refactor charge sockets data processing into dedicated class

While here, add method to generate the OSM keys corresponding
to a socket list.

Signed-off-by: Séverin Lemaignan <severin@guakamole.org>

generator/CMakeLists.txt

@@ -251,6 +251,7 @@ target_link_libraries(${PROJECT_NAME}
   storage
   descriptions
   indexer
+  feature_helpers
   cppjansson
   expat::expat
   tess2

generator/osm2meta.cpp

@@ -84,191 +84,6 @@ bool Prefix2Double(std::string const & str, double & d)
 }
 }  // namespace
 
-void MetadataTagProcessorImpl::AggregateChargeSocket(std::string const & k, std::string const & v)
-{
-  auto keys = strings::Tokenize(k, ":");
-  ASSERT(keys[0] == "socket", ());  // key must start with "socket:"
-  if (keys.size() < 2 || keys.size() > 3)
-  {
-    LOG(LWARNING, ("Invalid socket key:", k));
-    return;
-  }
-
-  std::string type(keys[1]);
-
-  bool isOutput = false;
-  if (keys.size() == 3)
-  {
-    if (keys[2] == "output")
-      isOutput = true;
-    else
-      return;  // ignore other suffixes
-  }
-
-  // normalize type if needed
-  // based on recommandations from https://wiki.openstreetmap.org/wiki/Key:socket:*
-  static std::unordered_map<std::string, std::string> const kTypeMap = {
-      {"tesla_supercharger", "nacs"},  // also used in EU for 'type2_combo' -> needs fix in OSM tagging
-      {"tesla_destination", "nacs"},
-      {"tesla_standard", "nacs"},
-      {"tesla", "nacs"},
-      {"tesla_supercharger_ccs", "type2_combo"},
-      {"ccs", "type2_combo"},
-      {"type1_cable", "type1"},
-  };
-
-  auto itMap = kTypeMap.find(type);
-  if (itMap != kTypeMap.end())
-    type = itMap->second;
-
-  // only store sockets type that are relevant to EV charging
-  static std::unordered_set<std::string> const SUPPORTED_TYPES = {
-      "type1", "type1_combo", "type2",  "type2_cable", "type2_combo", "chademo", "nacs",
-      "gb_ac", "gb_dc",       "chaoji", "type3a",      "type3c",      "mcs"};
-
-  if (SUPPORTED_TYPES.find(type) == SUPPORTED_TYPES.end())
-    return;  // unknown type -> ignore
-
-  // find or create descriptor
-  auto it = std::find_if(m_chargeSockets.begin(), m_chargeSockets.end(),
-                         [&](ChargeSocketDescriptor const & d) { return d.type == type; });
-
-  if (it == m_chargeSockets.end())
-  {
-    m_chargeSockets.push_back({type, "y", ""});
-    it = std::prev(m_chargeSockets.end());
-  }
-
-  ASSERT(v.size() > 0, ("empty value for socket key!"));
-
-  if (!isOutput)
-  {
-    if (v == "yes")
-    {
-      it->count = "y";
-    }
-    else
-    {
-      // try to parse count as a number
-      try
-      {
-        auto count = std::stoi(v);
-        if (count <= 0)
-        {
-          LOG(LWARNING, ("Invalid socket count. Removing this socket.", ""));
-          m_chargeSockets.pop_back();
-          return;
-        }
-      }
-      catch (...)
-      {
-        // ignore sockets with invalid counts (ie, can not be parsed to int)
-        // note that if a valid power output is later set for this socket,
-        // the socket will be re-created with a default count of 'y'
-        LOG(LWARNING, ("Invalid count of charging socket. Removing it.", v));
-        m_chargeSockets.pop_back();
-        return;
-      }
-      it->count = v;
-    }
-  }
-  else  // isOutput == true => parse output power
-  {
-    // example value string: "44;22kW;11kva;7400w"
-
-    std::string powerValues = strings::MakeLowerCase(v);
-
-    // replace all occurances of 'VA' by the more standard 'W' unit
-    size_t pos = powerValues.find("va");
-    while (pos != powerValues.npos)
-    {
-      powerValues.replace(pos, 2, "w");
-      pos = powerValues.find("va", pos + 1);
-    }
-
-    // if a given socket type is present several times in the same charging
-    // station with different power outputs, the power outputs would be concatenated
-    // with ';'
-    auto powerTokens = strings::Tokenize(powerValues, ";/");
-
-    // TODO: for now, we only handle the *first* provided
-    // power output.
-    std::string num(powerTokens[0]);
-    strings::Trim(num);
-
-    if (num == "unknown")
-    {
-      it->output_kW = "";
-      return;
-    }
-
-    enum PowerUnit
-    {
-      WATT,
-      KILOWATT,
-      MEGAWATT
-    };
-    PowerUnit unit = KILOWATT;  // if no unit, kW are assumed
-
-    if (num.size() > 2)
-    {
-      // do we have a unit?
-      if (num.back() == 'w')
-      {
-        unit = WATT;
-        num.pop_back();
-        if (num.back() == 'k')
-        {
-          unit = KILOWATT;
-          num.pop_back();
-        }
-        else if (num.back() == 'm')
-        {
-          unit = MEGAWATT;
-          num.pop_back();
-        }
-      }
-    }
-
-    strings::Trim(num);
-    try
-    {
-      double value = std::stod(num);
-      std::ostringstream oss;
-      switch (unit)
-      {
-      case WATT: oss << value / 1000.; break;
-      case MEGAWATT: oss << value * 1000; break;
-      case KILOWATT: oss << value; break;
-      }
-      num = oss.str();
-    }
-    catch (...)
-    {
-      LOG(LWARNING, ("Invalid charging socket power value:", v));
-      num = "";
-    }
-
-    it->output_kW = num;
-  }
-}
-
-std::string MetadataTagProcessorImpl::StringifyChargeSockets() const
-{
-  std::ostringstream oss;
-
-  for (size_t i = 0; i < m_chargeSockets.size(); ++i)
-  {
-    auto const & desc = m_chargeSockets[i];
-
-    oss << desc.type << "|" << desc.count << "|" << desc.output_kW;
-
-    if (i + 1 < m_chargeSockets.size())
-      oss << ";";
-  }
-  return oss.str();
-}
-
 std::string MetadataTagProcessorImpl::ValidateAndFormat_stars(std::string const & v)
 {
   if (v.empty())
@@ -709,9 +524,9 @@ MetadataTagProcessor::~MetadataTagProcessor()
   if (!m_description.IsEmpty())
     m_params.GetMetadata().Set(feature::Metadata::FMD_DESCRIPTION, m_description.GetBuffer());
 
