From 04a472121e80fb8f98e5785b0d43cdc2d0eda7ea Mon Sep 17 00:00:00 2001
From: Sergey Yagovtsev <yse.sey@gmail.com>
Date: Mon, 13 Nov 2023 23:49:13 +0300
Subject: [PATCH] #210 Safety range for GraphicsBlockItem intersection

---
 profiler_gui/graphics_block_item.cpp | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/profiler_gui/graphics_block_item.cpp b/profiler_gui/graphics_block_item.cpp
index f8d322c..06f1e1f 100644
--- a/profiler_gui/graphics_block_item.cpp
+++ b/profiler_gui/graphics_block_item.cpp
@@ -1271,9 +1271,26 @@ const ::profiler_gui::EasyBlock* GraphicsBlockItem::intersect(const QPointF& _po
     while (i <= levelIndex)
     {
         const auto& level = m_levels[i];
+        size_t levelSize = level.size();
+
+        auto firstItemIterator = level.begin();
+        auto lastItemIterator = level.begin();
+
+        // Ensure that firstItem and lastItem are within the permissible range
+        if (firstItem < levelSize) {
+            std::advance(firstItemIterator, firstItem);
+        } else {
+            firstItemIterator = level.end();
+        }
+
+        if (lastItem <= levelSize) {
+            std::advance(lastItemIterator, lastItem);
+        } else {
+            lastItemIterator = level.end();
+        }
 
         // Search for first visible item
-        auto first = ::std::lower_bound(level.begin() + firstItem, level.begin() + lastItem, _pos.x(), [](const ::profiler_gui::EasyBlockItem& _item, qreal _value)
+        auto first = ::std::lower_bound(firstItemIterator, lastItemIterator, _pos.x(), [](const ::profiler_gui::EasyBlockItem& _item, qreal _value)
         {
             return _item.left() < _value;
         });