTasks in
+
+      let myTasks = downloadTasks as! [AVAssetDownloadTask]
+      tasks = myTasks
       semaphore.signal()
     }
 
@@ -137,6 +161,47 @@ extension DownloadProcessor {
   }
 }
 
+extension DownloadProcessor: AVAssetDownloadDelegate {
+
+  func urlSession(_ session: URLSession, assetDownloadTask: AVAssetDownloadTask, didLoad timeRange: CMTimeRange, totalTimeRangesLoaded loadedTimeRanges: [NSValue], timeRangeExpectedToLoad: CMTimeRange) {
+
+    guard let downloadId = assetDownloadTask.downloadId else { return }
+
+    var percentComplete = 0.0
+    for value in loadedTimeRanges {
+      let loadedTimeRange: CMTimeRange = value.timeRangeValue
+      percentComplete += CMTimeGetSeconds(loadedTimeRange.duration) / CMTimeGetSeconds(timeRangeExpectedToLoad.duration)
+    }
+
+    if let lastReportedProgress = throttleList[downloadId],
+      abs(percentComplete - lastReportedProgress) < 0.02 {
+      // Less than a 2% change—it's a no-op
+      return
+    }
+    throttleList[downloadId] = percentComplete
+    delegate.downloadProcessor(self, downloadWithId: downloadId, didUpdateProgress: percentComplete)
+  }
+
+  func urlSession(_ session: URLSession, assetDownloadTask: AVAssetDownloadTask, didFinishDownloadingTo location: URL) {
+
+    guard let downloadId = assetDownloadTask.downloadId,
+      let delegate = delegate else { return }
+
+    let download = delegate.downloadProcessor(self, downloadModelForDownloadWithId: downloadId)
+    guard let localURL = download?.localURL else { return }
+
+    let fileManager = FileManager.default
+    do {
+      if fileManager.fileExists(atPath: localURL.path) {
+        try fileManager.removeItem(at: localURL)
+      }
+      try fileManager.moveItem(at: location, to: localURL)
+    } catch {
+      delegate.downloadProcessor(self, downloadWithId: downloadId, didFailWithError: error)
+    }
+  }
+}
+
 extension DownloadProcessor: URLSessionDownloadDelegate {
   // When the background session has finished sending us events, we can tell the system we're done.
   func urlSessionDidFinishEvents(forBackgroundURLSession session: URLSession) {
@@ -181,44 +246,30 @@ extension DownloadProcessor: URLSessionDownloadDelegate {
 
   // Use this to handle and client-side download errors
   func urlSession(_ session: URLSession, task: URLSessionTask, didCompleteWithError error: Error?) {
-    guard let downloadTask = task as? URLSessionDownloadTask, let downloadId = downloadTask.downloadId else { return }
-
+
+    guard let downloadTask = task as? AVAssetDownloadTask, let downloadId = downloadTask.downloadId else { return }
+
     if let error = error as NSError? {
       let cancellationReason = (error.userInfo[NSURLErrorBackgroundTaskCancelledReasonKey] as? NSNumber)?.intValue
       if cancellationReason == NSURLErrorCancelledReasonUserForceQuitApplication || cancellationReason == NSURLErrorCancelledReasonBackgroundUpdatesDisabled {
         // The download was cancelled for technical reasons, but we might be able to restart it...
-        var newTask: URLSessionDownloadTask?
-        if let resumeData = error.userInfo[NSURLSessionDownloadTaskResumeData] as? Data {
-          newTask = session.downloadTask(withResumeData: resumeData)
-        } else {
-          let download = delegate.downloadProcessor(self, downloadModelForDownloadWithId: downloadId)
-          if let remoteURL = download?.remoteURL {
-            newTask = session.downloadTask(with: remoteURL)
-          }
-        }
-        if let newTask = newTask {
-          newTask.downloadId = downloadId
-          newTask.resume()
-          currentDownloads.append(newTask)
-          delegate.downloadProcessor(self, didStartDownloadWithId: downloadId)
-        }
-
+
         currentDownloads.removeAll { $0 == downloadTask }
       } else if error.code == NSURLErrorCancelled {
         // User-requested cancellation
         currentDownloads.removeAll { $0 == downloadTask }
-        
+
         delegate.downloadProcessor(self, didCancelDownloadWithId: downloadId)
       } else {
         // Unknown error
         currentDownloads.removeAll { $0 == downloadTask }
-        
+
         delegate.downloadProcessor(self, downloadWithId: downloadId, didFailWithError: error)
       }
     } else {
       // Success!
       currentDownloads.removeAll { $0 == downloadTask }
-      
+
       delegate.downloadProcessor(self, didFinishDownloadWithId: downloadId)
     }
   }