-  if (!m_chargeSockets.empty())
+  if (!m_chargeSockets.GetSockets().empty())
   {
-    auto socketsList = StringifyChargeSockets();
+    auto socketsList = m_chargeSockets.ToString();
     m_params.GetMetadata().Set(feature::Metadata::FMD_CHARGE_SOCKETS, socketsList);
   }
 }
@@ -821,7 +636,7 @@ void MetadataTagProcessor::operator()(std::string const & k, std::string const &
   case Metadata::FMD_SELF_SERVICE: valid = ValidateAndFormat_self_service(v); break;
   case Metadata::FMD_OUTDOOR_SEATING: valid = ValidateAndFormat_outdoor_seating(v); break;
   case Metadata::FMD_NETWORK: valid = ValidateAndFormat_operator(v); break;
-  case Metadata::FMD_CHARGE_SOCKETS: AggregateChargeSocket(k, v); break;
+  case Metadata::FMD_CHARGE_SOCKETS: m_chargeSockets.AggregateChargeSocketKey(k, v); break;
 
   // Metadata types we do not get from OSM.
   case Metadata::FMD_CUISINE:

generator/osm2meta.hpp

@@ -2,6 +2,7 @@
 
 #include "indexer/feature_data.hpp"
 #include "indexer/validate_and_format_contacts.hpp"
+#include "feature_helpers/feature_charge_sockets.hpp"
 
 #include <string>
 
@@ -9,23 +10,6 @@ struct MetadataTagProcessorImpl
 {
   MetadataTagProcessorImpl(FeatureBuilderParams & params) : m_params(params) {}
 
