adding validated services? patching forcad_local.py

OmCTF-2025/services/block_game/backend/utils/xy/xy.go

@@ -0,0 +1,40 @@
+package xy
+
+import (
+	"fmt"
+)
+
+type Point struct {
+	X int `json:"x"`
+	Y int `json:"y"`
+}
+
+func (p Point) Go(dir Direction) (Point, error) {
+	switch dir {
+	case Up:
+		return Point{X: p.X, Y: p.Y - 1}, nil
+	case Down:
+		return Point{X: p.X, Y: p.Y + 1}, nil
+	case Left:
+		return Point{X: p.X - 1, Y: p.Y}, nil
+	case Right:
+		return Point{X: p.X + 1, Y: p.Y}, nil
+	}
+	return p, fmt.Errorf("invalid direction: %s", dir)
+}
+
+type Direction string
+
+const (
+	Up    Direction = "up"
+	Down  Direction = "down"
+	Left  Direction = "left"
+	Right Direction = "right"
+)
+
+func (d Direction) Validate() error {
+	if d == Up || d == Down || d == Left || d == Right {
+		return nil
+	}
+	return fmt.Errorf("invalid direction: %s (out of %v)", d, []Direction{Up, Down, Left, Right})
+}