Paper and pen (#582)

* A very basic paper and pen implementation

* Removes SharedWriteComponent

* Update ContentNetIDs.cs

Content.Server/GameObjects/Components/Paper/PaperComponent.cs

@@ -0,0 +1,78 @@
+using Content.Server.GameObjects.EntitySystems;
+using Content.Shared.GameObjects.Components;
+using Robust.Server.GameObjects;
+using Robust.Server.GameObjects.Components.UserInterface;
+using Robust.Server.Interfaces.GameObjects;
+using Robust.Shared.GameObjects;
+using Robust.Shared.Utility;
+
+namespace Content.Server.GameObjects.Components.Interactable
+{
+    [RegisterComponent]
+    public class PaperComponent : SharedPaperComponent, IExamine, IAttackBy, IUse
+    {
+
+        private BoundUserInterface _userInterface;
+        private string _content;
+        private PaperAction _mode;
+
+        public override void Initialize()
+        {
+            base.Initialize();
+            _userInterface = Owner.GetComponent<ServerUserInterfaceComponent>()
+                .GetBoundUserInterface(PaperUiKey.Key);
+            _userInterface.OnReceiveMessage += OnUiReceiveMessage;
+            _content = "";
+            _mode = PaperAction.Read;
+            UpdateUserInterface();
+        }
+        private void UpdateUserInterface()
+        {
+            _userInterface.SetState(new PaperBoundUserInterfaceState(_content, _mode));
+        }
+
+        public void Examine(FormattedMessage message)
+        {
+            message.AddMarkup(_content);
+        }
+
+        public bool UseEntity(UseEntityEventArgs eventArgs)
+        {
+            if (!eventArgs.User.TryGetComponent(out IActorComponent actor))
+                return false;
+            _mode = PaperAction.Read;
+            UpdateUserInterface();
+            _userInterface.Open(actor.playerSession);
+            return true;
+        }
+
+        private void OnUiReceiveMessage(ServerBoundUserInterfaceMessage obj)
+        {
+            var msg = (PaperInputText) obj.Message;
+            if (string.IsNullOrEmpty(msg.Text))
+                return;
+
+            _content += msg.Text + '\n';
+
+            if (Owner.TryGetComponent(out SpriteComponent sprite))
+            {
+                sprite.LayerSetState(0, "paper_words");
+            }
+
+            UpdateUserInterface();
+        }
+
+        public bool AttackBy(AttackByEventArgs eventArgs)
+        {
+            if (!eventArgs.AttackWith.HasComponent<WriteComponent>())
+                return false;
+            if (!eventArgs.User.TryGetComponent(out IActorComponent actor))
+                return false;
+
+            _mode = PaperAction.Write;
+            UpdateUserInterface();
+            _userInterface.Open(actor.playerSession);
+            return true;
+        }
+    }
+}