-  /** Parse OSM attributes for socket types and add them to m_chargeSockets.
-   *
-   * Examples of (k,v) pairs:
-   * ("socket:type2_combo", "2")
-   * ("socket:type2_combo:output", "150 kW")
-   * ("socket:chademo", "1")
-   * ("socket:chademo:output", "50") // assumes kW
-   */
-  void AggregateChargeSocket(std::string const & k, std::string const & v);
-
-  /** Output the list of all sockets for a given charging station in the format
-   * <type>|<nb>|[<power>];...
-   *
-   * For instance:
-   * "type2_combo|2|150;chademo|1|50;type2|2|"
-   */
-  std::string StringifyChargeSockets() const;
   std::string ValidateAndFormat_maxspeed(std::string const & v) const;
   static std::string ValidateAndFormat_stars(std::string const & v);
   std::string ValidateAndFormat_operator(std::string const & v) const;
@@ -62,20 +46,9 @@ struct MetadataTagProcessorImpl
   static std::string ValidateAndFormat_outdoor_seating(std::string v);
 
 protected:
-  // struct to store the representation of a charging station socket
-  struct ChargeSocketDescriptor
-  {
-    std::string type;       // https://wiki.openstreetmap.org/wiki/Key:socket:*
-                            // e.g. "type1"
-    std::string count;      // number of sockets or 'y' if OSM tag was set to 'yes'.
-			    // ("" if unknown)
-    std::string output_kW;  // optional power output, in kW ("" if unknown)
-  };
-  typedef std::vector<ChargeSocketDescriptor> ChargeSocketDescriptors;
 
   // stores information about charge sockets in charging stations.
-  // Incrementally completed in AggregateChargeSocket
+  ChargeSocketsHelper m_chargeSockets;
-  ChargeSocketDescriptors m_chargeSockets;
 
   FeatureBuilderParams & m_params;
 };

libs/CMakeLists.txt

@@ -4,6 +4,7 @@ add_subdirectory(descriptions)
 add_subdirectory(drape)
 add_subdirectory(drape_frontend)
 add_subdirectory(editor)
+add_subdirectory(feature_helpers)
 add_subdirectory(ge0)
 add_subdirectory(mwm_diff)
 add_subdirectory(geometry)

libs/feature_helpers/CMakeLists.txt

@@ -0,0 +1,14 @@
+project(feature_helpers)
+
+set(SRC
+  feature_charge_sockets.cpp
+  feature_charge_sockets.hpp
+)
+
+omim_add_library(${PROJECT_NAME} ${SRC})
+target_link_libraries(${PROJECT_NAME}
+  PRIVATE
+    base
+)
+
+# omim_add_test_subdirectory(feature_helpers_tests)

