From fd69ef04aea330810c2c5917df5dd623275e2e8a Mon Sep 17 00:00:00 2001
From: jahorton <jahorton@sil.org>
Date: Tue, 23 Jun 2020 12:33:13 +0700
Subject: [PATCH] refactor(ios/engine): download start notifications

---
 .../ResourceDownloadManager.swift             | 22 +++++++++++++++----
 .../ResourceDownloadQueue.swift               | 16 +++-----------
 2 files changed, 21 insertions(+), 17 deletions(-)

diff --git a/ios/engine/KMEI/KeymanEngine/Classes/Resource Management/ResourceDownloadManager.swift b/ios/engine/KMEI/KeymanEngine/Classes/Resource Management/ResourceDownloadManager.swift
index d076762588..2f9e1f271b 100644
--- a/ios/engine/KMEI/KeymanEngine/Classes/Resource Management/ResourceDownloadManager.swift	
+++ b/ios/engine/KMEI/KeymanEngine/Classes/Resource Management/ResourceDownloadManager.swift	
@@ -115,8 +115,9 @@ public class ResourceDownloadManager {
       let fontTask = DownloadTask<InstallableKeyboard>(do: request, for: nil, type: nil)
       batchTasks.append(fontTask)
     }
-    
-    let batch = DownloadBatch(do: batchTasks, as: activity, ofType: .keyboard, completionBlock: completionBlock)
+
+    let startHandler = { self.defaultKeyboardStartBlock(for: keyboard) }
+    let batch = DownloadBatch(do: batchTasks, as: activity, ofType: .keyboard, startBlock: startHandler, completionBlock: completionBlock)
     batchTasks.forEach { task in
       task.request.userInfo[Key.downloadBatch] = batch
       task.request.userInfo[Key.downloadTask] = task
@@ -125,6 +126,12 @@ public class ResourceDownloadManager {
     return batch
   }
 
+  internal func defaultKeyboardStartBlock(for keyboard: InstallableKeyboard) {
+    NotificationCenter.default.post(name: Notifications.keyboardDownloadStarted,
+                                        object: self,
+                                        value: [keyboard])
+  }
+
   /// Asynchronously fetches the .js file for the keyboard with given IDs.
   /// See `Notifications` for notification on success/failiure.
   /// - Parameters:
@@ -257,8 +264,9 @@ public class ResourceDownloadManager {
 
     let lexicalModelTask = DownloadTask(do: request, for: [lexicalModel], type: .lexicalModel)
     let batchTasks: [DownloadTask<InstallableLexicalModel>] = [ lexicalModelTask ]
-    
-    let batch = DownloadBatch(do: batchTasks, as: activity, ofType: .lexicalModel, completionBlock: completionBlock)
+
+    let startHandler = { self.defaultLexicalModelStartBlock(for: lexicalModel) }
+    let batch = DownloadBatch(do: batchTasks, as: activity, ofType: .lexicalModel, startBlock: startHandler, completionBlock: completionBlock)
     batchTasks.forEach { task in
       task.request.userInfo[Key.downloadBatch] = batch
       task.request.userInfo[Key.downloadTask] = task
@@ -266,6 +274,12 @@ public class ResourceDownloadManager {
     
     return batch
   }
+
+  internal func defaultLexicalModelStartBlock(for lexicalModel: InstallableLexicalModel) {
+    NotificationCenter.default.post(name: Notifications.lexicalModelDownloadStarted,
+                                        object: self,
+                                        value: [lexicalModel])
+  }
   
   // Can be called by the cloud keyboard downloader and utilized.
   
diff --git a/ios/engine/KMEI/KeymanEngine/Classes/Resource Management/ResourceDownloadQueue.swift b/ios/engine/KMEI/KeymanEngine/Classes/Resource Management/ResourceDownloadQueue.swift
index aebbecd45c..9d9fcf1795 100644
--- a/ios/engine/KMEI/KeymanEngine/Classes/Resource Management/ResourceDownloadQueue.swift	
+++ b/ios/engine/KMEI/KeymanEngine/Classes/Resource Management/ResourceDownloadQueue.swift	
@@ -100,6 +100,7 @@ class DownloadBatch<Resource: LanguageResource>: AnyDownloadBatch {
     self.downloadTasks = tasks
 
     self.errors = Array(repeating: nil, count: tasks.count)
+    self.startBlock = startBlock
     self.completionBlock = completionBlock
   }
 
@@ -546,19 +547,8 @@ class ResourceDownloadQueue: HTTPDownloadDelegate {
     // The extra check is there to filter out other potential request types in the future.
     let batch = request.userInfo[Key.downloadBatch] as! AnyDownloadBatch
 
-    if request.tag == 0 && batch.activity != .update {
-      let task = request.userInfo[Key.downloadTask] as! AnyDownloadTask
-      if task.type == .keyboard {
-        let task = task as! DownloadTask<InstallableKeyboard>
-        NotificationCenter.default.post(name: Notifications.keyboardDownloadStarted,
-                                        object: self,
-                                        value: task.resources!)
-      } else if task.type == .lexicalModel {
-        let task = task as! DownloadTask<InstallableLexicalModel>
-        NotificationCenter.default.post(name: Notifications.lexicalModelDownloadStarted,
-                                        object: self,
-                                        value: task.resources!)
-      }
+    if batch.activity != .update {
+      batch.startBlock?()
     }
   }