Emitron/Emitron/Downloads/DownloadService.swift

@@ -299,28 +299,28 @@ extension DownloadService {
     }
 
     // Use the video service to request the URLs
-    videosService.getVideoDownload(for: videoId) { [weak self] result in
+    videosService.getVideoStreamDownload(for: videoId) { [weak self] result in
       // Ensure we're still around
       guard let self = self else { return }
       var download = downloadQueueItem.download
-      
+
       switch result {
       case .failure(let error):
         Failure
           .downloadService(from: "requestDownloadURL",
                            reason: "Unable to obtain download URLs: \(error)")
           .log()
-      case .success(let attachments):
-        download.remoteURL = attachments.first { $0.kind == self.downloadQuality }?.url
+      case .success(let attachment):
+        download.remoteURL = attachment.url
         download.lastValidatedAt = Date()
         download.state = .readyForDownload
       }
-      
+
       // Update the state if required
       if download.remoteURL == nil {
         download.state = .error
       }
-      
+
       // Commit the changes
       do {
         try self.persistenceStore.update(download: download)
@@ -332,7 +332,6 @@ extension DownloadService {
         self.transitionDownload(withID: download.id, to: .failed)
       }
     }
-
     // Move it on through the state machine
     transitionDownload(withID: downloadQueueItem.download.id, to: .urlRequested)
   }
@@ -356,7 +355,7 @@ extension DownloadService {
     }
 
     // Generate filename
-    let filename = "\(videoId).mp4"
+    let filename = "\(videoId).m3u8"
 
     // Save local URL and filename
     var download = downloadQueueItem.download

Emitron/Emitron/Networking/Requests/VideosRequest.swift

@@ -56,23 +56,29 @@ struct StreamVideoRequest: Request {
   }
 }
 
-struct DownloadVideoRequest: Request {
-  // It contains two Attachment objects, one for the HD file and one for the SD file.
-  typealias Response = [Attachment]
+struct DownloadStreamVideoRequest: Request {
+  typealias Response = Attachment
 
   // MARK: - Properties
   var method: HTTPMethod { .GET }
-  var path: String { "/videos/\(id)/download" }
+  var path: String { "/videos/\(id)/stream" }
   var additionalHeaders: [String: String] = [:]
   var body: Data? { nil }
 
   // MARK: - Parameters
   let id: Int
 
   // MARK: - Internal
-  func handle(response: Data) throws -> [Attachment] {
+  func handle(response: Data) throws -> Attachment {
     let json = try JSON(data: response)
     let doc = JSONAPIDocument(json)
-    return try doc.data.map { try AttachmentAdapter.process(resource: $0) }
+    let attachments = try doc.data.map { try AttachmentAdapter.process(resource: $0) }
+
+    guard let attachment = attachments.first,
+      attachments.count == 1 else {
+        throw RWAPIError.responseHasIncorrectNumberOfElements
+    }
+
+    return attachment
   }
 }

Emitron/Emitron/Networking/Services/Service.swift

@@ -85,7 +85,6 @@ class Service {
   func prepare<R: Request>(request: R,
                            parameters: [Parameter]?) -> URLRequest? {
     let pathURL = networkClient.environment.baseURL.appendingPathComponent(request.path)
-
     var components = URLComponents(url: pathURL,
                                    resolvingAgainstBaseURL: false)
 

Emitron/Emitron/Networking/Services/VideosService.swift

@@ -37,9 +37,9 @@ class VideosService: Service {
                           completion: completion)
   }
 
-  func getVideoDownload(for id: Int,
-                        completion: @escaping (_ response: Result<DownloadVideoRequest.Response, RWAPIError>) -> Void) {
-    let request = DownloadVideoRequest(id: id)
+  func getVideoStreamDownload(for id: Int,
+                              completion: @escaping (_ response: Result<StreamVideoRequest.Response, RWAPIError>) -> Void) {
+    let request = DownloadStreamVideoRequest(id: id)
     makeAndProcessRequest(request: request,
                           completion: completion)
   }

Emitron/Emitron/Sessions/SessionController.swift

@@ -144,8 +144,6 @@ class SessionController: NSObject, UserModelController, ObservablePrePostFactoOb
               .log()
           case .success(let user):
             self.user = user
-            print(user)
-
             Event
               .login(from: "SessionController")
               .log()

Emitron/Emitron/UI/Shared/Content Detail/ChildContentListingView.swift

@@ -62,6 +62,11 @@ private extension ChildContentListingView {
               .kerning(-0.5)
               .foregroundColor(.titleText)
               .padding([.top, .bottom])
+            Button {
+              exit(0)
+            } label: {
+              Text("Close App0")
+            }
             Spacer()
           }.padding([.leading, .trailing], 20)
         }