libs/feature_helpers/feature_charge_sockets.cpp

@@ -0,0 +1,392 @@
+
+#include "feature_helpers/feature_charge_sockets.hpp"
+
+#include "base/logging.hpp"
+#include "base/string_utils.hpp"
+
+#include <algorithm>
+#include <iomanip>  // for formatting doubles
+#include <sstream>  // for std::to_string alternative
+#include <string_view>
+#include <vector>
+
+// helper to format doubles (avoids trailing zeros)
+inline std::string to_string_trimmed(double value, int precision = 2)
+{
+  std::ostringstream oss;
+  oss << std::fixed << std::setprecision(precision) << value;
+  auto str = oss.str();
+
+  // Remove trailing zeros
+  auto pos = str.find('.');
+  if (pos != std::string::npos)
+  {
+    // erase trailing zeros
+    while (!str.empty() && str.back() == '0')
+      str.pop_back();
+    // if we end with a '.', remove it too
+    if (!str.empty() && str.back() == '.')
+      str.pop_back();
+  }
+  return str;
+}
+
+// we use a custom tokenizer, as strings::Tokenize discards empty
+// tokens and we want to keep them:
+//
+// Example:
+//    "a||" → ["a", "", ""]
+//    "b|0|" → ["b", "0", ""]
+//    "c||34" → ["c", "", "34"]
+//    "d|43|54" → ["d", "43", "54"]
+std::vector<std::string> tokenize(std::string_view s, char delim = '|')
+{
+  std::vector<std::string> tokens;
+  size_t start = 0;
+  while (true)
+  {
+    size_t pos = s.find(delim, start);
+    if (pos == std::string_view::npos)
+    {
+      tokens.emplace_back(s.substr(start));
+      break;
+    }
+    tokens.emplace_back(s.substr(start, pos - start));
+    start = pos + 1;
+  }
+  return tokens;
+}
+
+ChargeSocketsHelper::ChargeSocketsHelper(std::string const & socketsList) : m_dirty(false)
+{
+  if (socketsList.empty())
+    return;
+
+  auto tokens = tokenize(socketsList, ';');
+
+  for (auto token : tokens)
+  {
+    if (token.empty())
+      continue;
+
+    auto fields = tokenize(token, '|');
+
+    if (fields.size() != 3)
+      continue;  // invalid entry, skip
+
+    ChargeSocketDescriptor desc;
+
+    if (std::find(SUPPORTED_TYPES.begin(), SUPPORTED_TYPES.end(), fields[0]) != SUPPORTED_TYPES.end())
+      desc.type = fields[0];
+    else
+      desc.type = UNKNOWN;
+
+    try
+    {
+      desc.count = std::stoi(std::string(fields[1]));
+    }
+    catch (...)
+    {
+      desc.count = 0;
+    }
+
+    if (fields.size() >= 3)
+    {
+      try
+      {
+        desc.power = std::stod(std::string(fields[2]));
+      }
+      catch (...)
+      {
+        desc.power = 0;
+      }
+    }
+    else
+      desc.power = 0;
+
+    m_chargeSockets.push_back(desc);
+  }
+  m_dirty = true;
+}
+
+void ChargeSocketsHelper::AddSocket(std::string const & type, unsigned int count, double power)
+{
+  if (power < 0)
+  {
+    LOG(LWARNING, ("Invalid socket power. Must be >= 0:", power));
+    return;
+  }
+
+  m_chargeSockets.push_back({type, count, power});
+  m_dirty = true;
+}
+
+void ChargeSocketsHelper::AggregateChargeSocketKey(std::string const & k, std::string const & v)
+{
+  auto keys = strings::Tokenize(k, ":");
+  ASSERT(keys[0] == "socket", ());  // key must start with "socket:"
+  if (keys.size() < 2 || keys.size() > 3)
+  {
+    LOG(LWARNING, ("Invalid socket key:", k));
+    return;
+  }
+
+  std::string type(keys[1]);
+
+  bool isOutput = false;
+  if (keys.size() == 3)
+  {
+    if (keys[2] == "output")
+      isOutput = true;
+    else
+      return;  // ignore other suffixes
+  }
+
+  // normalize type if needed
+  // based on recommandations from https://wiki.openstreetmap.org/wiki/Key:socket:*
+  static std::unordered_map<std::string, std::string> const kTypeMap = {
+      // also sometimes used in EU for 'type2_combo'
+      // -> those cases would require correcting the OSM tagging
+      {"tesla_supercharger", "nacs"},
+      {"tesla_destination", "nacs"},
+      {"tesla_standard", "nacs"},
+      {"tesla", "nacs"},
+      {"tesla_supercharger_ccs", "type2_combo"},
+      {"ccs", "type2_combo"},
+      {"type1_cable", "type1"},
+  };
+
+  auto itMap = kTypeMap.find(type);
+  if (itMap != kTypeMap.end())
+    type = itMap->second;
+
+  if (std::find(SUPPORTED_TYPES.begin(), SUPPORTED_TYPES.end(), type) == SUPPORTED_TYPES.end())
+    type = UNKNOWN;
+
+  // find or create descriptor
+  auto it = std::find_if(m_chargeSockets.begin(), m_chargeSockets.end(),
+                         [&](ChargeSocketDescriptor const & d) { return d.type == type; });
+
+  if (it == m_chargeSockets.end())
+  {
+    m_chargeSockets.push_back({type, 0, 0});
+    it = std::prev(m_chargeSockets.end());
+  }
+
+  ASSERT(v.size() > 0, ("empty value for socket key!"));
+
+  if (!isOutput)
+  {
+    if (v == "yes")
+    {
+      it->count = 0;
+    }
+    else
+    {
+      // try to parse count as a number
+      int count;
+      try
+      {
+        count = std::stoi(v);
+        if (count <= 0)
+        {
+          LOG(LWARNING, ("Invalid socket count. Removing this socket.", ""));
+          // TODO(skadge): incorrect behaviour if invalid count while modifying an existing socket that is not the last
+          // one!
+          m_chargeSockets.pop_back();
+          return;
+        }
+      }
+      catch (...)
