From 6f268d7998fc926312280e1c83d076bd20a27af7 Mon Sep 17 00:00:00 2001
From: Peter <>
Date: Wed, 17 Jul 2019 17:45:23 +0100
Subject: [PATCH] More granular video scrubbing

---
 .../Sources/UniversalSoftwareVideoSource.swift     | 13 ++++++++-----
 submodules/Postbox/Postbox/MediaBox.swift          |  1 +
 .../TelegramCore/TelegramCore/MultipartFetch.swift | 14 +++++++++-----
 3 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/submodules/MediaPlayer/Sources/UniversalSoftwareVideoSource.swift b/submodules/MediaPlayer/Sources/UniversalSoftwareVideoSource.swift
index 9eefce0a6b..e2eb160c36 100644
--- a/submodules/MediaPlayer/Sources/UniversalSoftwareVideoSource.swift
+++ b/submodules/MediaPlayer/Sources/UniversalSoftwareVideoSource.swift
@@ -19,11 +19,18 @@ private func readPacketCallback(userData: UnsafeMutableRawPointer?, buffer: Unsa
     data = context.mediaBox.resourceData(context.fileReference.media.resource, size: context.size, in: requestRange, mode: .partial)
     let requiredDataIsNotLocallyAvailable = context.requiredDataIsNotLocallyAvailable
     var fetchedData: Data?
+    let fetchDisposable = MetaDisposable()
+    let isInitialized = context.videoStream != nil
+    let mediaBox = context.mediaBox
+    let reference = context.fileReference.resourceReference(context.fileReference.media.resource)
     let disposable = data.start(next: { data in
         if data.count == readCount {
             fetchedData = data
             semaphore.signal()
         } else {
+            if isInitialized {
+                fetchDisposable.set(fetchedMediaResource(mediaBox: mediaBox, reference: reference, ranges: [(requestRange, .maximum)]).start())
+            }
             requiredDataIsNotLocallyAvailable?()
         }
     })
@@ -32,15 +39,11 @@ private func readPacketCallback(userData: UnsafeMutableRawPointer?, buffer: Unsa
             semaphore.signal()
         }
     })
-    var fetchDisposable: Disposable?
-    if context.videoStream != nil {
-        fetchDisposable = fetchedMediaResource(mediaBox: context.mediaBox, reference: context.fileReference.resourceReference(context.fileReference.media.resource), ranges: [(requestRange, .elevated)]).start()
-    }
     semaphore.wait()
     
     disposable.dispose()
     cancelDisposable.dispose()
-    fetchDisposable?.dispose()
+    fetchDisposable.dispose()
     
     if let fetchedData = fetchedData {
         fetchedData.withUnsafeBytes { (bytes: UnsafePointer<UInt8>) -> Void in
diff --git a/submodules/Postbox/Postbox/MediaBox.swift b/submodules/Postbox/Postbox/MediaBox.swift
index 9cd04f3ef1..81a554f8f5 100644
--- a/submodules/Postbox/Postbox/MediaBox.swift
+++ b/submodules/Postbox/Postbox/MediaBox.swift
@@ -70,6 +70,7 @@ public protocol MediaResourceDataFetchCopyLocalItem {
 public enum MediaBoxFetchPriority: Int32 {
     case `default` = 0
     case elevated = 1
+    case maximum = 2
 }
 
 public enum MediaResourceDataFetchResult {
diff --git a/submodules/TelegramCore/TelegramCore/MultipartFetch.swift b/submodules/TelegramCore/TelegramCore/MultipartFetch.swift
index b09ae7d48b..544306a9b1 100644
--- a/submodules/TelegramCore/TelegramCore/MultipartFetch.swift
+++ b/submodules/TelegramCore/TelegramCore/MultipartFetch.swift
@@ -400,7 +400,7 @@ private enum MultipartFetchSource {
 private final class MultipartFetchManager {
     let parallelParts: Int
     let defaultPartSize = 128 * 1024
-    let partAlignment = 128 * 1024
+    let partAlignment = 4 * 1024
     
     var resource: TelegramMediaResource
     var resourceReference: MediaResourceReference?
@@ -571,15 +571,19 @@ private final class MultipartFetchManager {
         }
         
         while !intervalsToFetch.isEmpty && self.fetchingParts.count < self.parallelParts && !self.reuploadingToCdn && !self.revalidatingMediaReference {
-            var elevatedIndices: [Int] = []
+            
+            var indicesByPriority: [MediaBoxFetchPriority: [Int]] = [:]
             for i in 0 ..< intervalsToFetch.count {
-                if case .elevated = intervalsToFetch[i].1 {
-                    elevatedIndices.append(i)
+                if indicesByPriority[intervalsToFetch[i].1] == nil {
+                    indicesByPriority[intervalsToFetch[i].1] = []
                 }
+                indicesByPriority[intervalsToFetch[i].1]!.append(i)
             }
             
             let currentIntervalIndex: Int
-            if !elevatedIndices.isEmpty {
+            if let maxIndices = indicesByPriority[.maximum], !maxIndices.isEmpty {
+                currentIntervalIndex = maxIndices[self.nextFetchingPartId % maxIndices.count]
+            } else if let elevatedIndices = indicesByPriority[.elevated], !elevatedIndices.isEmpty {
                 currentIntervalIndex = elevatedIndices[self.nextFetchingPartId % elevatedIndices.count]
             } else {
                 currentIntervalIndex = self.nextFetchingPartId % intervalsToFetch.count