Prevent closed drinks from transferring reagents (#7329)

* Prevent closed drinks from transferring reagents

* Inherit from cancellable event

Content.Server/Chemistry/Components/SolutionTransferComponent.cs

@@ -113,12 +113,12 @@ namespace Content.Server.Chemistry.Components
 
         async Task<bool> IAfterInteract.AfterInteract(AfterInteractEventArgs eventArgs)
         {
-            var solutionsSys = EntitySystem.Get<SolutionContainerSystem>();
-
             if (!eventArgs.CanReach || eventArgs.Target == null)
                 return false;
 
             var target = eventArgs.Target!.Value;
+            var solutionsSys = EntitySystem.Get<SolutionContainerSystem>();
+            var transferSystem = EntitySystem.Get<SolutionTransferSystem>();
 
             //Special case for reagent tanks, because normally clicking another container will give solution, not take it.
             if (CanReceive  && !_entities.HasComponent<RefillableSolutionComponent>(target) // target must not be refillable (e.g. Reagent Tanks)
@@ -135,7 +135,7 @@ namespace Content.Server.Chemistry.Components
                     transferAmount = FixedPoint2.Min(transferAmount, (FixedPoint2) refill.MaxRefill); // if the receiver has a smaller transfer limit, use that instead
                 }
 
-                var transferred = DoTransfer(eventArgs.User, target, targetDrain, Owner, ownerRefill, transferAmount);
+                var transferred = transferSystem.Transfer(eventArgs.User, target, targetDrain, Owner, ownerRefill, transferAmount);
                 if (transferred > 0)
                 {
                     var toTheBrim = ownerRefill.AvailableVolume == 0;
@@ -160,7 +160,7 @@ namespace Content.Server.Chemistry.Components
                     transferAmount = FixedPoint2.Min(transferAmount, (FixedPoint2) refill.MaxRefill);
                 }
 
-                var transferred = DoTransfer(eventArgs.User, Owner, ownerDrain, target, targetRefill, transferAmount);
+                var transferred = transferSystem.Transfer(eventArgs.User, Owner, ownerDrain, target, targetRefill, transferAmount);
 
                 if (transferred > 0)
                 {
@@ -175,36 +175,5 @@ namespace Content.Server.Chemistry.Components
 
             return false;
         }
-
-        /// <returns>The actual amount transferred.</returns>
-        private static FixedPoint2 DoTransfer(EntityUid user,
-            EntityUid sourceEntity,
-            Solution source,
-            EntityUid targetEntity,
-            Solution target,
-            FixedPoint2 amount)
-        {
-
-            if (source.DrainAvailable == 0)
-            {
-                sourceEntity.PopupMessage(user,
-                    Loc.GetString("comp-solution-transfer-is-empty", ("target", sourceEntity)));
-                return FixedPoint2.Zero;
-            }
-
-            if (target.AvailableVolume == 0)
-            {
-                targetEntity.PopupMessage(user,
-                    Loc.GetString("comp-solution-transfer-is-full", ("target", targetEntity)));
-                return FixedPoint2.Zero;
-            }
-
-            var actualAmount = FixedPoint2.Min(amount, FixedPoint2.Min(source.DrainAvailable, target.AvailableVolume));
-
-            var solution = EntitySystem.Get<SolutionContainerSystem>().Drain(sourceEntity, source, actualAmount);
-            EntitySystem.Get<SolutionContainerSystem>().Refill(targetEntity, target, solution);
-
-            return actualAmount;
-        }
     }
 }

