scripts(backend): reformat and use status enum instead of connected bool

ColourMeOKLABGame/Assets/Scripts/Backend.cs

@@ -11,10 +11,48 @@ using UnityEngine;
 /// </summary>
 public class Backend : MonoBehaviour
 {
+    /// <summary>
+    ///     enum for the result of the authentication process
+    /// </summary>
+    // ReSharper disable once MemberCanBePrivate.Global
+    public enum AuthenticationResult
+    {
+        Ok,
+        AlreadyAuthenticated,
+        NonExistentUser,
+        AlreadyExistingUser,
+        InvalidCredentials,
+        GenericError
+    }
+
+    /// <summary>
+    ///     generic enum for the result of a database transaction
+    /// </summary>
+    // ReSharper disable once MemberCanBePrivate.Global
+    public enum DatabaseTransactionResult
+    {
+        Ok,
+        Unauthenticated,
+        Error
+    }
+
+    /// <summary>
+    ///     enum for the connection status of the firebase backend
+    /// </summary>
+    public enum FirebaseConnectionStatus
+    {
+        NotConnected,
+        Connected,
+        UpdateRequired, // "a required system component is out of date"
+        Updating, // "a required system component is updating, retrying in a bit..."
+        ExternalError, // "a system component is disabled, invalid, missing, or permissions are insufficient"
+        InternalError // "an unknown error occurred"
+    }
+
     /// <summary>
     ///     whether the backend is connected to the firebase backend
     /// </summary>
-    public bool connected;
+    public FirebaseConnectionStatus status = FirebaseConnectionStatus.NotConnected;
 
     /// <summary>
     ///     the firebase authentication object
@@ -56,6 +94,8 @@ public class Backend : MonoBehaviour
     private void OnDestroy()
     {
         SignOutUser();
+        _auth.StateChanged -= AuthStateChanged;
+        _auth = null;
     }
 
     /// <summary>
@@ -65,6 +105,7 @@ public class Backend : MonoBehaviour
     {
         FirebaseApp.CheckAndFixDependenciesAsync().ContinueWith(task =>
         {
+            // cher is this robust enough
             switch (task.Result)
             {
                 case DependencyStatus.Available:
@@ -72,28 +113,33 @@ public class Backend : MonoBehaviour
                     _auth = FirebaseAuth.GetAuth(app);
                     _auth.StateChanged += AuthStateChanged;
                     _db = FirebaseDatabase.DefaultInstance.RootReference;
-                    connected = true;
-                    Debug.Log("firebase initialised");
+                    status = FirebaseConnectionStatus.Connected;
                     break;
 
                 case DependencyStatus.UnavailableDisabled:
                 case DependencyStatus.UnavailableInvalid:
                 case DependencyStatus.UnavilableMissing:
                 case DependencyStatus.UnavailablePermission:
-                    Debug.LogError("firebase error outside of our control");
+                    status = FirebaseConnectionStatus.ExternalError;
+                    break;
+
+                case DependencyStatus.UnavailableUpdating:
+                    status = FirebaseConnectionStatus.Updating;
+                    RetryInitialiseAfterDelay();
                     break;
 
                 case DependencyStatus.UnavailableUpdaterequired:
-                case DependencyStatus.UnavailableUpdating:
-                    Debug.LogError("firebase is updating");
-                    RetryInitialiseAfterDelay();
+                    status = FirebaseConnectionStatus.UpdateRequired;
                     break;
 
                 case DependencyStatus.UnavailableOther:
                 default:
+                    status = FirebaseConnectionStatus.InternalError;
                     Debug.LogError("firebase ??? blew up or something," + task.Result);
                     break;
             }
+
+            Debug.Log("firebase status is" + status);
         });
     }
 
@@ -104,17 +150,18 @@ public class Backend : MonoBehaviour
     /// <param name="eventArgs">the event arguments</param>
     private void AuthStateChanged(object sender, EventArgs eventArgs)
     {
+        // if the user hasn't changed, do nothing
         if (_auth.CurrentUser == _user) return;
+
+        // if the user has changed, check if they've signed in or out
         var signedIn = _user != _auth.CurrentUser && _auth.CurrentUser != null;
-        switch (signedIn)
-        {
-            case false when _user != null:
-                _onSignOutCallback(_user);
-                break;
-            case true:
-                _onSignInCallback(_auth.CurrentUser);
-                break;
-        }
+
+        // if we're not signed in, but we still hold _user locally, we've signed out
+        if (!signedIn && _user != null) _onSignOutCallback(_user);
+
+        // they have signed in, update _user
+        _user = _auth.CurrentUser;
+        if (signedIn) _onSignInCallback(_user);
     }
 
     /// <summary>
@@ -168,7 +215,7 @@ public class Backend : MonoBehaviour
     {
         return _user;
     }
-    
+
     /// <summary>
     ///     abstraction function to sign out the user
     /// </summary>
@@ -233,29 +280,4 @@ public class Backend : MonoBehaviour
         public float Rating;
         public int PlayCount;
     }
-
-    /// <summary>
-    ///     enum for the result of the authentication process
-    /// </summary>
-    // ReSharper disable once MemberCanBePrivate.Global
-    public enum AuthenticationResult
-    {
-        Ok,
-        AlreadyAuthenticated,
-        NonExistentUser,
-        AlreadyExistingUser,
-        InvalidCredentials,
-        GenericError
-    }
-
-    /// <summary>
-    ///     generic enum for the result of a database transaction
-    /// </summary>
-    // ReSharper disable once MemberCanBePrivate.Global
-    public enum DatabaseTransactionResult
-    {
-        Ok,
-        Unauthenticated,
-        Error
-    }
 }