Randomized pieces to download

BitTorrent.xcodeproj/project.pbxproj

@@ -10,6 +10,7 @@
 		0434EAB818A3C318E433338A /* Pods_BitTorrentTests.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = A8680B0EA21B5A20E03DEE6D /* Pods_BitTorrentTests.framework */; };
 		34D4082D0E0A2C899857DC89 /* Pods_BitTorrent.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 8B47AE52A67ECE61259FCDAD /* Pods_BitTorrent.framework */; };
 		867491B4C409A91D4D72CCE7 /* Pods_BitTorrent_BitTorrentExample.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = D97F9FB9F74204574FF6840B /* Pods_BitTorrent_BitTorrentExample.framework */; };
+		B501A5581F557E9E00B87911 /* RandomEnumeration.swift in Sources */ = {isa = PBXBuildFile; fileRef = B501A5571F557E9E00B87911 /* RandomEnumeration.swift */; };
 		B50B24F71F0A553F00C23E7C /* UDPConnectionTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = B50B24F61F0A553B00C23E7C /* UDPConnectionTests.swift */; };
 		B50B24F91F0A554A00C23E7C /* UDPConnection.swift in Sources */ = {isa = PBXBuildFile; fileRef = B50B24F81F0A554A00C23E7C /* UDPConnection.swift */; };
 		B514DD7B1F40971D00C932F8 /* TorrentViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = B514DD7A1F40971D00C932F8 /* TorrentViewController.swift */; };
@@ -168,6 +169,7 @@
 		8B47AE52A67ECE61259FCDAD /* Pods_BitTorrent.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = Pods_BitTorrent.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		99A91AD4708288B297A8B700 /* Pods-BitTorrentTests.debug.xcconfig */ = {isa = PBXFileReference; includeInIndex = 1; lastKnownFileType = text.xcconfig; name = "Pods-BitTorrentTests.debug.xcconfig"; path = "Pods/Target Support Files/Pods-BitTorrentTests/Pods-BitTorrentTests.debug.xcconfig"; sourceTree = "<group>"; };
 		A8680B0EA21B5A20E03DEE6D /* Pods_BitTorrentTests.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = Pods_BitTorrentTests.framework; sourceTree = BUILT_PRODUCTS_DIR; };
+		B501A5571F557E9E00B87911 /* RandomEnumeration.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = RandomEnumeration.swift; sourceTree = "<group>"; };
 		B50B24F61F0A553B00C23E7C /* UDPConnectionTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = UDPConnectionTests.swift; sourceTree = "<group>"; };
 		B50B24F81F0A554A00C23E7C /* UDPConnection.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = UDPConnection.swift; sourceTree = "<group>"; };
 		B514DD7A1F40971D00C932F8 /* TorrentViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = TorrentViewController.swift; sourceTree = "<group>"; };
@@ -407,6 +409,7 @@
 				B514DDA31F40E96100C932F8 /* CombinedNetworkSpeedTracker.swift */,
 				B514DD8E1F40C53C00C932F8 /* NetworkSpeedTrackerTests.swift */,
 				B514DD9B1F40DD1B00C932F8 /* URL.swift */,
+				B501A5571F557E9E00B87911 /* RandomEnumeration.swift */,
 			);
 			path = Utilities;
 			sourceTree = "<group>";
@@ -982,6 +985,7 @@
 				B558F4831F0A647D00438BB4 /* InternetProtocol.swift in Sources */,
 				B527F62B1F1BD5FA001F06AF /* TorrentPieceDownloadBuffer.swift in Sources */,
 				B5BFD9CC1F3FAF9A00CE0186 /* TorrentTrackerManager.swift in Sources */,
+				B501A5581F557E9E00B87911 /* RandomEnumeration.swift in Sources */,
 				B54D0C7A1CA69FAD004343BD /* TorrentMetaInfo.swift in Sources */,
 				B5C06F131F12CDD8005730B3 /* TorrentPeer.swift in Sources */,
 				B5F81E4B1F04399800B25C70 /* TorrentTrackerResponse.swift in Sources */,

BitTorrent/Models/BitField.swift

@@ -92,15 +92,24 @@ public struct BitField: Equatable {
     }
 }
 
-extension BitField: Sequence {
+extension BitField: Collection {
-    public func makeIterator() -> AnyIterator<(index: Int, isSet: Bool)> {
+    
-        var index = 0
+    public typealias Index = Array<Bool>.Index
-        return AnyIterator {
+    
-            guard index < self.size else { return nil }
+    public var startIndex: Index {
-            defer {
+        return value.startIndex
-                index += 1
+    }
-            }
+    
-            return (index, self.isSet(at: index))
+    public var endIndex: Index {
-        }
+        return value.endIndex
+    }
+    
+    public subscript(position: Index) -> (index: Int, isSet: Bool) {
+        precondition(indices.contains(position), "out of bounds")
+        return (index: position, isSet: value[position])
+    }
+    
+    public func index(after i: Index) -> Index {
+        return value.index(after: i)
     }
 }

