refactor project structure

PluralKit.Bot/Preconditions.cs

@@ -0,0 +1,34 @@
+using System;
+using System.Threading.Tasks;
+using Discord.Commands;
+
+namespace PluralKit.Bot {
+    class MustHaveSystem : PreconditionAttribute
+    {
+        public override async Task<PreconditionResult> CheckPermissionsAsync(ICommandContext context, CommandInfo command, IServiceProvider services)
+        {
+            var c = context as PKCommandContext;
+            if (c == null) return PreconditionResult.FromError("Must be called on a PKCommandContext (should never happen!)");
+            if (c.SenderSystem == null) return PreconditionResult.FromError(Errors.NoSystemError);
+            return PreconditionResult.FromSuccess();
+        }
+    }
+
+    class MustPassOwnMember : PreconditionAttribute
+    {
+        public override async Task<PreconditionResult> CheckPermissionsAsync(ICommandContext context, CommandInfo command, IServiceProvider services)
+        {
+            // OK when:
+            // - Sender has a system
+            // - Sender passes a member as a context parameter
+            // - Sender owns said member 
+
+            var c = context as PKCommandContext;
+            if (c == null) 
+            if (c.SenderSystem == null) return PreconditionResult.FromError(Errors.NoSystemError);
+            if (c.GetContextEntity<PKMember>() == null) return PreconditionResult.FromError(Errors.MissingMemberError);
+            if (c.GetContextEntity<PKMember>().System != c.SenderSystem.Id) return PreconditionResult.FromError(Errors.NotOwnMemberError);
+            return PreconditionResult.FromSuccess();
+        }
+    }
+}