From 6358a8f3c876b3a43c1c7189dd3890eef5895ddf Mon Sep 17 00:00:00 2001
From: Lev Dragunov <l.dragunov@corp.mail.ru>
Date: Thu, 21 Jan 2016 13:43:45 +0300
Subject: [PATCH] Review fixes.

---
 .../osrm-backend/plugins/MapsMePlugin.hpp     | 104 +++++++++++-------
 1 file changed, 62 insertions(+), 42 deletions(-)

diff --git a/3party/osrm/osrm-backend/plugins/MapsMePlugin.hpp b/3party/osrm/osrm-backend/plugins/MapsMePlugin.hpp
index 5bfacc713f..4cb6e5d05b 100644
--- a/3party/osrm/osrm-backend/plugins/MapsMePlugin.hpp
+++ b/3party/osrm/osrm-backend/plugins/MapsMePlugin.hpp
@@ -29,7 +29,61 @@
 #include <string>
 #include <vector>
 
-double constexpr kMaxDistanceToFindMeters = 1000.0;
+using TMapRepr = pair<size_t, m2::PointD>;
+
+class UsedMwmChecker
+{
+public:
+  static size_t constexpr kInvalidIndex = numeric_limits<size_t>::max();
+
+  UsedMwmChecker() : m_lastUsedMwm(kInvalidIndex) {}
+
+  void AddPoint(size_t mwmIndex, m2::PointD const & pt)
+  {
+    if (mwmIndex == kInvalidIndex)
+      return;
+    if (mwmIndex != m_lastUsedMwm)
+    {
+      CommitUsedPoints();
+      m_lastUsedMwm = mwmIndex;
+    }
+    m_lastMwmPoints.push_back(pt);
+  }
+
+  vector<TMapRepr> const & GetUsedMwms()
+  {
+    // Get point from the last mwm.
+    CommitUsedPoints();
+
+    std::sort(m_usedMwms.begin(), m_usedMwms.end(), []
+              (TMapRepr const & a, TMapRepr const & b)
+              {
+                return a.first < b.first;
+              });
+    auto const it = std::unique(m_usedMwms.begin(), m_usedMwms.end(), []
+                                (TMapRepr const & a, TMapRepr const & b)
+                                {
+                                    return a.first == b.first;
+                                });
+    m_usedMwms.erase(it, m_usedMwms.end());
+    return m_usedMwms;
+  }
+
+private:
+  void CommitUsedPoints()
+  {
+    if (!m_lastMwmPoints.empty() && m_lastUsedMwm != kInvalidIndex)
+    {
+      size_t delta = m_lastMwmPoints.size() / 2;
+      m_usedMwms.emplace_back(m_lastUsedMwm, m_lastMwmPoints[delta]);
+    }
+    m_lastMwmPoints.clear();
+  }
+
+  vector<TMapRepr> m_usedMwms;
+  size_t m_lastUsedMwm;
+  vector<m2::PointD> m_lastMwmPoints;
+};
 
 template <class DataFacadeT> class MapsMePlugin final : public BasePlugin
 {
@@ -107,6 +161,8 @@ public:
 
     int HandleRequest(const RouteParameters &route_parameters, osrm::json::Object &reply) override final
     {
+        double constexpr kMaxDistanceToFindMeters = 1000.0;
+
         //We process only two points case
         if (route_parameters.coordinates.size() != 2)
             return 400;
@@ -123,7 +179,8 @@ public:
             std::vector<std::pair<PhantomNode, double>> phantom_node_vector;
             //FixedPointCoordinate &coordinate = route_parameters.coordinates[i];
             if (m_facade->IncrementalFindPhantomNodeForCoordinateWithMaxDistance(route_parameters.coordinates[i],
-                                                                                 phantom_node_vector, kMaxDistanceToFindMeters, 0, 2))
+                                                                                 phantom_node_vector, kMaxDistanceToFindMeters,
+                                                                                 0 /*min_number_of_phantom_nodes*/, 2 /*max_number_of_phantom_nodes*/))
             {
                 BOOST_ASSERT(!phantom_node_vector.empty());
                 // Don't know why, but distance may be higher that maxDistance.
@@ -194,9 +251,7 @@ public:
             return 400;
         }
         // Get mwm names
-        vector<pair<size_t, m2::PointD>> usedMwms;
-        size_t lastUsedMwm = numeric_limits<size_t>::max();
-        vector<m2::PointD> mwmPoints;
+        UsedMwmChecker usedChecker;
 
         for (auto i : osrm::irange<std::size_t>(0, raw_route.unpacked_path_segments.size()))
         {
@@ -211,47 +266,12 @@ public:
                 m2::PointD pt = MercatorBounds::FromLatLon(seg.lat1, seg.lon1);
                 GetByPoint doGet(m_regions, pt);
                 ForEachCountry(pt, doGet);
-
-                auto const & index = doGet.m_res;
-                if (index == std::numeric_limits<size_t>::max())
-                  continue;
-
-                if (index != lastUsedMwm)
-                {
-                  if (!mwmPoints.empty())
-                  {
-                    // Get the middlest point (max far from borders).
-                    size_t delta = std::distance(mwmPoints.begin(), mwmPoints.end()) / 2;
-                    usedMwms.emplace_back(lastUsedMwm, mwmPoints[delta]);
-                    mwmPoints.clear();
-                  }
-                  lastUsedMwm = index;
-                }
-                mwmPoints.push_back(pt);
+                usedChecker.AddPoint(doGet.m_res, pt);
             }
         }
-        // Get point from last mwm.
-        if (!mwmPoints.empty())
-        {
-          size_t delta = std::distance(mwmPoints.begin(), mwmPoints.end()) / 2;
-          usedMwms.emplace_back(lastUsedMwm, mwmPoints[delta]);
-          mwmPoints.clear();
-        }
-
-        std::sort(usedMwms.begin(), usedMwms.end(), []
-                  (pair<size_t, m2::PointD> const & a, pair<size_t, m2::PointD> const & b)
-                  {
-                    return a.first < b.first;
-                  });
-        auto const it = std::unique(usedMwms.begin(), usedMwms.end(), []
-                                    (pair<size_t, m2::PointD> const & a, pair<size_t, m2::PointD> const & b)
-                                    {
-                                        return a.first == b.first;
-                                    });
-        usedMwms.erase(it, usedMwms.end());
 
         osrm::json::Array json_array;
-        for (auto & mwm : usedMwms)
+        for (auto & mwm : usedChecker.GetUsedMwms())
         {
             osrm::json::Array pointArray;
             pointArray.values.push_back(mwm.second.x);