From 3bfac250279141aef87cf56129f84c9d368d3bbb Mon Sep 17 00:00:00 2001
From: soul <s@x>
Date: Thu, 22 Oct 2026 20:02:16 +0200
Subject: [PATCH] New Game is a two-pane scenario picker: names by group,
 selected brief/seed/ambient, one Launch, arrows and Enter

MainMenu.AddScenarios and the per-scenario launching buttons are deleted; the seven Clear+Title pairs collapse into Next. The main menu EventSystem no longer deselects on background click so the arrows keep working.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>
---
 Assets/Scenes/Main Menu.unity       |   2 +-
 Assets/Scripts/UI/MainMenu.cs       |  68 +++++++--------
 Assets/Scripts/UI/ScenarioPicker.cs | 130 ++++++++++++++++++++++++++++
 3 files changed, 162 insertions(+), 38 deletions(-)
 create mode 100644 Assets/Scripts/UI/ScenarioPicker.cs

diff --git a/Assets/Scenes/Main Menu.unity b/Assets/Scenes/Main Menu.unity
index 4fafe8336..c1f111f09 100644
--- a/Assets/Scenes/Main Menu.unity	
+++ b/Assets/Scenes/Main Menu.unity	
@@ -525,7 +525,7 @@ MonoBehaviour:
     type: 3}
   m_TrackedDeviceOrientationAction: {fileID: 1025543830046995696, guid: ca9f5fa95ffab41fb9a615ab714db018,
     type: 3}
-  m_DeselectOnBackgroundClick: 1
+  m_DeselectOnBackgroundClick: 0
   m_PointerBehavior: 0
 --- !u!114 &553528108
 MonoBehaviour:
diff --git a/Assets/Scripts/UI/MainMenu.cs b/Assets/Scripts/UI/MainMenu.cs
index e72ce5263..401f4b2af 100644
--- a/Assets/Scripts/UI/MainMenu.cs
+++ b/Assets/Scripts/UI/MainMenu.cs
@@ -23,7 +23,7 @@ public class MainMenu : MonoBehaviour
     public float FadeAlphaExponent = 2;
     public float FadePositionExponent = 2;
 
-    private (PropertiesPanel panel, CanvasGroup group) _currentMenu, _nextMenu;
+    private (PropertiesPanel panel, CanvasGroup group, PropertiesPanel detail) _currentMenu, _nextMenu;
     private bool _fadeFromRight;
     private float _fadeLerp;
     private bool _fading;
@@ -38,10 +38,14 @@ public class MainMenu : MonoBehaviour
         _panelPosition = PanelPrototype.transform.position;
         
         var panel1 = PanelPrototype.Instantiate<PropertiesPanel>();
-        _currentMenu = (panel1, panel1.GetComponent<CanvasGroup>());
+        var detail1 = PanelPrototype.Instantiate<PropertiesPanel>();
+        ScenarioPicker.Dock(detail1, panel1);
+        _currentMenu = (panel1, panel1.GetComponent<CanvasGroup>(), detail1);
         
         var panel2 = PanelPrototype.Instantiate<PropertiesPanel>();
-        _nextMenu = (panel2, panel2.GetComponent<CanvasGroup>());
+        var detail2 = PanelPrototype.Instantiate<PropertiesPanel>();
+        ScenarioPicker.Dock(detail2, panel2);
+        _nextMenu = (panel2, panel2.GetComponent<CanvasGroup>(), detail2);
 
         _currentMenu.panel.gameObject.SetActive(false);
         //_saveDirectory = ActionGameManager.GameDataDirectory.CreateSubdirectory("Saves");
@@ -74,7 +78,7 @@ public class MainMenu : MonoBehaviour
         }
     }
 
-    private string TitleSubtitle(string title, string subtitle) => $"{title}\n<smallcaps><size=50%>{subtitle}";
+    public static string TitleSubtitle(string title, string subtitle) => $"{title}\n<smallcaps><size=50%>{subtitle}";
 
     private void Fade(bool fromRight)
     {
@@ -87,10 +91,18 @@ public class MainMenu : MonoBehaviour
 
     private static bool _exclusionsShown;
 
