Add History to Memory Viewer

src/ui/viewmodels/MemoryViewerViewModel.cpp

@@ -23,6 +23,7 @@ constexpr uint8_t HIGHLIGHTED_COLOR = STALE_COLOR | gsl::narrow_cast<uint8_t>(ra
 constexpr int ADDRESS_COLUMN_WIDTH = 10;
 constexpr int BASE_MEMORY_VIEWER_WIDTH_IN_CHARACTERS =
     (ADDRESS_COLUMN_WIDTH + 16 * 3 - 1); // address column + 16 bytes "XX " - last space
+constexpr int MEMVIEW_HISTORY_MAX_SIZE = 50;
 
 std::unique_ptr<ra::ui::drawing::ISurface> MemoryViewerViewModel::s_pFontSurface;
 std::unique_ptr<ra::ui::drawing::ISurface> MemoryViewerViewModel::s_pFontASCIISurface;
@@ -94,6 +95,8 @@ class MemoryViewerViewModel::MemoryBookmarkMonitor : protected ViewModelCollecti
 private:
     ViewModelCollection<ra::ui::viewmodels::MemoryBookmarksViewModel::MemoryBookmarkViewModel>& m_vBookmarks;
     MemoryViewerViewModel& m_pOwner;
+    std::vector<ra::ByteAddress> vHistory;
+    std::vector<ra::ByteAddress>::iterator iterHistoryIndex;
 };
 
 MemoryViewerViewModel::MemoryViewerViewModel()
@@ -110,6 +113,9 @@ MemoryViewerViewModel::MemoryViewerViewModel()
 
     m_pInvalid = m_pMemory + MaxLines * 16 * 2;
     memset(m_pInvalid, 0, MaxLines * 16);
+
+    vHistory = {0};
+    iterHistoryIndex = vHistory.begin();
 }
 
 void MemoryViewerViewModel::InitializeNotifyTargets()
@@ -366,6 +372,8 @@ void MemoryViewerViewModel::SetAddress(ra::ByteAddress nValue)
     {
         SetValue(PendingAddressProperty, gsl::narrow_cast<int>(nValue));
     }
+
+    AddToHistory(nValue);
 }
 
 void MemoryViewerViewModel::SetFirstAddress(ra::ByteAddress value)
@@ -666,6 +674,8 @@ void MemoryViewerViewModel::OnActiveGameChanged()
 
     const auto& pGameContext = ra::services::ServiceLocator::Get<ra::data::context::GameContext>();
     m_bReadOnly = (pGameContext.GameId() == 0);
+
+    ClearHistory();
 }
 
 void MemoryViewerViewModel::OnCodeNoteChanged(ra::ByteAddress nAddress, const std::wstring& sNote)
@@ -1314,6 +1324,40 @@ void MemoryViewerViewModel::RenderHeader()
     }
 }
 
+void MemoryViewerViewModel::AddToHistory(ra::ByteAddress nAddress)
+{
+    if (*iterHistoryIndex != nAddress)
+    {
+        vHistory.erase(iterHistoryIndex + 1, vHistory.end());
+        if (vHistory.size() == MEMVIEW_HISTORY_MAX_SIZE)
+            vHistory.erase(vHistory.begin());
+        vHistory.push_back(nAddress);
+        iterHistoryIndex = vHistory.end() - 1;
+    }
+}
+
+void MemoryViewerViewModel::ClearHistory()
+{
+    vHistory.erase(vHistory.begin(), vHistory.end());
+    vHistory.push_back(0);
+    iterHistoryIndex = vHistory.begin();
+}
+
+void MemoryViewerViewModel::MoveHistoryForward()
+{
+    int nIndex = std::distance(vHistory.begin(), iterHistoryIndex);
+    if (vHistory.size() > (nIndex + 1))
+        ++iterHistoryIndex;
+    SetAddress(*iterHistoryIndex);
+}
+
+void MemoryViewerViewModel::MoveHistoryBackward()
+{
+    if (vHistory.size() >= 1 and iterHistoryIndex != vHistory.begin())
+        --iterHistoryIndex;
+    SetAddress(*iterHistoryIndex);
+}
+
 } // namespace viewmodels
 } // namespace ui
 } // namespace ra

src/ui/viewmodels/MemoryViewerViewModel.hh

@@ -175,6 +175,11 @@ public:
     void AdvanceCursorPage();
     void RetreatCursorPage();
 
