Import: Support for importing a config file from file providers

Signed-off-by: Roopesh Chander <roop@roopc.net>

WireGuard/WireGuard/UI/iOS/FilePicker.swift

@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: MIT
+// Copyright © 2018 WireGuard LLC. All rights reserved.
+
+import UIKit
+
+class FileImportViewController: UIDocumentPickerViewController {
+    enum DocumentType: String {
+        case wgQuickConfigFile = "com.wireguard.config.quick"
+    }
+
+    init(documentTypes: [DocumentType]) {
+        super.init(documentTypes: documentTypes.map { $0.rawValue }, in: .import)
+    }
+
+    required init?(coder aDecoder: NSCoder) {
+        fatalError("init(coder:) has not been implemented")
+    }
+}

WireGuard/WireGuard/UI/iOS/TunnelsListTableViewController.swift

@@ -40,16 +40,21 @@ class TunnelsListTableViewController: UITableViewController {
         let alert = UIAlertController(title: "",
                                       message: "Add a tunnel",
                                       preferredStyle: .actionSheet)
-        alert.addAction(
-            UIAlertAction(title: "Create from scratch", style: .default) { [weak self] (action) in
-                if let s = self, let tunnelsManager = s.tunnelsManager {
-                    s.presentViewControllerForTunnelCreation(tunnelsManager: tunnelsManager, tunnelConfiguration: nil)
-                }
+        let importFileAction = UIAlertAction(title: "Import wg-quick config (.conf)", style: .default) { [weak self] (action) in
+            self?.presentViewControllerForFileImport()
+        }
+        alert.addAction(importFileAction)
+
+        let createFromScratchAction = UIAlertAction(title: "Create from scratch", style: .default) { [weak self] (action) in
+            if let s = self, let tunnelsManager = s.tunnelsManager {
+                s.presentViewControllerForTunnelCreation(tunnelsManager: tunnelsManager, tunnelConfiguration: nil)
             }
-        )
-        alert.addAction(
-            UIAlertAction(title: "Cancel", style: .cancel)
-        )
+        }
+        alert.addAction(createFromScratchAction)
+
+        let cancelAction = UIAlertAction(title: "Cancel", style: .cancel)
+        alert.addAction(cancelAction)
+
         // popoverPresentationController will be nil on iPhone and non-nil on iPad
         alert.popoverPresentationController?.barButtonItem = self.navigationItem.rightBarButtonItem
         self.present(alert, animated: true, completion: nil)
@@ -83,6 +88,12 @@ class TunnelsListTableViewController: UITableViewController {
         self.present(editNC, animated: true)
     }
 
+    func presentViewControllerForFileImport() {
+        let filePicker = FileImportViewController(documentTypes: [.wgQuickConfigFile])
+        filePicker.delegate = self
+        self.present(filePicker, animated: true)
+    }
+
     func showErrorAlert(title: String, message: String) {
         let okAction = UIAlertAction(title: "Ok", style: .default)
         let alert = UIAlertController(title: title, message: message, preferredStyle: .alert)
@@ -107,6 +118,16 @@ extension TunnelsListTableViewController: TunnelEditTableViewControllerDelegate
     }
 }
 
+// MARK: UIDocumentPickerDelegate
+
+extension TunnelsListTableViewController: UIDocumentPickerDelegate {
+    func documentPicker(_ controller: UIDocumentPickerViewController, didPickDocumentsAt urls: [URL]) {
+        if let url = urls.first {
+            openForEditing(configFileURL: url)
+        }
+    }
+}
+
 // MARK: UITableViewDataSource
 
 extension TunnelsListTableViewController {