+      {
+        // ignore sockets with invalid counts (ie, can not be parsed to int)
+        // note that if a valid power output is later set for this socket,
+        // the socket will be re-created with a default count of 'y'
+        LOG(LWARNING, ("Invalid count of charging socket. Removing it.", v));
+        // TODO(skadge): incorrect behaviour if invalid count while modifying an existing socket that is not the last
+        // one!
+        m_chargeSockets.pop_back();
+        return;
+      }
+      it->count = count;
+    }
+  }
+  else  // isOutput == true => parse output power
+  {
+    // example value string: "44;22kW;11kva;7400w"
+
+    std::string powerValues = strings::MakeLowerCase(v);
+
+    // replace all occurances of 'VA' by the more standard 'W' unit
+    size_t pos = powerValues.find("va");
+    while (pos != powerValues.npos)
+    {
+      powerValues.replace(pos, 2, "w");
+      pos = powerValues.find("va", pos + 1);
+    }
+
+    // if a given socket type is present several times in the same charging
+    // station with different power outputs, the power outputs would be concatenated
+    // with ';'
+    auto powerTokens = strings::Tokenize(powerValues, ";/");
+
+    // TODO: for now, we only handle the *first* provided
+    // power output.
+    std::string num(powerTokens[0]);
+    strings::Trim(num);
+
+    if (num == "unknown")
+    {
+      it->power = 0;
+      m_dirty = true;
+      return;
+    }
+
+    enum PowerUnit
+    {
+      WATT,
+      KILOWATT,
+      MEGAWATT
+    };
+    PowerUnit unit = KILOWATT;  // if no unit, kW are assumed
+
+    if (num.size() > 2)
+    {
+      // do we have a unit?
+      if (num.back() == 'w')
+      {
+        unit = WATT;
+        num.pop_back();
+        if (num.back() == 'k')
+        {
+          unit = KILOWATT;
+          num.pop_back();
+        }
+        else if (num.back() == 'm')
+        {
+          unit = MEGAWATT;
+          num.pop_back();
+        }
+      }
+    }
+
+    strings::Trim(num);
+    double value;
+    try
+    {
+      value = std::stod(num);
+      if (value <= 0)
+      {
+        LOG(LWARNING, ("Invalid charging socket power value:", v));
+        // TODO(skadge): incorrect behaviour if invalid count while modifying an existing socket that is not the last
+        // one!
+        m_chargeSockets.pop_back();
+        return;
+      }
+
+      std::ostringstream oss;
+      switch (unit)
+      {
+      case WATT: value = value / 1000.; break;
+      case MEGAWATT: value = value * 1000; break;
+      case KILOWATT: break;
+      }
+    }
+    catch (...)
+    {
+      LOG(LWARNING, ("Invalid charging socket power value:", v));
+      // TODO(skadge): incorrect behaviour if invalid count while modifying an existing socket that is not the last
+      // one!
+      m_chargeSockets.pop_back();
+      return;
+    }
+
+    it->power = value;
+  }
+
+  m_dirty = true;
+}
+
+ChargeSocketDescriptors ChargeSocketsHelper::GetSockets()
+{
+  if (m_dirty)
+    Sort();
+
+  return m_chargeSockets;
+}
+
+std::string ChargeSocketsHelper::ToString()
+{
+  if (m_dirty)
+    Sort();
+
+  std::ostringstream oss;
+
+  for (size_t i = 0; i < m_chargeSockets.size(); ++i)
+  {
+    auto const & desc = m_chargeSockets[i];
+
+    oss << desc.type << "|";
+    if (desc.count > 0)
+      oss << desc.count;
+    oss << "|";
+    if (desc.power > 0)
+      oss << desc.power;
+
+    if (i + 1 < m_chargeSockets.size())
+      oss << ";";
+  }
+  return oss.str();
+}
+
+OSMKeyValues ChargeSocketsHelper::GetOSMKeyValues()
+{
+  if (m_dirty)
+    Sort();
+
+  std::vector<std::pair<std::string, std::string>> result;
+
+  for (auto const & s : m_chargeSockets)
+  {
+    // Only produce if type is non-empty
+    if (!s.type.empty())
+    {
+      // socket.<type> = count
+      if (s.count > 0)
+      {
+        result.emplace_back("socket:" + s.type, std::to_string(s.count));
+      }
+      else if (s.count == 0)
+      {
+        // special "yes" meaning present, but unknown count
+        result.emplace_back("socket:" + s.type, "yes");
+      }
+
+      // socket.<type>.output = power
+      if (s.power > 0.0)
+        result.emplace_back("socket:" + s.type + ":output", to_string_trimmed(s.power));
+    }
+  }
+
+  return result;
+}
+
+void ChargeSocketsHelper::Sort()
+{
+  size_t const unknownTypeOrder = SUPPORTED_TYPES.size();
+
+  std::sort(m_chargeSockets.begin(), m_chargeSockets.end(),
+            [&](ChargeSocketDescriptor const & a, ChargeSocketDescriptor const & b)
+  {
+    auto const itA = std::find(SUPPORTED_TYPES.begin(), SUPPORTED_TYPES.end(), a.type);
+    auto const orderA = (itA == SUPPORTED_TYPES.end()) ? unknownTypeOrder : std::distance(SUPPORTED_TYPES.begin(), itA);
+    auto const itB = std::find(SUPPORTED_TYPES.begin(), SUPPORTED_TYPES.end(), b.type);
+    auto const orderB = (itB == SUPPORTED_TYPES.end()) ? unknownTypeOrder : std::distance(SUPPORTED_TYPES.begin(), itB);
+
+    if (orderA != orderB)
+      return orderA < orderB;
+    return a.power > b.power;  // Sort by power in descending order for sockets of the same type
+  });
+
+  m_dirty = false;
+}

