Add interaction checks to all interactions (#923)

Content.Server/Utility/InteractionChecks.cs

@@ -0,0 +1,100 @@
+using System;
+using Content.Server.GameObjects.EntitySystems;
+using Content.Shared.Interfaces;
+using Content.Shared.Physics;
+using Robust.Shared.GameObjects.Systems;
+using Robust.Shared.Interfaces.GameObjects;
+using Robust.Shared.Interfaces.Map;
+using Robust.Shared.IoC;
+using Robust.Shared.Localization;
+using Robust.Shared.Map;
+using Robust.Shared.Maths;
+
+namespace Content.Server.Utility
+{
+    /// <summary>
+    /// Convenient methods for checking for various conditions commonly needed
+    /// for interactions.
+    /// </summary>
+    public static class InteractionChecks
+    {
+
+        /// <summary>
+        /// Default interaction check for targeted attack interaction types.
+        /// Same as <see cref="SharedInteractionSystem.InRangeUnobstructed"/>, but defaults to allow inside blockers.
+        /// Validates that attacker is in range of the attacked entity. Additionally shows a popup if
+        /// validation fails.
+        /// </summary>
+        public static bool InRangeUnobstructed(ITargetedAttackEventArgs eventArgs, bool insideBlockerValid = true)
+        {
+            if (!EntitySystem.Get<SharedInteractionSystem>().InRangeUnobstructed(eventArgs.User.Transform.MapPosition,
+                eventArgs.Attacked.Transform.WorldPosition, ignoredEnt: eventArgs.Attacked, insideBlockerValid: insideBlockerValid))
+            {
+                var localizationManager = IoCManager.Resolve<ILocalizationManager>();
+                eventArgs.Attacked.PopupMessage(eventArgs.User, localizationManager.GetString("You can't reach there!"));
+                return false;
+            }
+
+            return true;
+        }
+
+        /// <summary>
+        /// Default interaction check for after attack interaction types.
+        /// Same as <see cref="SharedInteractionSystem.InRangeUnobstructed"/>, but defaults to allow inside blockers.
+        /// Validates that attacker is in range of the attacked entity, if there is such an entity.
+        /// If there is no attacked entity, validates that they are in range of the clicked position.
+        /// Additionally shows a popup if validation fails.
+        /// </summary>
+        public static bool InRangeUnobstructed(AfterAttackEventArgs eventArgs, bool insideBlockerValid = true)
+        {
+            if (eventArgs.Attacked != null)
+            {
+                if (!EntitySystem.Get<SharedInteractionSystem>().InRangeUnobstructed(eventArgs.User.Transform.MapPosition,
+                    eventArgs.Attacked.Transform.WorldPosition, ignoredEnt: eventArgs.Attacked, insideBlockerValid: insideBlockerValid))
+                {
+                    var localizationManager = IoCManager.Resolve<ILocalizationManager>();
+                    eventArgs.Attacked.PopupMessage(eventArgs.User, localizationManager.GetString("You can't reach there!"));
+                    return false;
+                }
+            }
+            else
+            {
+                var mapManager = IoCManager.Resolve<IMapManager>();
+                if (!EntitySystem.Get<SharedInteractionSystem>().InRangeUnobstructed(eventArgs.User.Transform.MapPosition,
+                    eventArgs.ClickLocation.ToMapPos(mapManager), ignoredEnt: eventArgs.User, insideBlockerValid: insideBlockerValid))
+                {
+                    var localizationManager = IoCManager.Resolve<ILocalizationManager>();
+                    eventArgs.User.PopupMessage(eventArgs.User, localizationManager.GetString("You can't reach there!"));
+                    return false;
+                }
+            }
+
+
+            return true;
+        }
+
+        /// <summary>
+        /// Convenient static alternative to <see cref="SharedInteractionSystem.InRangeUnobstructed"/>, which also
+        /// shows a popup message if not in range.
+        /// </summary>
+        public static bool InRangeUnobstructed(IEntity user, Vector2 targetWorldCoords,
+            float range = SharedInteractionSystem.InteractionRange,
+            int collisionMask = (int) CollisionGroup.Impassable, IEntity ignoredEnt = null,
+            bool insideBlockerValid = false)
+        {
+            var interactionSystem = EntitySystem.Get<SharedInteractionSystem>();
+            if (!interactionSystem.InRangeUnobstructed(user.Transform.MapPosition, targetWorldCoords, range, collisionMask,
+                ignoredEnt, insideBlockerValid))
+            {
+                var localizationManager = IoCManager.Resolve<ILocalizationManager>();
+                user.PopupMessage(user, localizationManager.GetString("You can't reach there!"));
+                return false;
+            }
+
+            return true;
+        }
+
+
+
+    }
+}