From ac728708943bc5b5c9a2650a51f250c401820667 Mon Sep 17 00:00:00 2001
From: Xavier Fontanet <xavier.fontanet@edreamsodigeo.com>
Date: Thu, 20 Jun 2024 23:06:19 +0200
Subject: [PATCH] also in backwards

---
 .../java/cat/hack3/codingtests/marsrover/MarsMap.java | 11 ++++++++---
 .../hack3/codingtests/marsrover/MarsRoverTest.java    | 11 +++++++++++
 2 files changed, 19 insertions(+), 3 deletions(-)

diff --git a/src/main/java/cat/hack3/codingtests/marsrover/MarsMap.java b/src/main/java/cat/hack3/codingtests/marsrover/MarsMap.java
index 617ac5b..3650405 100644
--- a/src/main/java/cat/hack3/codingtests/marsrover/MarsMap.java
+++ b/src/main/java/cat/hack3/codingtests/marsrover/MarsMap.java
@@ -65,11 +65,16 @@ public class MarsMap {
         setNewLongitude(newLongitude);
     }
 
-    private void setNewLongitude(int newLongitude) {
-        currentPosition = currentPosition.ofUpdatedLongitude(newLongitude);
+    private void decrementLongitude() {
+        int longitude = currentPosition.getLongitude();
+        int newLongitude = longitude - 1 < 1
+                ? width
+                : --longitude;
+        setNewLongitude(newLongitude);
     }
 
-    private void decrementLongitude() {
+    private void setNewLongitude(int newLongitude) {
+        currentPosition = currentPosition.ofUpdatedLongitude(newLongitude);
     }
 
     public Coordinates getCurrentPosition() {
diff --git a/src/test/java/cat/hack3/codingtests/marsrover/MarsRoverTest.java b/src/test/java/cat/hack3/codingtests/marsrover/MarsRoverTest.java
index 66fcaee..3edd633 100644
--- a/src/test/java/cat/hack3/codingtests/marsrover/MarsRoverTest.java
+++ b/src/test/java/cat/hack3/codingtests/marsrover/MarsRoverTest.java
@@ -95,6 +95,17 @@ public class MarsRoverTest {
         assertEquals(rover.getCurrentDirection(), EAST);
     }
 
+    @Test
+    public void loopTheWorldInLongitudeMovingBackwards() {
+        Coordinates originalCoordinates = rover.getCurrentCoordinates();
+
+        rover.turnLeft();
+        repeatAction(10, i -> rover.moveBackwards());
+
+        assertEquals(rover.getCurrentCoordinates(), originalCoordinates);
+        assertEquals(rover.getCurrentDirection(), EAST);
+    }
+
     private void repeatAction(int times, IntConsumer actionToRepeat) {
         IntStream.rangeClosed(1, times)
                 .forEach(actionToRepeat);