Changelog. (#3398)

Content.Client/Changelog/ChangelogButton.cs

@@ -0,0 +1,53 @@
+using Content.Client.UserInterface.Stylesheets;
+using Robust.Client.UserInterface.Controls;
+using Robust.Shared.IoC;
+using Robust.Shared.Localization;
+
+namespace Content.Client.Changelog
+{
+    public sealed class ChangelogButton : Button
+    {
+        [Dependency] private readonly ChangelogManager _changelogManager = default!;
+
+        public ChangelogButton()
+        {
+            IoCManager.InjectDependencies(this);
+
+            OnPressed += OnOnPressed;
+        }
+
+        protected override void EnteredTree()
+        {
+            base.EnteredTree();
+
+            _changelogManager.NewChangelogEntriesChanged += UpdateStuff;
+            UpdateStuff();
+        }
+
+        protected override void ExitedTree()
+        {
+            base.ExitedTree();
+
+            _changelogManager.NewChangelogEntriesChanged -= UpdateStuff;
+        }
+
+        private void OnOnPressed(ButtonEventArgs obj)
+        {
+            new ChangelogWindow().OpenCentered();
+        }
+
+        private void UpdateStuff()
+        {
+            if (_changelogManager.NewChangelogEntries)
+            {
+                Text = Loc.GetString("changelog-button-new-entries");
+                StyleClasses.Add(StyleBase.ButtonCaution);
+            }
+            else
+            {
+                Text = Loc.GetString("changelog-button");
+                StyleClasses.Remove(StyleBase.ButtonCaution);
+            }
+        }
+    }
+}