♻️ Replace the soft delete logic with the new shared one

DysonNetwork.Sphere/AppDatabase.cs

@@ -1,5 +1,5 @@
 using System.Linq.Expressions;
-using System.Reflection;
+using DysonNetwork.Shared.Data;
 using DysonNetwork.Shared.Models;
 using DysonNetwork.Sphere.WebReader;
 using Microsoft.EntityFrameworkCore;
@@ -142,17 +142,7 @@ public class AppDatabase(
             .HasIndex(a => a.Url)
             .IsUnique();
 
-        // Automatically apply soft-delete filter to all entities inheriting BaseModel
-        foreach (var entityType in modelBuilder.Model.GetEntityTypes())
-        {
-            if (!typeof(ModelBase).IsAssignableFrom(entityType.ClrType)) continue;
-            var method = typeof(AppDatabase)
-                .GetMethod(nameof(SetSoftDeleteFilter),
-                    BindingFlags.NonPublic | BindingFlags.Static)!
-                .MakeGenericMethod(entityType.ClrType);
-
-            method.Invoke(null, [modelBuilder]);
-        }
+        modelBuilder.ApplySoftDeleteFilters();
     }
 
     private static void SetSoftDeleteFilter<TEntity>(ModelBuilder modelBuilder)
@@ -163,30 +153,7 @@ public class AppDatabase(
 
     public override async Task<int> SaveChangesAsync(CancellationToken cancellationToken = default)
     {
-        var now = SystemClock.Instance.GetCurrentInstant();
-
-        foreach (var entry in ChangeTracker.Entries<ModelBase>())
-        {
-            switch (entry.State)
-            {
-                case EntityState.Added:
-                    entry.Entity.CreatedAt = now;
-                    entry.Entity.UpdatedAt = now;
-                    break;
-                case EntityState.Modified:
-                    entry.Entity.UpdatedAt = now;
-                    break;
-                case EntityState.Deleted:
-                    entry.State = EntityState.Modified;
-                    entry.Entity.DeletedAt = now;
-                    break;
-                case EntityState.Detached:
-                case EntityState.Unchanged:
-                default:
-                    break;
-            }
-        }
-
+        this.ApplyAuditableAndSoftDelete();
         return await base.SaveChangesAsync(cancellationToken);
     }
 }
@@ -252,34 +219,3 @@ public class AppDatabaseFactory : IDesignTimeDbContextFactory<AppDatabase>
     }
 }
 
-public static class OptionalQueryExtensions
-{
-    public static IQueryable<T> If<T>(
-        this IQueryable<T> source,
-        bool condition,
-        Func<IQueryable<T>, IQueryable<T>> transform
-    )
-    {
-        return condition ? transform(source) : source;
-    }
-
-    public static IQueryable<T> If<T, TP>(
-        this IIncludableQueryable<T, TP> source,
-        bool condition,
-        Func<IIncludableQueryable<T, TP>, IQueryable<T>> transform
-    )
-        where T : class
-    {
-        return condition ? transform(source) : source;
-    }
-
-    public static IQueryable<T> If<T, TP>(
-        this IIncludableQueryable<T, IEnumerable<TP>> source,
-        bool condition,
-        Func<IIncludableQueryable<T, IEnumerable<TP>>, IQueryable<T>> transform
-    )
-        where T : class
-    {
-        return condition ? transform(source) : source;
-    }
-}