+    void AddToHistory(ra::ByteAddress nAddress);
+    void ClearHistory();
+    void MoveHistoryBackward();
+    void MoveHistoryForward();
+
 protected:
     void OnValueChanged(const IntModelProperty::ChangeArgs& args) override;
 
@@ -206,6 +211,8 @@ protected:
     static constexpr int REDRAW_ALL = REDRAW_MEMORY | REDRAW_ADDRESSES | REDRAW_HEADERS;
     int m_nNeedsRedraw = REDRAW_ALL;
 
+
+
     static constexpr int MaxLines = 128;
 
 private:
@@ -239,6 +246,9 @@ private:
     class MemoryBookmarkMonitor;
     friend class MemoryBookmarkMonitor;
     std::unique_ptr<MemoryBookmarkMonitor> m_pBookmarkMonitor;
+
+    std::vector<ra::ByteAddress> vHistory;
+    std::vector<ra::ByteAddress>::iterator iterHistoryIndex;
 };
 
 } // namespace viewmodels

src/ui/win32/bindings/MemoryViewerControlBinding.cpp

@@ -57,6 +57,13 @@ INT_PTR CALLBACK MemoryViewerControlBinding::WndProc(HWND hControl, UINT uMsg, W
         case WM_USER_INVALIDATE:
             Invalidate();
             return FALSE;
+
+        case WM_XBUTTONUP:
+            if (GET_XBUTTON_WPARAM(wParam) == XBUTTON1)
+                m_pViewModel.MoveHistoryBackward();
+            else if (GET_XBUTTON_WPARAM(wParam) == XBUTTON2)
+                m_pViewModel.MoveHistoryForward();
+            return FALSE;
     }
 
     return ControlBinding::WndProc(hControl, uMsg, wParam, lParam);

tests/ui/viewmodels/MemoryViewerViewModel_Tests.cpp

@@ -1918,6 +1918,54 @@ TEST_CLASS(MemoryViewerViewModel_Tests)
         Assert::IsTrue(viewer.NeedsRedraw());
         viewer.MockRender();
     }
+    TEST_METHOD(TestOnMoveHistory)
+    {
+        MemoryViewerViewModelHarness viewer;
+        viewer.InitializeMemory(256);
+
+        viewer.SetAddress(0U);
+        viewer.SetReadOnly(false);
+
+        // Step backward one time should do nothing as it's the first move
+        viewer.MoveHistoryBackward();
+        Assert::AreEqual({0U}, viewer.GetAddress());
+
+        // Move to 0x1 and step backward should lead to address 0x0
+        viewer.SetAddress(1U);
+        viewer.MoveHistoryBackward();
+        Assert::AreEqual({0U}, viewer.GetAddress());
+
+        // Move one step forward should lead to address 0x1
+        viewer.MoveHistoryForward();
+        Assert::AreEqual({1U}, viewer.GetAddress());
+
+        // Move to 0x1 then to 0x2 and finally to 0x3 and step backward one time should lead to address 0x2
+        viewer.SetAddress(1U);
+        viewer.SetAddress(2U);
+        viewer.SetAddress(3U);
+        viewer.MoveHistoryBackward();
+        Assert::AreEqual({2U}, viewer.GetAddress());
+
+        // Move two steps forward should lead to address 0x3 as it's the most recent history entry
+        viewer.MoveHistoryForward();
+        viewer.MoveHistoryForward();
+        Assert::AreEqual({3U}, viewer.GetAddress());
+
+        // Three last steps backward and we are back to square one at address 0x0
+        viewer.MoveHistoryBackward();
+        viewer.MoveHistoryBackward();
+        viewer.MoveHistoryBackward();
+        Assert::AreEqual({0U}, viewer.GetAddress());
+
+        // Change game to clear history
+        viewer.mockGameContext.NotifyActiveGameChanged();
+
+        // Move three steps forward to get back to 0x3 should do nothing as the game changed and history got cleared
+        viewer.MoveHistoryForward();
+        viewer.MoveHistoryForward();
+        viewer.MoveHistoryForward();
+        Assert::AreEqual({0U}, viewer.GetAddress());
+    }
 };
 
 } // namespace tests