libs/feature_helpers/feature_charge_sockets.hpp

@@ -0,0 +1,102 @@
+#pragma once
+
+#include <array>
+#include <string>
+#include <utility>  // for std::pair
+#include <vector>
+
+// struct to store the representation of a charging station socket
+struct ChargeSocketDescriptor
+{
+  std::string type;    // https://wiki.openstreetmap.org/wiki/Key:socket:*
+                       // e.g. "type1"
+  unsigned int count;  // number of sockets; 0 means socket present, but unknown count
+                       // (eg, OSM tag for count set to 'yes')
+  double power;        // power output, in kW. 0 means unknown.
+};
+
+typedef std::vector<ChargeSocketDescriptor> ChargeSocketDescriptors;
+
+typedef std::vector<std::pair<std::string, std::string>> OSMKeyValues;
+
+class ChargeSocketsHelper
+{
+public:
+  ChargeSocketsHelper() : m_dirty(false) {}
+
+  /** Create a ChareSocketsHelper instance from an existing list of sockets
+   * stored as "<type>|<nb>|[<power>];..."
+   *
+   * For instance:
+   * "type2_combo|2|150;chademo|1|50;type2|4|"
+   */
+  ChargeSocketsHelper(std::string const & socketsList);
+
+  void AddSocket(std::string const & type, unsigned int count, double power);
+
+  /** Parse OSM attributes for socket types and add them to m_chargeSockets.
+   *
+   * Examples of (k,v) pairs:
+   * ("socket:type2_combo", "2")
+   * ("socket:type2_combo:output", "150 kW")
+   * ("socket:chademo", "1")
+   * ("socket:chademo:output", "50") // assumes kW
+   */
+  void AggregateChargeSocketKey(std::string const & key, std::string const & value);
+
+  /** Returns the current list of sockets, ordered from the most powerful to the least.
+   *
+   * The list is guaranteed to be sorted first by socket type (same ordered as
+   * SUPPORTED_TYPES), then by power (descending).
+   *
+   * Note that this method is not const as it may trigger a re-ordering of the
+   * internal list of sockets.
+   */
+  ChargeSocketDescriptors GetSockets();
+
+  /** Serialize the list of sockets into a string with format "<type>|<nb>|[<power>];..."
+   *
+   * For instance:
+   * "type2_combo|2|150;chademo|1|50;type2|4|"
+   *
+   * The list is guaranteed to be sorted first by socket type (same ordered as
+   * SUPPORTED_TYPES), then by power (descending).
+   *
+   * The same string can be use to re-create a the list of socket by creating a
+   * new instance of ChargeSocketsHelper with the
+   * ChargeSocketsHelper::ChargeSocketsHelper(std::string) ctor.
+   *
+   * Note that this method is not const as it may trigger a re-ordering of the
+   * internal list of sockets.
+   */
+  std::string ToString();
+
+  /** Returns a list of OpenStreetMap (key, value) corresponding to the list of sockets.
+   *
+   * The list is guaranteed to be sorted first by socket type (same ordered as
+   * SUPPORTED_TYPES), then by power (descending).
+   */
+
+  OSMKeyValues GetOSMKeyValues();
+
+  inline static std::string const UNKNOWN = "unknown";
+
+  /** List of supported sockets, ~ordered from high-power to low-power.
+   * This order can be used in the UIs.
+   *
+   * Note that this method is not const as it may trigger a re-ordering of the
+   * internal list of sockets.
+   */
+  static constexpr std::array<std::string_view, 12> SUPPORTED_TYPES = {
+      "mcs",    "type2_combo", "chademo",     "nacs",  "type1", "gb_dc",
+      "chaoji", "type3c",      "type2_cable", "type2", "gb_ac", "type3a"};
+
+protected:
+  ChargeSocketDescriptors m_chargeSockets;
+
+private:
+  /** sort sockets: first by type, then by power (descending).
+   */
+  void Sort();
+  bool m_dirty;
+};