BitTorrent/Peer/Piece Download Buffer/TorrentPieceDownloadBuffer.swift

@@ -73,6 +73,4 @@ class TorrentPieceDownloadBuffer {
         
         pendingRequests.remove(at: pendingIndex)
     }
-    
-    
 }

BitTorrent/Progress Manager/TorrentProgressManager.swift

@@ -43,7 +43,7 @@ class TorrentProgressManager {
     }
     
     func getNextPieceToDownload(from availablePieces: BitField) -> TorrentPieceRequest? {
-        for (i, isSet) in availablePieces where isSet {
+        for (i, isSet) in availablePieces.pseudoRandomized where isSet {
             if !progress.hasPiece(i) && !progress.isCurrentlyDownloading(piece: i) {
                 progress.setCurrentlyDownloading(piece: i)
                 return (i, metaInfo.info.lengthOfPiece(at: i), metaInfo.info.pieces[i])

BitTorrent/TCP Networking/GCDAsyncSocketStub.swift

@@ -12,10 +12,10 @@ import CocoaAsyncSocket
 class GCDAsyncSocketStub: GCDAsyncSocket {
     
     var connectToHostCalled = false
-    var connectToHostParameters: (host: String, port: UInt16)?
+    var connectToHostParameters: (host: String, port: UInt16, timeout: TimeInterval)?
-    override func connect(toHost host: String, onPort port: UInt16) throws {
+    override func connect(toHost host: String, onPort port: UInt16, withTimeout timeout: TimeInterval) throws {
         connectToHostCalled = true
-        connectToHostParameters = (host, port)
+        connectToHostParameters = (host, port, timeout)
     }
     
     var readDataCalled = false

BitTorrent/TCP Networking/TCPConnection.swift

@@ -61,7 +61,7 @@ class TCPConnection: NSObject, TCPConnectionProtocol {
     }
     
     func connect(to host: String, onPort port: UInt16) throws {
-        try socket.connect(toHost: host, onPort: port)
+        try socket.connect(toHost: host, onPort: port, withTimeout: 15)
     }
     
     func disconnect() {

BitTorrent/Utilities/RandomEnumeration.swift

@@ -0,0 +1,38 @@
+//
+//  RandomEnumeration.swift
+//  BitTorrent
+//
+//  Created by Ben Davis on 29/08/2017.
+//  Copyright © 2017 Ben Davis. All rights reserved.
+//
+
+import Foundation
+
+struct PseudoRandomizedSequence<Col, Elem>: Sequence
+    where Col: Collection, Col.Element == Elem, Col.Index == Int, Col.IndexDistance == Int {
+    
+    fileprivate let orderedSequence: Col
+    
+    func makeIterator() -> AnyIterator<Elem> {
+        
+        let length = orderedSequence.count
+        let seed = Int(arc4random()) % length
+        let increment = 13 // prime as the step
+        
+        var generatedNumber = seed
+        var count = 0
+        
+        return AnyIterator {
+            guard count != length else { return nil }
+            count += 1
+            generatedNumber = (generatedNumber + increment) % length
+            return self.orderedSequence[generatedNumber]
+        }
+    }
+}
+
+extension Collection where Index == Int, IndexDistance == Int {
+    var pseudoRandomized: PseudoRandomizedSequence<Self, Element> {
+        return PseudoRandomizedSequence(orderedSequence: self)
+    }
+}

BitTorrentExample/TorrentInfoRowData.swift

@@ -42,6 +42,7 @@ enum TorrentInfoRowData: Int {
     func value(using client: TorrentClient) -> String {
         
         let speedSampleSize: TimeInterval = 5
+        let etaSampleSize: TimeInterval = 30
         
         switch self {
             
@@ -73,8 +74,8 @@ enum TorrentInfoRowData: Int {
             return "????"
             
         case .eta:
-            let speed = client.downloadSpeedTracker.numberOfBytesDownloaded(over: speedSampleSize)
+            let speed = client.downloadSpeedTracker.numberOfBytesDownloaded(over: etaSampleSize)
-            let speedPerSecond = Double(speed) / speedSampleSize
+            let speedPerSecond = Double(speed) / etaSampleSize
             guard speed > 0 else { return "∞" }
             
             let remaining = client.progress.remaining * client.metaInfo.info.pieceLength

BitTorrentExample/TorrentViewController.swift

@@ -92,10 +92,10 @@ extension TorrentViewController: UITableViewDataSource {
                 return startCell
             } else {
                 let reCheckCell = UITableViewCell(style: .default, reuseIdentifier: nil)
-                startCell.textLabel?.text = "Start"
+                reCheckCell.textLabel?.text = "Start"
-                startCell.textLabel?.textAlignment = .center
+                reCheckCell.textLabel?.textAlignment = .center
-                startCell.textLabel?.textColor = .blue
+                reCheckCell.textLabel?.textColor = .blue
-                return startCell
+                return reCheckCell
             }
         }
     }