Add FormBeatmapFileSelector for intermediate user-choice step

osu.Game/Graphics/UserInterfaceV2/FormFileSelector.cs

@@ -242,20 +242,26 @@ namespace osu.Game.Graphics.UserInterfaceV2
 
         Task ICanAcceptFiles.Import(ImportTask[] tasks, ImportParameters parameters) => throw new NotImplementedException();
 
+        protected virtual FileChooserPopover CreatePopover(string[] handledExtensions, Bindable<FileInfo?> current, string? chooserPath) => new FileChooserPopover(handledExtensions, current, chooserPath);
+
         public Popover GetPopover()
         {
-            var popover = new FileChooserPopover(handledExtensions, Current, initialChooserPath);
+            var popover = CreatePopover(handledExtensions, Current, initialChooserPath);
             popoverState.UnbindBindings();
             popoverState.BindTo(popover.State);
             return popover;
         }
 
-        private partial class FileChooserPopover : OsuPopover
+        protected partial class FileChooserPopover : OsuPopover
         {
             protected override string PopInSampleName => "UI/overlay-big-pop-in";
             protected override string PopOutSampleName => "UI/overlay-big-pop-out";
 
-            public FileChooserPopover(string[] handledExtensions, Bindable<FileInfo?> currentFile, string? chooserPath)
+            private readonly Bindable<FileInfo?> current = new Bindable<FileInfo?>();
+
+            protected OsuFileSelector FileSelector;
+
+            public FileChooserPopover(string[] handledExtensions, Bindable<FileInfo?> current, string? chooserPath)
                 : base(false)
             {
                 Child = new Container
@@ -264,12 +270,13 @@ namespace osu.Game.Graphics.UserInterfaceV2
                     // simplest solution to avoid underlying text to bleed through the bottom border
                     // https://github.com/ppy/osu/pull/30005#issuecomment-2378884430
                     Padding = new MarginPadding { Bottom = 1 },
-                    Child = new OsuFileSelector(chooserPath, handledExtensions)
+                    Child = FileSelector = new OsuFileSelector(chooserPath, handledExtensions)
                     {
                         RelativeSizeAxes = Axes.Both,
-                        CurrentFile = { BindTarget = currentFile }
                     },
                 };
+
+                this.current.BindTo(current);
             }
 
             [BackgroundDependencyLoader]
@@ -292,6 +299,19 @@ namespace osu.Game.Graphics.UserInterfaceV2
                     }
                 });
             }
+
+            protected override void LoadComplete()
+            {
+                base.LoadComplete();
+
+                FileSelector.CurrentFile.ValueChanged += f =>
+                {
+                    if (f.NewValue != null)
+                        OnFileSelected(f.NewValue);
+                };
+            }
+
+            protected virtual void OnFileSelected(FileInfo file) => current.Value = file;
         }
     }
 }