Content.Server/Chemistry/EntitySystems/SolutionTransferSystem.cs

@@ -5,6 +5,7 @@ using Robust.Shared.GameObjects;
 using Robust.Shared.Localization;
 using Robust.Server.GameObjects;
 using System.Collections.Generic;
+using Content.Shared.Chemistry.Components;
 using Content.Shared.Chemistry.Reagent;
 using Content.Shared.FixedPoint;
 using Content.Shared.Popups;
@@ -66,5 +67,86 @@ namespace Content.Server.Chemistry.EntitySystems
                 args.Verbs.Add(verb);
             }
         }
+
+        /// <summary>
+        /// Transfer from a solution to another.
+        /// </summary>
+        /// <returns>The actual amount transferred.</returns>
+        public FixedPoint2 Transfer(EntityUid user,
+            EntityUid sourceEntity,
+            Solution source,
+            EntityUid targetEntity,
+            Solution target,
+            FixedPoint2 amount)
+        {
+            var transferAttempt = new SolutionTransferAttemptEvent(sourceEntity, targetEntity);
+
+            // Check if the source is cancelling the transfer
+            RaiseLocalEvent(sourceEntity, transferAttempt);
+            if (transferAttempt.Cancelled)
+            {
+                sourceEntity.PopupMessage(user, transferAttempt.CancelReason!);
+                return FixedPoint2.Zero;
+            }
+
+            if (source.DrainAvailable == 0)
+            {
+                sourceEntity.PopupMessage(user,
+                    Loc.GetString("comp-solution-transfer-is-empty", ("target", sourceEntity)));
+                return FixedPoint2.Zero;
+            }
+
+            // Check if the target is cancelling the transfer
+            RaiseLocalEvent(targetEntity, transferAttempt);
+            if (transferAttempt.Cancelled)
+            {
+                sourceEntity.PopupMessage(user, transferAttempt.CancelReason!);
+                return FixedPoint2.Zero;
+            }
+
+            if (target.AvailableVolume == 0)
+            {
+                targetEntity.PopupMessage(user,
+                    Loc.GetString("comp-solution-transfer-is-full", ("target", targetEntity)));
+                return FixedPoint2.Zero;
+            }
+
+            var actualAmount = FixedPoint2.Min(amount, FixedPoint2.Min(source.DrainAvailable, target.AvailableVolume));
+
+            var solutionSystem = Get<SolutionContainerSystem>();
+            var solution = solutionSystem.Drain(sourceEntity, source, actualAmount);
+            solutionSystem.Refill(targetEntity, target, solution);
+
+            return actualAmount;
+        }
+    }
+
+    /// <summary>
+    /// Raised when attempting to transfer from one solution to another.
+    /// </summary>
+    public sealed class SolutionTransferAttemptEvent : CancellableEntityEventArgs
+    {
+        public SolutionTransferAttemptEvent(EntityUid from, EntityUid to)
+        {
+            From = from;
+            To = to;
+        }
+
+        public EntityUid From { get; }
+        public EntityUid To { get; }
+
+        /// <summary>
+        /// Why the transfer has been cancelled.
+        /// </summary>
+        public string? CancelReason { get; private set; }
+
+        /// <summary>
+        /// Cancels the transfer.
+        /// </summary>
+        public void Cancel(string reason)
+        {
+            base.Cancel();
+            CancelReason = reason;
+        }
     }
 }

Content.Server/Nutrition/EntitySystems/DrinkSystem.cs

@@ -54,6 +54,7 @@ namespace Content.Server.Nutrition.EntitySystems
             SubscribeLocalEvent<DrinkComponent, UseInHandEvent>(OnUse);
             SubscribeLocalEvent<DrinkComponent, AfterInteractEvent>(AfterInteract);
             SubscribeLocalEvent<DrinkComponent, ExaminedEvent>(OnExamined);
+            SubscribeLocalEvent<DrinkComponent, SolutionTransferAttemptEvent>(OnTransferAttempt);
             SubscribeLocalEvent<SharedBodyComponent, DrinkEvent>(OnDrink);
             SubscribeLocalEvent<DrinkCancelledEvent>(OnDrinkCancelled);
         }
@@ -94,17 +95,6 @@ namespace Content.Server.Nutrition.EntitySystems
             {
                 appearance.SetData(DrinkCanStateVisual.Opened, opened);
             }
-
-            if (opened)
-            {
-                EntityManager.EnsureComponent<RefillableSolutionComponent>(uid).Solution= component.SolutionName;
-                EntityManager.EnsureComponent<DrainableSolutionComponent>(uid).Solution= component.SolutionName;
-            }
-            else
-            {
-                EntityManager.RemoveComponent<RefillableSolutionComponent>(uid);
-                EntityManager.RemoveComponent<DrainableSolutionComponent>(uid);
-            }
         }
 
         private void AfterInteract(EntityUid uid, DrinkComponent component, AfterInteractEvent args)
@@ -163,6 +153,10 @@ namespace Content.Server.Nutrition.EntitySystems
             }
 
             UpdateAppearance(component);
+
+            // Synchronize solution in drink
+            EnsureComp<RefillableSolutionComponent>(uid).Solution = component.SolutionName;
+            EnsureComp<DrainableSolutionComponent>(uid).Solution = component.SolutionName;
         }
 
         private void OnSolutionChange(EntityUid uid, DrinkComponent component, SolutionChangedEvent args)
@@ -183,6 +177,15 @@ namespace Content.Server.Nutrition.EntitySystems
             appearance.SetData(DrinkCanStateVisual.Opened, component.Opened);
         }
 
+        private void OnTransferAttempt(EntityUid uid, DrinkComponent component, SolutionTransferAttemptEvent args)
+        {
+            if (!component.Opened)
+            {
+                args.Cancel(Loc.GetString("drink-component-try-use-drink-not-open",
+                    ("owner", EntityManager.GetComponent<MetaDataComponent>(component.Owner).EntityName)));
+            }
+        }
+
         private bool TryDrink(EntityUid user, EntityUid target, DrinkComponent drink)
         {
             // cannot stack do-afters