[AltStore] Update AltStore itself from UpdatesViewController

AltStore/Model/App.swift

@@ -11,8 +11,13 @@ import CoreData
 
 import Roxas
 
+extension App
+{
+    static let altstoreAppID = "com.rileytestut.AltStore"
+}
+
 @objc(App)
-class App: NSManagedObject, Decodable
+class App: NSManagedObject, Decodable, Fetchable
 {
     /* Properties */
     @NSManaged private(set) var name: String
@@ -24,7 +29,7 @@ class App: NSManagedObject, Decodable
     @NSManaged private(set) var iconName: String
     @NSManaged private(set) var screenshotNames: [String]
     
-    @NSManaged private(set) var version: String
+    @NSManaged var version: String
     @NSManaged private(set) var versionDate: Date
     @NSManaged private(set) var versionDescription: String?
     
@@ -83,4 +88,20 @@ extension App
     {
         return NSFetchRequest<App>(entityName: "App")
     }
+    
+    class func makeAltStoreApp(in context: NSManagedObjectContext) -> App
+    {
+        let app = App(context: context)
+        app.name = "AltStore"
+        app.identifier = "com.rileytestut.AltStore"
+        app.developerName = "Riley Testut"
+        app.localizedDescription = "AltStore is an alternative App Store."
+        app.iconName = ""
+        app.screenshotNames = []
+        app.version = "1.0"
+        app.versionDate = Date()
+        app.downloadURL = URL(string: "http://rileytestut.com")!
+        
+        return app
+    }
 }

AltStore/Model/DatabaseManager.swift

@@ -33,9 +33,15 @@ public extension DatabaseManager
         self.persistentContainer.loadPersistentStores { (description, error) in
             guard error == nil else { return completionHandler(error!) }
             
-            self.isStarted = true
-            
-            completionHandler(error)
+            self.prepareDatabase() { (result) in
+                switch result
+                {
+                case .failure(let error): completionHandler(error)
+                case .success:
+                    self.isStarted = true
+                    completionHandler(nil)
+                }
+            }
         }
     }
     
@@ -94,3 +100,45 @@ extension DatabaseManager
         return activeTeam
     }
 }
+
+private extension DatabaseManager
+{
+    func prepareDatabase(completionHandler: @escaping (Result<Void, Error>) -> Void)
+    {
+        self.persistentContainer.performBackgroundTask { (context) in
+            let version = Bundle.main.object(forInfoDictionaryKey: "CFBundleShortVersionString") as? String ?? "1.0"
+            
+            let altStoreApp: App
+            
+            if let app = App.first(satisfying: NSPredicate(format: "%K == %@", #keyPath(App.identifier), App.altstoreAppID), in: context)
+            {
+                altStoreApp = app
+            }
+            else
+            {
+                altStoreApp = App.makeAltStoreApp(in: context)
+                altStoreApp.version = version
+            }
+            
+            if let installedApp = altStoreApp.installedApp
+            {
+                installedApp.version = version
+            }
+            else
+            {
+                let installedApp = InstalledApp(app: altStoreApp, bundleIdentifier: altStoreApp.identifier, expirationDate: Date(), context: context)
+                installedApp.version = version
+            }
+            
+            do
+            {
+                try context.save()
+                completionHandler(.success(()))
+            }
+            catch
+            {
+                completionHandler(.failure(error))
+            }
+        }
+    }
+}