osu.Game/Screens/Edit/Setup/FormBeatmapFileSelector.cs

@@ -0,0 +1,161 @@
+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using System.Diagnostics;
+using System.IO;
+using osu.Framework.Allocation;
+using osu.Framework.Bindables;
+using osu.Framework.Extensions.Color4Extensions;
+using osu.Framework.Graphics;
+using osu.Framework.Graphics.Containers;
+using osu.Framework.Graphics.Shapes;
+using osu.Game.Graphics;
+using osu.Game.Graphics.Sprites;
+using osu.Game.Graphics.UserInterfaceV2;
+using osu.Game.Overlays;
+using osuTK;
+
+namespace osu.Game.Screens.Edit.Setup
+{
+    /// <summary>
+    /// A type of <see cref="FormFileSelector"/> dedicated to beatmap resources.
+    /// </summary>
+    /// <remarks>
+    /// This expands on <see cref="FormFileSelector"/> by adding an intermediate step before finalisation
+    /// to choose whether the selected file should be applied to the current difficulty or all difficulties in the set,
+    /// the user's choice is saved in <see cref="ApplyToAllDifficulties"/> before the file selection is finalised and propagated to <see cref="FormFileSelector.Current"/>.
+    /// </remarks>
+    public partial class FormBeatmapFileSelector : FormFileSelector
+    {
+        private readonly bool multipleDifficulties;
+
+        public readonly Bindable<bool> ApplyToAllDifficulties = new Bindable<bool>(true);
+
+        public FormBeatmapFileSelector(bool multipleDifficulties, params string[] handledExtensions)
+            : base(handledExtensions)
+        {
+            this.multipleDifficulties = multipleDifficulties;
+        }
+
+        protected override FileChooserPopover CreatePopover(string[] handledExtensions, Bindable<FileInfo?> current, string? chooserPath)
+        {
+            var popover = new BeatmapFileChooserPopover(handledExtensions, current, chooserPath, multipleDifficulties);
+
+            popover.ApplyToAllDifficulties.ValueChanged += v =>
+            {
+                Debug.Assert(v.NewValue != null);
+                ApplyToAllDifficulties.Value = v.NewValue.Value;
+            };
+
+            return popover;
+        }
+
+        private partial class BeatmapFileChooserPopover : FileChooserPopover
+        {
+            private readonly bool multipleDifficulties;
+
+            public readonly Bindable<bool?> ApplyToAllDifficulties = new Bindable<bool?>();
+
+            private Container changeScopeContainer = null!;
+
+            public BeatmapFileChooserPopover(string[] handledExtensions, Bindable<FileInfo?> current, string? chooserPath, bool multipleDifficulties)
+                : base(handledExtensions, current, chooserPath)
+            {
+                this.multipleDifficulties = multipleDifficulties;
+            }
+
+            [BackgroundDependencyLoader]
+            private void load(OverlayColourProvider colourProvider, OsuColour colours)
+            {
+                Add(changeScopeContainer = new InputBlockingContainer
+                {
+                    Alpha = 0f,
+                    RelativeSizeAxes = Axes.Both,
+                    Children = new Drawable[]
+                    {
+                        new Box
+                        {
+                            Colour = colourProvider.Background6.Opacity(0.9f),
+                            RelativeSizeAxes = Axes.Both,
+                        },
+                        new Container
+                        {
+                            Anchor = Anchor.Centre,
+                            Origin = Anchor.Centre,
+                            Masking = true,
+                            CornerRadius = 10f,
+                            AutoSizeAxes = Axes.Both,
+                            Children = new Drawable[]
+                            {
+                                new Box
+                                {
+                                    Colour = colourProvider.Background5,
+                                    RelativeSizeAxes = Axes.Both,
+                                },
+                                new FillFlowContainer
+                                {
+                                    Anchor = Anchor.Centre,
+                                    Origin = Anchor.Centre,
+                                    AutoSizeAxes = Axes.Both,
+                                    Direction = FillDirection.Vertical,
+                                    Spacing = new Vector2(0f, 10f),
+                                    Margin = new MarginPadding(30),
+                                    Children = new Drawable[]
+                                    {
+                                        new OsuSpriteText
+                                        {
+                                            Anchor = Anchor.Centre,
+                                            Origin = Anchor.Centre,
+                                            Text = "Apply this change to all difficulties?",
+                                            Margin = new MarginPadding { Bottom = 20f },
+                                        },
+                                        new RoundedButton
+                                        {
+                                            Anchor = Anchor.Centre,
+                                            Origin = Anchor.Centre,
+                                            Width = 300f,
+                                            Text = "Apply to all difficulties",
+                                            Action = () => ApplyToAllDifficulties.Value = true,
+                                            BackgroundColour = colours.Red2,
+                                        },
+                                        new RoundedButton
+                                        {
+                                            Anchor = Anchor.Centre,
+                                            Origin = Anchor.Centre,
+                                            Width = 300f,
+                                            Text = "Only apply to this difficulty",
+                                            Action = () => ApplyToAllDifficulties.Value = false,
+                                        },
+                                    }
+                                }
+                            }
+                        },
+                    }
+                });
+            }
+
+            protected override void LoadComplete()
+            {
+                base.LoadComplete();
+                ApplyToAllDifficulties.ValueChanged += onChangeScopeSelected;
+            }
+
+            protected override void OnFileSelected(FileInfo file)
+            {
+                if (multipleDifficulties)
+                    changeScopeContainer.FadeIn(200, Easing.InQuint);
+                else
+                    base.OnFileSelected(file);
+            }
+
+            private void onChangeScopeSelected(ValueChangedEvent<bool?> c)
+            {
+                if (c.NewValue == null)
+                    return;
+
+                Debug.Assert(FileSelector.CurrentFile.Value != null);
+                base.OnFileSelected(FileSelector.CurrentFile.Value);
+            }
+        }
+    }
+}