1 files changed, 79 insertions, 0 deletions

diff --git a/src/ch/epfl/maze/util/Trail.java b/src/ch/epfl/maze/util/Trail.java
new file mode 100644
index 0000000..351db8f
--- /dev/null
+++ b/src/ch/epfl/maze/util/Trail.java
@@ -0,0 +1,79 @@
+package ch.epfl.maze.util;
+
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * A trail keeping track on positional markings.
+ *
+ * @author Pacien TRAN-GIRARD
+ */
+public class Trail {
+
+    public enum Marking {
+        NO_MARKING,
+        AVOID_MARKING,
+        NO_GO_MARKING;
+
+        public static Marking DEFAULT = NO_MARKING;
+        public static Marking[] ALL = new Marking[]{NO_MARKING, AVOID_MARKING, NO_GO_MARKING};
+
+        /**
+         * Returns the next Marking.
+         *
+         * @return The next Marking
+         */
+        public Marking getNext() {
+            switch (this) {
+                case NO_MARKING:
+                    return AVOID_MARKING;
+                case AVOID_MARKING:
+                    return NO_GO_MARKING;
+                case NO_GO_MARKING:
+                    return NO_GO_MARKING;
+                default:
+                    return AVOID_MARKING;
+            }
+        }
+    }
+
+    private final Map<Vector2D, Marking> trail;
+
+    /**
+     * Constructs a new blank Trail.
+     */
+    public Trail() {
+        this.trail = new HashMap<>();
+    }
+
+    /**
+     * Get the marking at the given position.
+     *
+     * @param position The positional Vector
+     * @return The Marking
+     */
+    public Marking getMarking(Vector2D position) {
+        Marking marking = this.trail.get(position);
+        return marking != null ? marking : Marking.DEFAULT;
+    }
+
+    /**
+     * Marks the given position with the given Marking.
+     *
+     * @param position The positional vector
+     * @param marking  The Marking
+     */
+    public void markPosition(Vector2D position, Marking marking) {
+        this.trail.put(position, marking);
+    }
+
+    /**
+     * Marks the given position with the following Marking.
+     *
+     * @param position The positional vector
+     */
+    public void markPosition(Vector2D position) {
+        this.markPosition(position, this.getMarking(position).getNext());
+    }
+
+}