Actions System + UI (#2710)

Co-authored-by: Vera Aguilera Puerto <6766154+Zumorica@users.noreply.github.com>

Content.Shared/Actions/IToggleItemAction.cs

@@ -0,0 +1,42 @@
+using Robust.Shared.Interfaces.GameObjects;
+
+namespace Content.Shared.Actions
+{
+    /// <summary>
+    /// Item action which can be toggled on and off
+    /// </summary>
+    public interface IToggleItemAction : IItemActionBehavior
+    {
+        /// <summary>
+        /// Invoked when the action will be toggled on/off.
+        /// Implementation should perform the server side logic of whatever
+        /// happens when it is toggled on / off.
+        /// </summary>
+        /// <returns>true if the attempt to toggle was successful, meaning the state should be toggled to the desired value.
+        /// False to leave toggle status unchanged. This is NOT returning the new toggle status, it is only returning
+        /// whether the attempt to toggle to the indicated status was successful.
+        ///
+        /// Note that it's still okay if the implementation directly modifies toggle status via ItemActionsComponent,
+        /// this is just an additional level of safety to ensure implementations will always
+        /// explicitly indicate if the toggle status should be changed.</returns>
+        bool DoToggleAction(ToggleItemActionEventArgs args);
+    }
+
+    public class ToggleItemActionEventArgs : ItemActionEventArgs
+    {
+        /// <summary>
+        /// True if the toggle was toggled on, false if it was toggled off
+        /// </summary>
+        public readonly bool ToggledOn;
+        /// <summary>
+        /// Opposite of ToggledOn
+        /// </summary>
+        public bool ToggledOff => !ToggledOn;
+
+        public ToggleItemActionEventArgs(IEntity performer, bool toggledOn, IEntity item,
+            ItemActionType actionType) : base(performer, item, actionType)
+        {
+            ToggledOn = toggledOn;
+        }
+    }
+}