-    private void ShowMain()
+    // Starts the next screen on an empty panel with a title and its scenario detail pane hidden and empty.
+    private void Next(string title)
     {
         _nextMenu.panel.Clear();
-        _nextMenu.panel.Title.text = TitleSubtitle("aetheria", "terminus");
+        _nextMenu.panel.Title.text = title;
+        _nextMenu.detail.Clear();
+        _nextMenu.detail.gameObject.SetActive(false);
+    }
+
+    private void ShowMain()
+    {
+        Next(TitleSubtitle("aetheria", "terminus"));
         if (ActionGameManager.CurrentGalaxy == null)
         {
             // No run is live: at the title, after death, or after a new run failed to start. A saved run exists only as
@@ -131,31 +143,18 @@ public class MainMenu : MonoBehaviour
     // to set up a run and the test arenas are listed only in editor and development builds.
     private void ShowScenarios()
     {
-        _nextMenu.panel.Clear();
-        _nextMenu.panel.Title.text = TitleSubtitle("new game", "scenarios");
-        AddScenarios(Scenarios.Modes);
+        Next(TitleSubtitle("new game", "scenarios"));
+        var groups = new List<(string label, Scenario[] scenarios)> { ("modes", Scenarios.Modes) };
         if (Debug.isDebugBuild)
         {
-            _nextMenu.panel.AddSection("development");
-            AddScenarios(Scenarios.Development);
-            _nextMenu.panel.AddSection("test arenas");
-            AddScenarios(Scenarios.Tests);
+            groups.Add(("development", Scenarios.Development));
+            groups.Add(("test arenas", Scenarios.Tests));
         }
-        _nextMenu.panel.AddButton("Back",
-            () =>
-            {
-                ShowMain();
-                Fade(false);
-            });
-    }
-
-    private void AddScenarios(IEnumerable<Scenario> scenarios)
-    {
-        foreach (var scenario in scenarios)
+        ScenarioPicker.Show(_nextMenu.panel, _nextMenu.detail, groups, Launch, () =>
         {
-            _nextMenu.panel.AddButton(scenario.Name, () => Launch(scenario));
-            _nextMenu.panel.AddProperty(() => scenario.Brief);
-        }
+            ShowMain();
+            Fade(false);
+        });
     }
 
     // The only way into a new run: generates the scenario's galaxy off the main thread and enters the game, where
@@ -263,8 +262,7 @@ public class MainMenu : MonoBehaviour
 
     private void ShowSettings()
     {
-        _nextMenu.panel.Clear();
-        _nextMenu.panel.Title.text = "settings";
+        Next("settings");
         _nextMenu.panel.AddButton("Gameplay",
             () =>
             {
@@ -299,8 +297,7 @@ public class MainMenu : MonoBehaviour
     
     private void ShowGameplaySettings()
     {
-        _nextMenu.panel.Clear();
-        _nextMenu.panel.Title.text = TitleSubtitle("gameplay", "settings");
+        Next(TitleSubtitle("gameplay", "settings"));
         _nextMenu.panel.AddField("Name", 
             () => ActionGameManager.PlayerSettings.Name,
             s => ActionGameManager.PlayerSettings.Name = s);
@@ -322,8 +319,7 @@ public class MainMenu : MonoBehaviour
 
     private void ShowGraphicsSettings()
     {
-        _nextMenu.panel.Clear();
-        _nextMenu.panel.Title.text = TitleSubtitle("graphics", "settings");
+        Next(TitleSubtitle("graphics", "settings"));
         _nextMenu.panel.AddField("Nebula Quality",
             () => (int)ActionGameManager.PlayerSettings.GraphicsSettings.NebulaQuality,
             i =>
@@ -347,8 +343,7 @@ public class MainMenu : MonoBehaviour
 
     private void ShowInputSettings()
     {
-        _nextMenu.panel.Clear();
-        _nextMenu.panel.Title.text = TitleSubtitle("input", "settings");
+        Next(TitleSubtitle("input", "settings"));
         _nextMenu.panel.AddButton("Back",
             () =>
             {
@@ -359,8 +354,7 @@ public class MainMenu : MonoBehaviour
 
