Repo created

libs/search/locality_scorer.hpp

@@ -0,0 +1,82 @@
+#pragma once
+
+#include "search/cbv.hpp"
+#include "search/geocoder_locality.hpp"
+
+#include <limits>
+#include <optional>
+#include <string>
+#include <vector>
+
+namespace search
+{
+class CBV;
+class IdfMap;
+class QueryParams;
+struct BaseContext;
+
+class LocalityScorer
+{
+public:
+  class Delegate
+  {
+  public:
+    virtual ~Delegate() = default;
+
+    virtual void GetNames(uint32_t featureId, std::vector<std::string> & names) const = 0;
+    virtual uint8_t GetRank(uint32_t featureId) const = 0;
+    virtual std::optional<m2::PointD> GetCenter(uint32_t featureId) = 0;
+    virtual bool BelongsToMatchedRegion(m2::PointD const & p) const = 0;
+  };
+
+  LocalityScorer(QueryParams const & params, m2::PointD const & pivot, Delegate & delegate);
+
+  void SetPivotForTesting(m2::PointD const & pivot) { m_pivot = pivot; }
+
+  // Leaves at most |limit| elements of |localities|, ordered by their
+  // features.
+  void GetTopLocalities(MwmSet::MwmId const & countryId, BaseContext const & ctx, CBV const & filter, size_t limit,
+                        std::vector<Locality> & localities);
+
+private:
+  struct ExLocality
+  {
+    ExLocality(Locality && locality, double queryNorm, uint8_t rank);
+
+    uint32_t GetId() const { return m_locality.GetFeatureIndex(); }
+
+    Locality m_locality;
+    double m_queryNorm = 0.0;
+    double m_similarity = 0.0;
+    uint8_t m_rank = 0;
+    double m_distanceToPivot = std::numeric_limits<double>::max();
+    bool m_belongsToMatchedRegion = false;
+  };
+
+  friend std::string DebugPrint(ExLocality const & locality);
+
+  // Leaves at most |limit| elements of |localities|. Candidates are selected with
+  // LeaveTopByExactMatchNormAndRank. Number of candidates typically is much bigger than |limit|
+  // (100 vs 5). Then final localities are selected from candidates with
+  // LeaveTopBySimilarityAndOther.
+  void LeaveTopLocalities(IdfMap & idfs, size_t limit, std::vector<Locality> & localities);
+
+  // Selects at most |limitUniqueIds| best features by exact match, query norm and
+  // rank, and then leaves only localities corresponding to those
+  // features in |els|.
+  void LeaveTopByExactMatchNormAndRank(size_t limitUniqueIds, std::vector<ExLocality> & els) const;
+
+  // Leaves at most |limit| unique best localities by similarity and matched tokens range size. For
+  // elements with the same similarity and matched range size prefers localities from already
+  // matched regions, then the closest one (by distance to pivot), rest of elements are sorted by
+  // rank.
+  void GroupBySimilarityAndOther(std::vector<ExLocality> & els) const;
+
+  void GetDocVecs(uint32_t localityId, std::vector<DocVec> & dvs) const;
+  double GetSimilarity(QueryVec & qv, IdfMap & docIdfs, std::vector<DocVec> & dvs) const;
+
+  QueryParams const & m_params;
+  m2::PointD m_pivot;
+  Delegate & m_delegate;
+};
+}  // namespace search