Groups can now also be manually reordered

Design improvements

ModernKeePass.Application/Group/Commands/MoveGroup/MoveGroupCommand.cs

@@ -0,0 +1,33 @@
+using System.Threading.Tasks;
+using MediatR;
+using ModernKeePass.Application.Common.Interfaces;
+using ModernKeePass.Application.Group.Models;
+using ModernKeePass.Domain.Exceptions;
+
+namespace ModernKeePass.Application.Group.Commands.MoveGroup
+{
+    public class MoveGroupCommand : IRequest
+    {
+        public GroupVm ParentGroup { get; set; }
+        public GroupVm Group { get; set; }
+        public int Index { get; set; }
+
+        public class MoveGroupCommandHandler : IAsyncRequestHandler<MoveGroupCommand>
+        {
+            private readonly IDatabaseProxy _database;
+
+            public MoveGroupCommandHandler(IDatabaseProxy database)
+            {
+                _database = database;
+            }
+
+            public async Task Handle(MoveGroupCommand message)
+            {
+                if (!_database.IsOpen) throw new DatabaseClosedException();
+
+                await _database.MoveGroup(message.ParentGroup.Id, message.Group.Id, message.Index);
+                message.ParentGroup.SubGroups.Insert(message.Index, message.Group);
+            }
+        }
+    }
+}