     private void ShowAudioSettings()
     {
-        _nextMenu.panel.Clear();
-        _nextMenu.panel.Title.text = TitleSubtitle("audio", "settings");
+        Next(TitleSubtitle("audio", "settings"));
         _nextMenu.panel.AddButton("Back",
             () =>
             {
diff --git a/Assets/Scripts/UI/ScenarioPicker.cs b/Assets/Scripts/UI/ScenarioPicker.cs
new file mode 100644
index 000000000..4d6ab393e
--- /dev/null
+++ b/Assets/Scripts/UI/ScenarioPicker.cs
@@ -0,0 +1,130 @@
+using System;
+using System.Collections.Generic;
+using UniRx;
+using UniRx.Triggers;
+using UnityEngine;
+using UnityEngine.EventSystems;
+using UnityEngine.UI;
+
+// The New Game screen: scenario names on the left pane by group, the selected scenario's brief, seed and ambient on a
+// docked right pane, one Launch. This class owns which scenario is selected (one index into the rows it built);
+// everything the screen shows about a scenario, and what Launch and Enter launch, reads that index. Keys arrive only as
+// Input System UI events on the focused Launch button, so Enter and a mouse click are the same Button.onClick.
+public sealed class ScenarioPicker
+{
+    private readonly List<Scenario> _scenarios = new List<Scenario>();
+    private readonly List<string> _groupLabels = new List<string>();
+    private readonly List<Button> _rows = new List<Button>();
+    private readonly List<ColorBlock> _rowColors = new List<ColorBlock>();
+    private readonly PropertiesPanel _detail;
+    private readonly Action<Scenario> _launch;
+    private readonly Action _back;
+    private Button _launchButton;
+    private int _selected;
+
+    private ScenarioPicker(PropertiesPanel detail, Action<Scenario> launch, Action back)
+    {
+        _detail = detail;
+        _launch = launch;
+        _back = back;
+    }
+
+    // The scenario the detail pane describes and Launch will launch.
+    public Scenario Selected => _scenarios[_selected];
+
+    // Parks the detail pane beside the list pane: a child of it, outside its layout, hidden until Show.
+    public static void Dock(PropertiesPanel detail, PropertiesPanel list, float width = 480, float gap = 16)
+    {
+        var rect = (RectTransform) detail.transform;
+        rect.SetParent(list.transform, false);
+        detail.gameObject.AddComponent<LayoutElement>().ignoreLayout = true;
+        rect.anchorMin = new Vector2(1, 0);
+        rect.anchorMax = new Vector2(1, 1);
+        rect.pivot = new Vector2(0, .5f);
+        rect.anchoredPosition = new Vector2(gap, 0);
+        rect.sizeDelta = new Vector2(width, 0);
+        detail.gameObject.SetActive(false);
+    }
+
+    // Builds both panes for the groups, shows the detail pane, selects the first scenario and focuses Launch.
+    public static ScenarioPicker Show(PropertiesPanel list, PropertiesPanel detail,
+        IReadOnlyList<(string label, Scenario[] scenarios)> groups, Action<Scenario> launch, Action back)
+    {
+        var picker = new ScenarioPicker(detail, launch, back);
+        foreach (var group in groups)
+        {
+            if (groups.Count > 1) list.AddSection(group.label);
+            foreach (var scenario in group.scenarios)
+            {
+                var index = picker._scenarios.Count;
+                picker._scenarios.Add(scenario);
+                picker._groupLabels.Add(group.label);
+                var row = list.AddButton(scenario.Name, () => picker.Select(index));
+                picker.Track(row.Button);
+                picker._rows.Add(row.Button);
+                picker._rowColors.Add(row.Button.colors);
+            }
+        }
+        picker.Track(list.AddButton("Back", picker.Back).Button);
+
+        detail.Clear();
+        detail.gameObject.SetActive(true);
+        detail.AddProperty(() => picker.Selected.Brief);
+        detail.AddProperty("Seed", () => picker.Selected.Seed == 0 ? "new each launch" : picker.Selected.Seed.ToString());
+        detail.AddProperty("Ambient", () => picker.Selected.Ambient ? "on" : "off");
+        picker._launchButton = detail.AddButton("Launch", picker.Activate).Button;
+        picker.Track(picker._launchButton);
+        picker._launchButton.OnMoveAsObservable().Subscribe(move =>
+        {
+            if (move.moveDir == MoveDirection.Up) picker.Step(-1);
+            else if (move.moveDir == MoveDirection.Down) picker.Step(1);
+        });
+        picker._launchButton.OnCancelAsObservable().Subscribe(_ => picker.Back());
+
+        picker.Select(0);
+        return picker;
+    }
+
+    // Takes a button out of Unity's navigation so a click never moves focus and Move never walks automatic navigation.
+    private void Track(Button button) => button.navigation = new Navigation { mode = Navigation.Mode.None };
+
+    // Moves the selection one row, stopping at either end.
+    private void Step(int delta) => Select(_selected + delta);
+
+    // Makes one row the selection: clamps the index, redraws the highlight and title, and returns focus to Launch.
+    private void Select(int index)
+    {
+        _selected = Mathf.Clamp(index, 0, _scenarios.Count - 1);
+        for (var i = 0; i < _rows.Count; i++)
+        {
+            var colors = _rowColors[i];
+            if (i == _selected)
+            {
+                colors.normalColor = colors.highlightedColor;
+                colors.selectedColor = colors.highlightedColor;
+            }
+            _rows[i].colors = colors;
+        }
+        _detail.Title.text = MainMenu.TitleSubtitle(Selected.Name, _groupLabels[_selected]);
+        Focus(_launchButton.gameObject);
+    }
+
+    // Launches the selection; focus is cleared first so a repeated Enter or a second click cannot launch twice.
+    private void Activate()
+    {
+        Focus(null);
+        _launch(Selected);
+    }
+
+    // Leaves the screen; the same path for the Back button and Cancel.
+    private void Back()
+    {
+        Focus(null);
+        _back();
+    }
+
+    private static void Focus(GameObject target)
+    {
+        if (EventSystem.current != null) EventSystem.current.SetSelectedGameObject(target);
+    }
+}