From f6eb060f4fc07042da42b573e24839435bf6f4ef Mon Sep 17 00:00:00 2001
From: x7z4w <x7z4w@noreply.codeberg.org>
Date: Mon, 24 Nov 2025 17:34:56 +0000
Subject: [PATCH] [generator] Implement hash for `OsmElement::Tag`

Signed-off-by: x7z4w <x7z4w@noreply.codeberg.org>
---
 generator/osm_element.cpp            |  2 ++
 generator/osm_element.hpp            | 10 ++++++++++
 generator/road_access_generator.cpp  |  3 ++-
 generator/road_access_generator.hpp  |  5 +++--
 generator/road_penalty_generator.cpp |  4 +++-
 5 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/generator/osm_element.cpp b/generator/osm_element.cpp
index 27872da3c..d9a66f7e5 100644
--- a/generator/osm_element.cpp
+++ b/generator/osm_element.cpp
@@ -7,6 +7,8 @@
 #include "base/stl_helpers.hpp"
 #include "base/string_utils.hpp"
 
+#include "3party/ankerl/unordered_dense.h"
+
 #include <sstream>
 
 std::string DebugPrint(OsmElement::EntityType type)
diff --git a/generator/osm_element.hpp b/generator/osm_element.hpp
index f8d59c6cc..c6f5615b4 100644
--- a/generator/osm_element.hpp
+++ b/generator/osm_element.hpp
@@ -146,3 +146,13 @@ std::string DebugPrintID(OsmElement const & element);
 std::string DebugPrint(OsmElement const & element);
 std::string DebugPrint(OsmElement::EntityType type);
 std::string DebugPrint(OsmElement::Tag const & tag);
+
+template <>
+struct std::hash<OsmElement::Tag>
+{
+    using is_avalanching = void;
+    auto operator()(OsmElement::Tag const & tag) const noexcept -> std::uint64_t {
+        std::string const str = tag.m_key + tag.m_value;
+        return ankerl::unordered_dense::detail::wyhash::hash(str.data(), sizeof(char) * str.size());
+    }
+};
diff --git a/generator/road_access_generator.cpp b/generator/road_access_generator.cpp
index 55a91cc6e..ba8eb466d 100644
--- a/generator/road_access_generator.cpp
+++ b/generator/road_access_generator.cpp
@@ -45,7 +45,8 @@ vector<string> const kBycicleAccessConditionalTags = {"bicycle:conditional"};
 // Some tags assume access:conditional in fact, but doesn't have it.
 // For example if road is tagged as "winter_road = yes",
 // for routing it is like: "access:conditional = no @ (Feb - Dec)"
-std::map<OsmElement::Tag, string> kTagToAccessConditional = {
+// TODO: handle Southern Hemisphere
+std::pair<OsmElement::Tag, string> const kTagToAccessConditional[] = {
     {OsmElement::Tag("winter_road", "yes"), "no @ (Mar - Nov)"},
     {OsmElement::Tag("ice_road", "yes"), "no @ (Mar - Nov)"}};
 
diff --git a/generator/road_access_generator.hpp b/generator/road_access_generator.hpp
index f24c0ef09..11d8b740f 100644
--- a/generator/road_access_generator.hpp
+++ b/generator/road_access_generator.hpp
@@ -9,13 +9,14 @@
 #include "routing/vehicle_mask.hpp"
 
 #include <array>
-#include <map>
 #include <memory>
 #include <optional>
 #include <set>
 #include <string>
 #include <vector>
 
+#include "3party/ankerl/unordered_dense.h"
+
 namespace routing
 {
 class OsmWay2FeaturePoint;
@@ -92,7 +93,7 @@ void Load(Source & src, ConditionalRAVectorT & vec)
 class RoadAccessTagProcessor
 {
 public:
-  using TagMapping = std::map<OsmElement::Tag, RoadAccess::Type>;
+  using TagMapping = ankerl::unordered_dense::map<OsmElement::Tag, RoadAccess::Type>;
   using ConditionalTagsList = std::vector<std::string>;
 
   explicit RoadAccessTagProcessor(VehicleType vehicleType);
diff --git a/generator/road_penalty_generator.cpp b/generator/road_penalty_generator.cpp
index ff3aafab4..bf3828859 100644
--- a/generator/road_penalty_generator.cpp
+++ b/generator/road_penalty_generator.cpp
@@ -21,6 +21,8 @@
 
 #include <optional>
 
+#include "3party/ankerl/unordered_dense.h"
+
 namespace routing_builder
 {
 using namespace feature;
@@ -31,7 +33,7 @@ using std::string, std::vector;
 namespace
 {
 // Unified penalty mapping for all OSM tags that create road penalties
-std::map<OsmElement::Tag, RoadPenalty::Type> const kUnifiedPenaltyMapping = {
+ankerl::unordered_dense::map<OsmElement::Tag, RoadPenalty::Type> const kUnifiedPenaltyMapping = {
     // Traffic calming measures
 
     {OsmElement::Tag("traffic_calming", "rumble_strip"), RoadPenalty::Type::SmallCalming},