From ef806cf18a33fd6be59ebf1dda4772637237e5c8 Mon Sep 17 00:00:00 2001
From: mvglasow <michael -at- vonglasow.com>
Date: Thu, 28 Aug 2025 21:10:42 +0300
Subject: [PATCH] Synchronize map updates with traffic manager

Signed-off-by: mvglasow <michael -at- vonglasow.com>
---
 map/framework.cpp       | 14 ++++----
 map/traffic_manager.cpp | 78 +++++++++++++++++++----------------------
 map/traffic_manager.hpp | 16 +++++++++
 3 files changed, 60 insertions(+), 48 deletions(-)

diff --git a/map/framework.cpp b/map/framework.cpp
index 3ae4a917b..a3b37c201 100644
--- a/map/framework.cpp
+++ b/map/framework.cpp
@@ -443,13 +443,13 @@ void Framework::OnCountryFileDownloaded(storage::CountryId const &,
   m2::RectD rect = mercator::Bounds::FullRect();
 
   if (localFile && localFile->OnDisk(MapFileType::Map))
-  {
-    auto const res = RegisterMap(*localFile);
-    MwmSet::MwmId const & id = res.first;
-    if (id.IsAlive())
-      rect = id.GetInfo()->m_bordersRect;
-    m_trafficManager.Invalidate(id);
-  }
+    m_trafficManager.RunSynchronized([this, localFile, &rect](){
+      auto const res = RegisterMap(*localFile);
+      MwmSet::MwmId const & id = res.first;
+      if (id.IsAlive())
+        rect = id.GetInfo()->m_bordersRect;
+      m_trafficManager.Invalidate(id);
+    });
 
   m_transitManager.Invalidate();
   m_isolinesManager.Invalidate();
diff --git a/map/traffic_manager.cpp b/map/traffic_manager.cpp
index f365967bd..d3214d83c 100644
--- a/map/traffic_manager.cpp
+++ b/map/traffic_manager.cpp
@@ -301,53 +301,49 @@ void TrafficManager::Invalidate(MwmSet::MwmId const & mwmId)
   auto const mwmRect = mwmId.GetInfo()->m_bordersRect; // m2::RectD
   traffxml::TraffFeed invalidated;
 
+  for (auto it = m_messageCache.begin(); it != m_messageCache.end(); )
   {
-    std::lock_guard<std::mutex> lock(m_mutex);
-
-    for (auto it = m_messageCache.begin(); it != m_messageCache.end(); )
+    if (!it->second.m_location)
     {
-      if (!it->second.m_location)
-      {
-        it++;
-        continue;
-      }
-
-      bool isInvalid = false;
-
-      // invalidate if decoded location uses a previous version of the MWM
-      for (auto const & [decodedMwmId, coloring] : it->second.m_decoded)
-        if (decodedMwmId.GetInfo()->GetCountryName() == mwmId.GetInfo()->GetCountryName())
-          isInvalid = true;
-
-      // invalidate if bounding rect of reference points intersects with bounding rect of MWM
-      if (!isInvalid)
-      {
-        m2::RectD locationRect;
-        for (auto const & point : {it->second.m_location.value().m_from,
-                                   it->second.m_location.value().m_via,
-                                   it->second.m_location.value().m_at,
-                                   it->second.m_location.value().m_to})
-          if (point)
-            locationRect.Add(mercator::FromLatLon(point.value().m_coordinates));
-        isInvalid = locationRect.IsIntersect(mwmRect);
-      }
-
-      if (isInvalid)
-      {
-        traffxml::TraffMessage message(it->second);
-        message.m_decoded.clear();
-        invalidated.push_back(message);
-        it = m_messageCache.erase(it);
-      }
-      else
-        ++it;
+      it++;
+      continue;
     }
 
-    if (!invalidated.empty())
+    bool isInvalid = false;
+
+    // invalidate if decoded location uses a previous version of the MWM
+    for (auto const & [decodedMwmId, coloring] : it->second.m_decoded)
+      if (decodedMwmId.GetInfo()->GetCountryName() == mwmId.GetInfo()->GetCountryName())
+        isInvalid = true;
+
+    // invalidate if bounding rect of reference points intersects with bounding rect of MWM
+    if (!isInvalid)
     {
-      m_feedQueue.insert(m_feedQueue.begin(), invalidated);
-      m_condition.notify_one();
+      m2::RectD locationRect;
+      for (auto const & point : {it->second.m_location.value().m_from,
+           it->second.m_location.value().m_via,
+           it->second.m_location.value().m_at,
+           it->second.m_location.value().m_to})
+        if (point)
+          locationRect.Add(mercator::FromLatLon(point.value().m_coordinates));
+      isInvalid = locationRect.IsIntersect(mwmRect);
     }
+
+    if (isInvalid)
+    {
+      traffxml::TraffMessage message(it->second);
+      message.m_decoded.clear();
+      invalidated.push_back(message);
+      it = m_messageCache.erase(it);
+    }
+    else
+      ++it;
+  }
+
+  if (!invalidated.empty())
+  {
+    m_feedQueue.insert(m_feedQueue.begin(), invalidated);
+    m_condition.notify_one();
   }
 }
 
diff --git a/map/traffic_manager.hpp b/map/traffic_manager.hpp
index 8c24ec2f2..82b816faf 100644
--- a/map/traffic_manager.hpp
+++ b/map/traffic_manager.hpp
@@ -224,6 +224,9 @@ public:
    * for these locations are discarded and decoded again, ensuring they are based on the new MWM.
    * The TraFF messages themselves remain unchanged.
    *
+   * This method must either be called from a lambda function passed to `RunSynchronized()`,
+   * or the caller must explicitly lock the private `m_mutex` prior to calling this method.
+   *
    * @param mwmId The newly addded MWM.
    */
   void Invalidate(MwmSet::MwmId const & mwmId);
@@ -313,6 +316,19 @@ public:
    */
   void SetTrafficUpdateCallbackFn(TrafficUpdateCallbackFn && fn);
 
+  /**
+   * @brief Runs a function guarded by the traffic manager mutex.
+   *
+   * This locks `m_mutex`, then runs `f` and releases the mutex.
+   *
+   * @param f
+   */
+  void RunSynchronized(std::function<void()> f)
+  {
+    std::lock_guard<std::mutex> lock(m_mutex);
+    f();
+  }
+
 private:
 
   /**