notification: Switch to CircularBuffer for notification buffer

Author: FintasticMan

src/components/ble/NotificationManager.cpp

@@ -11,13 +11,9 @@ void NotificationManager::Push(NotificationManager::Notification&& notif) {
   notif.id = GetNextId();
   notif.valid = true;
   newNotification = true;
-  if (beginIdx > 0) {
-    --beginIdx;
-  } else {
-    beginIdx = notifications.size() - 1;
-  }
-  notifications[beginIdx] = std::move(notif);
-  if (size < notifications.size()) {
+  notifications--;
+  notifications[0] = std::move(notif);
+  if (size < notifications.Size()) {
     size++;
   }
 }
@@ -30,30 +26,12 @@ NotificationManager::Notification NotificationManager::GetLastNotification() con
   if (this->IsEmpty()) {
     return {};
   }
-  return this->At(0);
-}
-
-const NotificationManager::Notification& NotificationManager::At(NotificationManager::Notification::Idx idx) const {
-  if (idx >= notifications.size()) {
-    assert(false);
-    return notifications.at(beginIdx); // this should not happen
-  }
-  size_t read_idx = (beginIdx + idx) % notifications.size();
-  return notifications.at(read_idx);
-}
-
-NotificationManager::Notification& NotificationManager::At(NotificationManager::Notification::Idx idx) {
-  if (idx >= notifications.size()) {
-    assert(false);
-    return notifications.at(beginIdx); // this should not happen
-  }
-  size_t read_idx = (beginIdx + idx) % notifications.size();
-  return notifications.at(read_idx);
+  return notifications[0];
 }
 
 NotificationManager::Notification::Idx NotificationManager::IndexOf(NotificationManager::Notification::Id id) const {
   for (NotificationManager::Notification::Idx idx = 0; idx < this->size; idx++) {
-    const NotificationManager::Notification& notification = this->At(idx);
+    const NotificationManager::Notification& notification = notifications[idx];
     if (notification.id == id) {
       return idx;
     }
@@ -66,29 +44,29 @@ NotificationManager::Notification NotificationManager::Get(NotificationManager::
   if (idx == this->size) {
     return {};
   }
-  return this->At(idx);
+  return notifications[idx];
 }
 
 NotificationManager::Notification NotificationManager::GetNext(NotificationManager::Notification::Id id) const {
   NotificationManager::Notification::Idx idx = this->IndexOf(id);
   if (idx == this->size) {
     return {};
   }
-  if (idx == 0 || idx > notifications.size()) {
+  if (idx == 0 || idx > notifications.Size()) {
     return {};
   }
-  return this->At(idx - 1);
+  return notifications[idx - 1];
 }
 
 NotificationManager::Notification NotificationManager::GetPrevious(NotificationManager::Notification::Id id) const {
   NotificationManager::Notification::Idx idx = this->IndexOf(id);
   if (idx == this->size) {
     return {};
   }
-  if (static_cast<size_t>(idx + 1) >= notifications.size()) {
+  if (idx + 1u >= notifications.Size()) {
     return {};
   }
-  return this->At(idx + 1);
+  return notifications[idx + 1];
 }
 
 void NotificationManager::DismissIdx(NotificationManager::Notification::Idx idx) {
@@ -100,14 +78,14 @@ void NotificationManager::DismissIdx(NotificationManager::Notification::Idx idx)
     return; // this should not happen
   }
   if (idx == 0) { // just remove the first element, don't need to change the other elements
-    notifications.at(beginIdx).valid = false;
-    beginIdx = (beginIdx + 1) % notifications.size();
+    notifications[0].valid = false;
+    notifications++;
   } else {
     // overwrite the specified entry by moving all later messages one index to the front
     for (size_t i = idx; i < size - 1; ++i) {
-      this->At(i) = this->At(i + 1);
+      notifications[i] = notifications[i + 1];
     }
-    this->At(size - 1).valid = false;
+    notifications[size - 1].valid = false;
   }
   --size;
 }

src/components/ble/NotificationManager.h

@@ -5,6 +5,8 @@
 #include <cstddef>
 #include <cstdint>
 
+#include "utility/CircularBuffer.h"
+
 namespace Pinetime {
   namespace Controllers {
     class NotificationManager {
@@ -61,14 +63,10 @@ namespace Pinetime {
     private:
       Notification::Id nextId {0};
       Notification::Id GetNextId();
-      const Notification& At(Notification::Idx idx) const;
-      Notification& At(Notification::Idx idx);
       void DismissIdx(Notification::Idx idx);
 
-      static constexpr uint8_t TotalNbNotifications = 5;
-      std::array<Notification, TotalNbNotifications> notifications;
-      size_t beginIdx = TotalNbNotifications - 1; // index of the newest notification
-      size_t size = 0;                            // number of valid notifications in buffer
+      Utility::CircularBuffer<Notification, 5> notifications;
+      size_t size = 0; // number of valid notifications in buffer
 
       std::atomic<bool> newNotification {false};
     };