Fix explosives (#361)

Currently explosives do no damage to tiles or damage the wrong area of the map. This is because `Owner.Delete` is called before the adjacent tiles / entities are damaged. This results in the explosives grid always being 0, and it's position always being (0, 0), meaning that the tiles in range of the explosive are not properly calculated. This fixes that (Issue #358).

Content.Server/GameObjects/Components/Explosion/ExplosiveComponent.cs

@@ -38,6 +38,7 @@ namespace Content.Server.GameObjects.Components.Explosive
         public int LightImpactRange = 0;
         public int FlashRange = 0;
 
+        private bool _beingExploded = false;
 
         public override void ExposeData(ObjectSerializer serializer)
         {
@@ -51,13 +52,16 @@ namespace Content.Server.GameObjects.Components.Explosive
 
         private bool Explosion()
         {
+            //Prevent adjacent explosives from infinitely blowing each other up.
+            if (_beingExploded) return true;
+            _beingExploded = true;
+
             var maxRange = MathHelper.Max(DevastationRange, HeavyImpactRange, LightImpactRange, 0f);
             //Entity damage calculation
             var entitiesAll = _serverEntityManager.GetEntitiesInRange(Owner.Transform.GridPosition, maxRange).ToList();
 
             foreach (var entity in entitiesAll)
             {
-                Owner.Delete();
                 if (entity == Owner)
                     continue;
                 if (!entity.Transform.IsMapTransform)
@@ -162,6 +166,7 @@ namespace Content.Server.GameObjects.Components.Explosive
                 }
             }
 
+            Owner.Delete();
             return true;
         }