iOS/WolneLektury/Connection/DownloadManager.swift

   1 //
   2 //  DownloadManager.swift
   3 //  WolneLektury
   4 //
   5 //  Created by Pawel Dabrowski on 22/06/2018.
   6 //  Copyright © 2018 Fundacja Nowoczesna Polska. All rights reserved.
   7 //
   8
   9 import UIKit
  10 import MZDownloadManager
  11
  12 enum FileStatus{
  13     case notDownloaded
  14     case downloading
  15     case downloaded
  16 }
  17
  18 enum FileType{
  19     case ebook
  20     case audiobook
  21
  22     private var destinationPath: String{
  23         switch self {
  24         case .ebook:
  25             return Constants.ebookPath
  26         case .audiobook:
  27             return Constants.audiobookPath
  28         }
  29     }
  30
  31     func destinationPathWithSlug(bookSlug: String) -> String {
  32         return destinationPath + "/" + bookSlug + "/"
  33     }
  34
  35     func pathForFileName(filename: String, bookSlug: String) -> String{
  36         return self.destinationPathWithSlug(bookSlug: bookSlug) + filename
  37     }
  38 }
  39
  40 protocol DownloadManagerDelegate: class{
  41     func downloadManagerDownloadProgressChanged(model: MZDownloadModel, allProgress: Float, bookSlug: String)
  42     func downloadManagerDownloadFinished(model: MZDownloadModel, bookSlug: String)
  43     func downloadManagerDownloadFailed(model: MZDownloadModel, bookSlug: String)
  44 }
  45
  46 extension MZDownloadModel {
  47     func isAudiobook() -> Bool {
  48         return self.destinationPath.starts(with: Constants.audiobookPath)
  49     }
  50     func isEbook() -> Bool {
  51         return self.destinationPath.starts(with: Constants.ebookPath)
  52     }
  53
  54 }
  55
  56 class DownloadingAudiobook{
  57     var allUrlsCount: Float = 0
  58     var waitingToDownloadUrls: [String]
  59     var downloadedUrls: [String]
  60     var bookSlug: String
  61     init(bookDetailsModel: BookDetailsModel) {
  62
  63         waitingToDownloadUrls = [String]()
  64         downloadedUrls = [String]()
  65
  66         let audiobookUrls = bookDetailsModel.getAudiobookFilesUrls()
  67         bookSlug = bookDetailsModel.slug
  68         allUrlsCount = Float(audiobookUrls.count)
  69
  70         for url in audiobookUrls{
  71             if NSObject.audiobookExists(audioBookUrlString: url, bookSlug: bookSlug){
  72                 downloadedUrls.append(url)
  73             }
  74             else{
  75                 waitingToDownloadUrls.append(url)
  76             }
  77         }
  78     }
  79
  80     func getProgress() -> Float{
  81         let allCount = waitingToDownloadUrls.count + downloadedUrls.count
  82         if allCount > 0{
  83             if downloadedUrls.count > 0{
  84                 return Float(downloadedUrls.count) / Float(allCount)
  85             }
  86         }
  87         return 0.0
  88     }
  89 }
  90
  91 class DownloadManager: NSObject, MZDownloadManagerDelegate{
  92
  93     weak var delegate: DownloadManagerDelegate?
  94     var downloadingAudiobooks = [DownloadingAudiobook]()
  95
  96     //Shared instance of DownloadManager
  97     static let sharedInstance : DownloadManager = {
  98         return DownloadManager()
  99     }()
 100
 101
 102     lazy var downloadManager: MZDownloadManager = {
 103         [unowned self] in
 104         let sessionIdentifer: String = "com.moiseum.WolneLektury.BackgroundSession"
 105
 106         let appDelegate = UIApplication.shared.delegate as! AppDelegate
 107         var completion = appDelegate.backgroundSessionCompletionHandler
 108
 109         let downloadmanager = MZDownloadManager(session: sessionIdentifer, delegate: self, completion: completion)
 110         return downloadmanager
 111         }()
 112
 113     func checkEbookStatus(bookSlug: String) -> FileStatus{
 114         if getEbookProgress(bookSlug: bookSlug) != nil{
 115             return .downloading
 116         }
 117
 118         if ebookExists(bookSlug: bookSlug){
 119             return .downloaded
 120         }
 121
 122         return .notDownloaded
 123     }
 124
 125     func getDownloadingAudiobook(bookSlug: String) -> DownloadingAudiobook? {
 126         for downloadingAudiobook in downloadingAudiobooks {
 127             if downloadingAudiobook.bookSlug == bookSlug {
 128                 return downloadingAudiobook
 129             }
 130         }
 131         return nil
 132     }
 133
 134     func clearDownloadingAudiobookFromQueue(bookSlug: String){
 135
 136         var i = 0
 137         var found = false
 138         for downloadingAudiobook in downloadingAudiobooks {
 139             if downloadingAudiobook.bookSlug == bookSlug {
 140                 found = true
 141                 break
 142             }
 143
 144             i += 1
