KCD/EnhancementListItemDownloader.swift

   1 //
   2 //  EnhancementListItemDownloader.swift
   3 //  KCD
   4 //
   5 //  Created by Hori,Masaki on 2017/12/22.
   6 //  Copyright © 2017年 Hori,Masaki. All rights reserved.
   7 //
   8
   9 import Foundation
  10
  11 final class EnhancementListItemDownloader: NSObject, URLSessionDownloadDelegate {
  12
  13     private let resourceName: String
  14     private let resourceExtension: String
  15
  16     init(name: String, extension ext: String) {
  17
  18         self.resourceName = name
  19         self.resourceExtension = ext
  20
  21         super.init()
  22
  23         plistDownloadQueue = OperationQueue()
  24         plistDownloadQueue.name = "StrengthenListViewControllerPlistDownloadQueue"
  25         plistDownloadQueue.maxConcurrentOperationCount = 1
  26         plistDownloadQueue.qualityOfService = .background
  27
  28         let configuration = URLSessionConfiguration.default
  29
  30         plistDownloadSession = URLSession(configuration: configuration,
  31                                           delegate: self,
  32                                           delegateQueue: plistDownloadQueue)
  33     }
  34
  35     private var plistDownloadSession: URLSession!
  36     private var plistDownloadQueue: OperationQueue!
  37     private var plistDownloadTask: URLSessionDownloadTask?
  38     private var finishOperation: (([EnhancementListItem]) -> Void)?
  39
  40     func download(completeHandler: @escaping ([EnhancementListItem]) -> Void) {
  41
  42         if let _ = plistDownloadTask { return }
  43
  44         guard let plistURL = URL(string: "http://git.osdn.jp/view?p=kcd/KCD.git;a=blob;f=KCD/\(resourceName).\(resourceExtension);hb=HEAD") else { return }
  45
  46         finishOperation = completeHandler
  47         plistDownloadTask = plistDownloadSession.downloadTask(with: plistURL)
  48         plistDownloadTask?.resume()
  49     }
  50
  51     func urlSession(_ session: URLSession, downloadTask: URLSessionDownloadTask, didFinishDownloadingTo location: URL) {
  52
  53         plistDownloadTask = nil
  54
  55         guard let data = try? Data(contentsOf: location, options: []) else { return }
  56         guard let list = NSKeyedUnarchiver.unarchiveObject(with: data as Data) as? [EnhancementListItem] else { return }
  57
  58         finishOperation?(list)
  59     }
  60
  61     func urlSession(_ session: URLSession, task: URLSessionTask, didCompleteWithError error: Error?) {
  62
  63         plistDownloadTask = nil
  64     }
  65 }