2 files changed, 12 insertions, 20 deletions
diff --git a/src/components/stopwatch/StopWatchController.cpp b/src/components/stopwatch/StopWatchController.cpp
index f9709e6b..d8e48588 100644
--- a/src/components/stopwatch/StopWatchController.cpp
+++ b/src/components/stopwatch/StopWatchController.cpp
@@ -27,35 +27,26 @@ void StopWatchController::Clear() {
     laps[i].time = 0;
   }
   lapCount = 0;
-  lapHead = 0;
 }
 
 // Lap
 
 void StopWatchController::PushLap() {
   TickType_t lapEnd = GetElapsedTime();
-  laps[lapHead].time = lapEnd;
-  laps[lapHead].count = lapCount + 1;
-  lapCount += 1;
-  lapHead = lapCount % lapCapacity;
+  laps[0].time = lapEnd;
+  laps[0].count = ++lapCount;
+  laps--;
 }
 
 int StopWatchController::GetLapCount() {
   return lapCount;
 }
 
-int Wrap(int index) {
-  return ((index % lapCapacity) + lapCapacity) % lapCapacity;
-}
-
 std::optional<LapInfo> StopWatchController::LastLap(int lap) {
-  if (lap >= lapCapacity || lap >= lapCount) {
+  if (lap < 0 || lap >= lapCapacity || laps[lap].count == 0) {
     return {};
   }
-  // Index backwards
-  int mostRecentLap = lapHead - 1;
-  int index = Wrap(mostRecentLap - lap);
-  return laps[index];
+  return laps[lap];
 }
 
 // Data / State acess
diff --git a/src/components/stopwatch/StopWatchController.h b/src/components/stopwatch/StopWatchController.h
index c549a71e..626f214f 100644
--- a/src/components/stopwatch/StopWatchController.h
+++ b/src/components/stopwatch/StopWatchController.h
@@ -3,6 +3,7 @@
 #include <FreeRTOS.h>
 #include <optional>
 #include <timers.h>
+#include "utility/CircularBuffer.h"
 
 namespace Pinetime {
   namespace System {
@@ -17,7 +18,6 @@ namespace Pinetime {
       TickType_t time = 0; // Delta time from beginning of stopwatch
     };
 
-    constexpr int lapCapacity = 2;
 
     class StopWatchController {
     public:
@@ -45,19 +45,20 @@ namespace Pinetime {
       bool IsCleared();
       bool IsPaused();
 
-    // private:
+    private:
       // Current state of stopwatch
       StopWatchStates currentState = StopWatchStates::Cleared;
       // Start time of current duration
       TickType_t startTime = 0;
       // How much time was elapsed before current duration
       TickType_t timeElapsedPreviously = 0;
-      // Stores lap times
-      LapInfo laps[lapCapacity];
+
+      // Number of stored laps
+      static constexpr int lapCapacity = 2;
+      // Lap storage
+      Utility::CircularBuffer<LapInfo, lapCapacity> laps;
       // Total lap count; may exceed lapCapacity
       int lapCount = 0;
-      // Index for next lap time; must be lower than lapCapacity
-      int lapHead = 0;
     };
   }
 }