 145         }
 146         if found {
 147             downloadingAudiobooks.remove(at: i)
 148         }
 149
 150         if let index = downloadManager.downloadingArray.index(where: {$0.destinationPath == FileType.audiobook.destinationPathWithSlug(bookSlug: bookSlug)}) {
 151             downloadManager.cancelTaskAtIndex(index)
 152         }
 153     }
 154
 155     func checkAudiobookStatus(bookDetailsModel: BookDetailsModel) -> FileStatus{
 156
 157         guard bookDetailsModel.slug.count > 0 else { return .notDownloaded}
 158
 159         if getDownloadingAudiobook(bookSlug: bookDetailsModel.slug) != nil {
 160             return .downloading
 161         }
 162
 163         if bookDetailsModel.checkIfAllAudiobookFilesAreDownloaded() {
 164             return .downloaded
 165         }
 166
 167         return .notDownloaded
 168     }
 169
 170     func deleteEbook(bookSlug: String){
 171
 172         let fileType = FileType.ebook
 173
 174         if let index = downloadManager.downloadingArray.index(where: {$0.fileName == bookSlug && $0.destinationPath == fileType.destinationPathWithSlug(bookSlug: bookSlug)}) {
 175             downloadManager.cancelTaskAtIndex(index)
 176         }
 177         else {
 178             let path = fileType.destinationPathWithSlug(bookSlug: bookSlug)// pathForFileName(filename: bookSlug,bookSlug: bookSlug)
 179             if FileManager.default.fileExists(atPath: path) {
 180                 try! FileManager.default.removeItem(atPath: path)
 181             }
 182         }
 183         UserDefaults.standard.removeObject(forKey: bookSlug)
 184     }
 185
 186     func deleteAudiobook(bookSlug: String){
 187
 188         let fileType = FileType.audiobook
 189
 190         try? FileManager.default.removeItem(atPath: fileType.destinationPathWithSlug(bookSlug: bookSlug))
 191     }
 192
 193     func getEbookProgress(bookSlug: String) -> Float? {
 194         if let model = downloadManager.downloadingArray.first(where: {$0.fileName == bookSlug && $0.destinationPath == FileType.ebook.destinationPathWithSlug(bookSlug: bookSlug)}){
 195             return model.progress
 196         }
 197         return nil
 198     }
 199
 200     func getAudiobookProgress(bookDetailsModel: BookDetailsModel) -> Float? {
 201
 202         guard let downloadingAudiobook = getDownloadingAudiobook(bookSlug: bookDetailsModel.slug) else {return nil}
 203
 204         return downloadingAudiobook.getProgress()
 205     }
 206
 207     func downloadEbook(bookDetailsModel: BookDetailsModel) {
 208
 209         guard bookDetailsModel.epub.count > 0, bookDetailsModel.slug.count > 0 else {
 210             return
 211         }
 212
 213         downloadManager.addDownloadTask(bookDetailsModel.slug, fileURL: bookDetailsModel.epub, destinationPath: FileType.ebook.destinationPathWithSlug(bookSlug: bookDetailsModel.slug))
 214     }
 215
 216     func downloadAudiobooks(bookDetailsModel: BookDetailsModel) {
 217
 218         let bookSlug = bookDetailsModel.slug
 219         guard bookDetailsModel.getAudiobookFilesUrls().count > 0, bookSlug.count > 0 else {
 220             return
 221         }
 222
 223         if let downloadingAudiobook = getDownloadingAudiobook(bookSlug:bookSlug){
 224
 225             if let firstUrl = downloadingAudiobook.waitingToDownloadUrls.first{
 226                 addDownloadAudiobookTask(bookSlug: bookSlug, fileUrl: firstUrl)
 227                 return
 228             }
 229             else{
 230                 clearDownloadingAudiobookFromQueue(bookSlug: bookSlug)
 231             }
 232         }
 233
 234         let downloadingAudiobook = DownloadingAudiobook(bookDetailsModel: bookDetailsModel)
 235         if let firstUrl = downloadingAudiobook.waitingToDownloadUrls.first {
 236             downloadingAudiobooks.append(downloadingAudiobook)
 237             addDownloadAudiobookTask(bookSlug: bookSlug, fileUrl: firstUrl)
 238         }
 239     }
 240
 241     func addDownloadAudiobookTask(bookSlug: String, fileUrl: String){
 242         downloadManager.addDownloadTask((fileUrl as NSString).lastPathComponent, fileURL: fileUrl, destinationPath: FileType.audiobook.destinationPathWithSlug(bookSlug: bookSlug))
 243     }
 244
 245     func notifyDelegateThatProgressChanged(downloadModel: MZDownloadModel){
 246         guard let delegate = delegate else { return }
 247
 248         if downloadModel.isAudiobook(){
 249             for downloadAudiobook in downloadingAudiobooks {
 250                 if downloadAudiobook.waitingToDownloadUrls.index(of: downloadModel.fileURL) != nil {
 251                     delegate.downloadManagerDownloadProgressChanged(model: downloadModel, allProgress: downloadAudiobook.getProgress() + downloadModel.progress/downloadAudiobook.allUrlsCount, bookSlug: downloadAudiobook.bookSlug)
