[AltStore] Adds LaunchViewController to async load database before UI appears

AltStore/LaunchViewController.swift

@@ -0,0 +1,51 @@
+//
+//  LaunchViewController.swift
+//  AltStore
+//
+//  Created by Riley Testut on 7/30/19.
+//  Copyright © 2019 Riley Testut. All rights reserved.
+//
+
+import UIKit
+import Roxas
+
+class LaunchViewController: RSTLaunchViewController
+{
+    override var launchConditions: [RSTLaunchCondition] {
+        let isDatabaseStarted = RSTLaunchCondition(condition: { DatabaseManager.shared.isStarted }) { (completionHandler) in
+            DatabaseManager.shared.start(completionHandler: completionHandler)
+        }
+
+        return [isDatabaseStarted]
+    }
+}
+
+extension LaunchViewController
+{
+    override func handleLaunchError(_ error: Error)
+    {
+        do
+        {
+            throw error
+        }
+        catch let error as NSError
+        {
+            let title = error.userInfo[NSLocalizedFailureErrorKey] as? String ?? NSLocalizedString("Unable to Launch AltStore", comment: "")
+            
+            let alertController = UIAlertController(title: title, message: error.localizedDescription, preferredStyle: .alert)
+            alertController.addAction(UIAlertAction(title: NSLocalizedString("Retry", comment: ""), style: .default, handler: { (action) in
+                self.handleLaunchConditions()
+            }))
+            self.present(alertController, animated: true, completion: nil)
+        }
+    }
+    
+    override func finishLaunching()
+    {
+        super.finishLaunching()
+        
+        AppManager.shared.update()
+        
+        self.performSegue(withIdentifier: "finishLaunching", sender: nil)
+    }
+}