show detailed error and instructions when location access is not granted

deltachat-ios/Chat/ChatViewController.swift

@@ -1647,7 +1647,16 @@ class ChatViewController: UITableViewController, UITableViewDropDelegate {
         guard let appDelegate = UIApplication.shared.delegate as? AppDelegate else {
             return
         }
-        appDelegate.locationManager.shareLocation(chatId: self.chatId, duration: seconds)
+        if !appDelegate.locationManager.shareLocation(chatId: self.chatId, duration: seconds) {
+            let alert = UIAlertController(title: String.localized("location_denied"), message: String.localized("location_denied_explain_ios"), preferredStyle: .alert)
+            if let appSettings = URL(string: UIApplication.openSettingsURLString) {
+                alert.addAction(UIAlertAction(title: String.localized("open_settings"), style: .default, handler: { _ in
+                        UIApplication.shared.open(appSettings, options: [:], completionHandler: nil)
+                }))
+            }
+            alert.addAction(UIAlertAction(title: String.localized("cancel"), style: .cancel, handler: nil))
+            navigationController?.present(alert, animated: true, completion: nil)
+        }
     }
 
     func updateMessage(_ msg: DcMsg) {

deltachat-ios/Helper/LocationManager.swift

@@ -29,7 +29,7 @@ class LocationManager: NSObject, CLLocationManagerDelegate {
         dcContext = dcAccounts.getSelected()
     }
 
-    func shareLocation(chatId: Int, duration: Int) {
+    func shareLocation(chatId: Int, duration: Int) -> Bool {
         if duration > 0 {
             var authStatus: CLAuthorizationStatus
             if #available(iOS 14.0, *) {
@@ -43,18 +43,21 @@ class LocationManager: NSObject, CLLocationManagerDelegate {
                 chatIdLocationRequest = chatId
                 durationLocationRequest = duration
                 locationManager.requestAlwaysAuthorization()
+                return true
             case .authorizedAlways, .authorizedWhenInUse:
                 dcContext.sendLocationsToChat(chatId: chatId, seconds: duration)
                 locationManager.startUpdatingLocation()
-            default:
-                // TODO: show an alert to inform the user why nothing works :)
-                logger.info("Location permission was rejected.")
+                return true
+            case .restricted, .denied:
+                logger.error("Location permission rejected: \(authStatus)")
+                return false
             }
         } else {
             dcContext.sendLocationsToChat(chatId: chatId, seconds: duration)
             if !dcContext.isSendingLocationsToChat(chatId: 0) {
                 locationManager.stopUpdatingLocation()
             }
+            return true
         }
     }
 

deltachat-ios/en.lproj/Localizable.strings

@@ -999,3 +999,5 @@
 "add_encrypted_account" = "Add encrypted account";
 "backup_successful" = "Backup successful";
 "backup_successful_explain_ios" = "You can find the backup in the \"Delta Chat\" folder using the \"Files\" app.\n\nMove the backup out of this folder to keep it when deleting Delta Chat.";
+"location_denied" = "Location access denied";
+"location_denied_explain_ios" = "In the system settings, enable \"Privacy/Location Services\" and set \"Delta Chat/Location\" to \"Always\" and \"Precise\".";

scripts/untranslated.xml

@@ -7,4 +7,6 @@
     <string name="add_encrypted_account">Add encrypted account</string>
     <string name="backup_successful">Backup successful</string>
     <string name="backup_successful_explain_ios">You can find the backup in the \"Delta Chat\" folder using the \"Files\" app.\n\nMove the backup out of this folder to keep it when deleting Delta Chat.</string>
+    <string name="location_denied">Location access denied</string>
+    <string name="location_denied_explain_ios">In the system settings, enable \"Privacy/Location Services\" and set \"Delta Chat/Location\" to \"Always\" and \"Precise\".</string>
 </resources>