 252                     return
 253                 }
 254             }
 255         }
 256         delegate.downloadManagerDownloadProgressChanged(model: downloadModel, allProgress: downloadModel.progress, bookSlug: downloadModel.fileName)
 257     }
 258
 259     func downloadRequestStarted(_ downloadModel: MZDownloadModel, index: Int) {
 260
 261         notifyDelegateThatProgressChanged(downloadModel: downloadModel)
 262     }
 263
 264     func downloadRequestDidPopulatedInterruptedTasks(_ downloadModels: [MZDownloadModel]) {
 265     }
 266
 267     func downloadRequestDidUpdateProgress(_ downloadModel: MZDownloadModel, index: Int) {
 268         notifyDelegateThatProgressChanged(downloadModel: downloadModel)
 269     }
 270
 271     func downloadRequestDidPaused(_ downloadModel: MZDownloadModel, index: Int) {
 272     }
 273
 274     func downloadRequestDidResumed(_ downloadModel: MZDownloadModel, index: Int) {
 275     }
 276
 277     func downloadRequestCanceled(_ downloadModel: MZDownloadModel, index: Int) {
 278         if downloadModel.isAudiobook(){
 279             for downloadAudiobook in downloadingAudiobooks {
 280                 if downloadAudiobook.waitingToDownloadUrls.index(of: downloadModel.fileURL) != nil {
 281                     clearDownloadingAudiobookFromQueue(bookSlug: downloadAudiobook.bookSlug)
 282
 283                     delegate?.downloadManagerDownloadFailed(model: downloadModel, bookSlug:downloadAudiobook.bookSlug )
 284                     return
 285                 }
 286             }
 287         }
 288
 289         delegate?.downloadManagerDownloadFailed(model: downloadModel, bookSlug: downloadModel.fileName)
 290     }
 291
 292     func downloadRequestFinished(_ downloadModel: MZDownloadModel, index: Int) {
 293
 294         // audiobook
 295         if downloadModel.isAudiobook() {
 296             for downloadAudiobook in downloadingAudiobooks {
 297                 if let index = downloadAudiobook.waitingToDownloadUrls.index(of: downloadModel.fileURL) {
 298                     downloadAudiobook.waitingToDownloadUrls.remove(at: index)
 299                     downloadAudiobook.downloadedUrls.append(downloadModel.fileURL)
 300                     let slug = downloadAudiobook.bookSlug
 301                     // check if there is any waiting to download url, and start downloading
 302                     if let firstUrl = downloadAudiobook.waitingToDownloadUrls.first(where: {$0.count > 0}) {
 303                         addDownloadAudiobookTask(bookSlug: downloadAudiobook.bookSlug, fileUrl: firstUrl)
 304                     }
 305                     else { // otherwise, downloading is finished, notify delegates
 306                         clearDownloadingAudiobookFromQueue(bookSlug: slug)
 307                         delegate?.downloadManagerDownloadFinished(model: downloadModel, bookSlug: slug)
 308                     }
 309                 }
 310             }
 311         }
 312         else {//ebook
 313             delegate?.downloadManagerDownloadFinished(model: downloadModel, bookSlug: downloadModel.fileName)
 314         }
 315     }
 316
 317     func downloadRequestDidFailedWithError(_ error: NSError, downloadModel: MZDownloadModel, index: Int) {
 318         var bookSlug = downloadModel.fileName
 319         if downloadModel.isAudiobook() {
 320             for downloadAudiobook in downloadingAudiobooks {
 321                 if downloadAudiobook.waitingToDownloadUrls.index(of: downloadModel.fileURL) != nil {
 322                     bookSlug = downloadAudiobook.bookSlug
 323                     clearDownloadingAudiobookFromQueue(bookSlug: bookSlug ?? "")
 324                     continue
 325                 }
 326             }
 327         }
 328         delegate?.downloadManagerDownloadFailed(model: downloadModel, bookSlug: downloadModel.fileName)
 329     }
 330
 331     //Oppotunity to handle destination does not exists error
 332     //This delegate will be called on the session queue so handle it appropriately
 333     func downloadRequestDestinationDoestNotExists(_ downloadModel: MZDownloadModel, index: Int, location: URL) {
 334         let myDownloadPath = downloadModel.destinationPath
 335         if !FileManager.default.fileExists(atPath: myDownloadPath) {
 336             try! FileManager.default.createDirectory(atPath: myDownloadPath, withIntermediateDirectories: true, attributes: nil)
 337         }
 338         let filePath = myDownloadPath + "/" + downloadModel.fileName
 339         if FileManager.default.fileExists(atPath: filePath){
 340            try! FileManager.default.removeItem(atPath: filePath)
 341         }
 342         try! FileManager.default.moveItem(at: location, to: URL(fileURLWithPath: filePath))
 343     }
 344 }