libs/indexer/CMakeLists.txt

@@ -158,6 +158,7 @@ target_link_libraries(${PROJECT_NAME}
   geometry
   protobuf
   coding
+  feature_helpers
 )
 
 omim_add_test_subdirectory(indexer_tests)

libs/indexer/map_object.cpp

@@ -180,74 +180,8 @@ std::string_view MapObject::GetOpeningHours() const
 
 ChargeSocketDescriptors MapObject::GetChargeSockets() const
 {
-  ChargeSocketDescriptors sockets;
-
   auto s = std::string(m_metadata.Get(MetadataID::FMD_CHARGE_SOCKETS));
-  if (s.empty())
+  return ChargeSocketsHelper(s).GetSockets();
-    return sockets;
-
-  // pre-set order of socket types preference (from high-power to low-power).
-  static std::vector<std::string> const kSocketTypeOrder = {"type2_combo", "chademo",     "nacs",
-                                                            "type1",       "type2_cable", "type2"};
-  size_t const unknownTypeOrder = kSocketTypeOrder.size();
-
-  auto tokens = strings::Tokenize(s, ";");
-
-  for (auto token : tokens)
-  {
-    if (token.empty())
-      continue;
-
-    auto fields = strings::Tokenize(token, "|");
-
-    if (fields.size() < 3)
-      continue;  // invalid entry, skip
-
-    ChargeSocketDescriptor desc;
-    desc.type = fields[0];
-
-    try
-    {
-      desc.count = std::stoi(std::string(fields[1]));
-    }
-    catch (...)
-    {
-      desc.count = 0;
-    }
-
-    if (fields.size() >= 3)
-    {
-      try
-      {
-        desc.power = std::stod(std::string(fields[2]));
-      }
-      catch (...)
-      {
-        desc.power = 0;
-      }
-    }
-    else
-      desc.power = 0;
-
-    sockets.push_back(desc);
-  }
-
-  // Sort sockets: first by type, then by power (descending).
-  std::sort(sockets.begin(), sockets.end(), [&](ChargeSocketDescriptor const & a, ChargeSocketDescriptor const & b)
-  {
-    auto const itA = std::find(kSocketTypeOrder.begin(), kSocketTypeOrder.end(), a.type);
-    auto const orderA =
-        (itA == kSocketTypeOrder.end()) ? unknownTypeOrder : std::distance(kSocketTypeOrder.begin(), itA);
-    auto const itB = std::find(kSocketTypeOrder.begin(), kSocketTypeOrder.end(), b.type);
-    auto const orderB =
-        (itB == kSocketTypeOrder.end()) ? unknownTypeOrder : std::distance(kSocketTypeOrder.begin(), itB);
-
-    if (orderA != orderB)
-      return orderA < orderB;
-    return a.power > b.power;  // Sort by power in descending order for sockets of the same type
-  });
-
-  return sockets;
 }
 
 feature::Internet MapObject::GetInternet() const

libs/indexer/map_object.hpp

@@ -10,6 +10,8 @@
 
 #include "coding/string_utf8_multilang.hpp"
 
+#include "feature_helpers/feature_charge_sockets.hpp"
+
 #include <string>
 #include <vector>
 
@@ -17,17 +19,6 @@ namespace osm
 {
 class EditableMapObject;
 
-// struct to store the representation of a charging station socket
-struct ChargeSocketDescriptor
-{
-  std::string type;    // https://wiki.openstreetmap.org/wiki/Key:socket:*
-                       // e.g. "type1"
-  unsigned int count;  // number of sockets; 0 means socket present, but unknown count
-                       // (eg, OSM tag for count set to 'yes')
-  double power;        // power output, in kW. 0 means unknown.
-};
-typedef std::vector<ChargeSocketDescriptor> ChargeSocketDescriptors;
-
 class MapObject
 {
 public: