Delivery random multipliers (#36918)

* init

* review

* init

* teehee

Content.Shared/Delivery/DeliveryModifierSystem.cs

@@ -0,0 +1,30 @@
+using Robust.Shared.Random;
+
+namespace Content.Shared.Delivery;
+
+/// <summary>
+/// System responsible for managing multipliers and logic for different delivery modifiers.
+/// </summary>
+public sealed partial class DeliveryModifierSystem : EntitySystem
+{
+    [Dependency] private readonly IRobustRandom _random = default!;
+
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        SubscribeLocalEvent<DeliveryRandomMultiplierComponent, MapInitEvent>(OnRandomMultiplierMapInit);
+        SubscribeLocalEvent<DeliveryRandomMultiplierComponent, GetDeliveryMultiplierEvent>(OnGetRandomMultiplier);
+    }
+
+    private void OnRandomMultiplierMapInit(Entity<DeliveryRandomMultiplierComponent> ent, ref MapInitEvent args)
+    {
+        ent.Comp.CurrentMultiplierOffset = _random.NextFloat(ent.Comp.MinMultiplierOffset, ent.Comp.MaxMultiplierOffset);
+        Dirty(ent);
+    }
+
+    private void OnGetRandomMultiplier(Entity<DeliveryRandomMultiplierComponent> ent, ref GetDeliveryMultiplierEvent args)
+    {
+        args.AdditiveMultiplier += ent.Comp.CurrentMultiplierOffset;
+    }
+}