return ToolState and start switching tools

Program.cs

@@ -52,9 +52,15 @@ public class CameraInfo {
   public static readonly CameraInfo IPHONE_12_MINI = new(new Vector2i(4032, 3024));
 }
 
+public enum ToolState {
+  Active,
+  Done,
+  Canceled
+}
+
 public interface ITool {
   void SetActivePhoto(Photo photo);
-  void HandleInput(UiGeometry geometry, KeyboardState input, MouseState mouse, Game game);
+  ToolState HandleInput(UiGeometry geometry, KeyboardState input, MouseState mouse, Game game);
   string Status();
   void Draw(UiGeometry geometry, Game game);
 }
@@ -66,29 +72,32 @@ public class ViewTool : ITool {
     activePhoto = photo;
   }
 
-  public void HandleInput(UiGeometry geometry, KeyboardState input, MouseState mouse, Game game) {
+  public ToolState HandleInput(UiGeometry geometry, KeyboardState input, MouseState mouse, Game game) {
+    return ToolState.Active;
   }
 
   public string Status() {
-    return "";
+    return "view";
   }
 
   public void Draw(UiGeometry geometry, Game game) {
   }
 }
 
+
 // FIXME: remove unneeded dependencies on "Game" or at least refactor them a bit.
 public class CropTool : ITool {
 
   Photo? activePhoto;
   Vector2i mouseDragStart;
   Vector2i mouseDragEnd;
+  string status = "";
 
   public void SetActivePhoto(Photo photo) {
     activePhoto = photo;
   }
 
-  public void HandleInput(UiGeometry geometry, KeyboardState input, MouseState mouse, Game game) {
+  public ToolState HandleInput(UiGeometry geometry, KeyboardState input, MouseState mouse, Game game) {
     Vector2i mousePosition = (Vector2i) mouse.Position;
 
     if (mouse.IsButtonPressed(MouseButton.Button1)) {
@@ -104,15 +113,23 @@ public class CropTool : ITool {
       }
     }
 
-    if (input.IsKeyPressed(Keys.Escape)) {
-      mouseDragStart = new(-1, -1);
-      mouseDragEnd = new(-1, -1);
-    }
+    Vector2i start = game.ScreenToImage(mouseDragStart);
+    // FIXME: this needs to be the actual width of the computed box.
+    Vector2i size = game.ScreenToImage(mouseDragEnd) - start;
+
+    status = $"({start.X}, {start.Y}) {size.X}x{size.Y}";
 
-    // FIXME: crop should be a modal tool that starts with C and ends with Enter or Escape.
     if (input.IsKeyPressed(Keys.Enter)) {
       ApplyCrop(game);
+      return ToolState.Done;
+    }
+
+    if (input.IsKeyPressed(Keys.Escape)) {
+      activePhoto.CropRectangle = Rectangle.Empty;
+      return ToolState.Canceled;
     }
+
+    return ToolState.Active;
   }
 
   // left, right, top, bottom
@@ -171,7 +188,7 @@ public class CropTool : ITool {
   }
 
   public string Status() {
-    return "crop";
+    return "[crop] " + status;
   }
 }
 
@@ -754,7 +771,9 @@ public static class Util {
 }
 
 public class Game : GameWindow {
-  public Game(GameWindowSettings gwSettings, NativeWindowSettings nwSettings) : base(gwSettings, nwSettings) {}
+  public Game(GameWindowSettings gwSettings, NativeWindowSettings nwSettings) : base(gwSettings, nwSettings) {
+    activeTool = viewTool;
+  }
 
   private static string outputRoot = @"c:\users\colin\desktop\totte-output";
   // private static string outputRoot = @"c:\users\colin\pictures\photos";
@@ -785,7 +804,8 @@ public class Game : GameWindow {
   HashSet<Photo> loadedImages = new();
   HashSet<Photo> loadingImages = new();
   readonly object loadedImagesLock = new();
-  ITool activeTool = new CropTool();
+  readonly ViewTool viewTool = new ViewTool();
+  ITool activeTool;
   int photoIndex = 0;
   int ribbonIndex = 0;
   Vector2i mousePosition;
@@ -951,8 +971,21 @@ public class Game : GameWindow {
       zoomLevel = 16f;
     }
 
+    // Handle tool switching.
+    if (activeTool == viewTool) {
+      if (input.IsKeyPressed(Keys.C)) {
+        activeTool = new CropTool();
+      }
+    }
+
+    // Delegate input to the active tool.
     activeTool.SetActivePhoto(photos[photoIndex]);
-    activeTool.HandleInput(geometry, KeyboardState, MouseState, this);
+    ToolState state = activeTool.HandleInput(geometry, KeyboardState, MouseState, this);
+
+    // Change back to the default tool if the active tool is done.
+    if (state != ToolState.Active) {
+      activeTool = viewTool;
+    }
   }
 
   void FilterByRating(int rating) {
@@ -1186,15 +1219,13 @@ public class Game : GameWindow {
     if (activePhoto.Loaded) {
       DrawText($"{(scale * 100):F1}%", geometry.StatusBox.Min.X, y);
     }
-    DrawText($"({mousePosition.X}, {mousePosition.Y})", geometry.StatusBox.Min.X + 72, y);
-    Vector2i imagePosition = ScreenToImage(mousePosition);
-    DrawText($"({imagePosition.X}, {imagePosition.Y})", geometry.StatusBox.Min.X + 320, y);
+    DrawText(activeTool.Status(), geometry.StatusBox.Min.X + 72, y);
   }
 
   public Vector2i ScreenToImage(int x, int y) {
-    return new(
-        (int) ((x - activeOffset.X) / activeScale),
-        (int) ((y - activeOffset.Y) / activeScale));
+    int rx = (int) ((x - activeOffset.X) / activeScale);
+    int ry = (int) ((y - activeOffset.Y) / activeScale);
+    return new(rx, ry);
   }
 
   public Vector2i ScreenToImage(Vector2i position) {