feat: CalorimeterHitsMerger factory simplification

This applies the #666 treatment to the CalorimeterHitsMerger algorithms:

- put all configuration in a single configuration struct for use with
WithPodConfig mixin,
- create a templated factory-factory to use in the plugins,
- replace all old explicit CalorimeterHit factories with the new
factory-factory.

src/algorithms/calorimetry/CalorimeterHitsMerger.cc

@@ -10,35 +10,40 @@
 
 #include "algorithms/calorimetry/CalorimeterHitsMerger.h"
 
-void CalorimeterHitsMerger::initialize() {
+namespace eicrecon {
 
-    if (m_readout.empty()) {
+void CalorimeterHitsMerger::init(const dd4hep::Detector* detector, std::shared_ptr<spdlog::logger>& logger) {
+    m_detector = detector;
+    m_converter = std::make_shared<const dd4hep::rec::CellIDPositionConverter>(const_cast<dd4hep::Detector&>(*detector));
+    m_log = logger;
+
+    if (m_cfg.readout.empty()) {
         m_log->error("readoutClass is not provided, it is needed to know the fields in readout ids");
         return;
     }
 
     try {
-        auto id_desc = m_geoSvc->detector()->readout(m_readout).idSpec();
+        auto id_desc = m_detector->readout(m_cfg.readout).idSpec();
         id_mask = 0;
         std::vector<std::pair<std::string, int>> ref_fields;
-        for (size_t i = 0; i < u_fields.size(); ++i) {
-            id_mask |= id_desc.field(u_fields[i])->mask();
+        for (size_t i = 0; i < m_cfg.fields.size(); ++i) {
+            id_mask |= id_desc.field(m_cfg.fields[i])->mask();
             // use the provided id number to find ref cell, or use 0
-            int ref = i < u_refs.size() ? u_refs[i] : 0;
-            ref_fields.emplace_back(u_fields[i], ref);
+            int ref = i < m_cfg.refs.size() ? m_cfg.refs[i] : 0;
+            ref_fields.emplace_back(m_cfg.fields[i], ref);
         }
         ref_mask = id_desc.encode(ref_fields);
         // debug() << fmt::format("Reference id mask for the fields {:#064b}", ref_mask) << endmsg;
     } catch (...) {
-        auto mess = fmt::format("Failed to load ID decoder for {}", m_readout);
+        auto mess = fmt::format("Failed to load ID decoder for {}", m_cfg.readout);
         m_log->warn(mess);
 //        throw std::runtime_error(mess);
     }
     id_mask = ~id_mask;
-    m_log->info(fmt::format("ID mask in {:s}: {:#064b}", m_readout, id_mask));
+    m_log->info(fmt::format("ID mask in {:s}: {:#064b}", m_cfg.readout, id_mask));
 }
 
-std::unique_ptr<edm4eic::CalorimeterHitCollection> CalorimeterHitsMerger::execute(const edm4eic::CalorimeterHitCollection &input) {
+std::unique_ptr<edm4eic::CalorimeterHitCollection> CalorimeterHitsMerger::process(const edm4eic::CalorimeterHitCollection &input) {
     auto output = std::make_unique<edm4eic::CalorimeterHitCollection>();
 
     // find the hits that belong to the same group (for merging)
@@ -60,14 +65,13 @@ std::unique_ptr<edm4eic::CalorimeterHitCollection> CalorimeterHitsMerger::execut
 
     // reconstruct info for merged hits
     // dd4hep decoders
-    auto poscon = m_geoSvc->cellIDPositionConverter();
-    auto volman = m_geoSvc->detector()->volumeManager();
+    auto volman = m_detector->volumeManager();
 
     for (const auto &[id, ixs] : merge_map) {
         // reference fields id
         const uint64_t ref_id = id | ref_mask;
         // global positions
-        const auto gpos = poscon->position(ref_id);
+        const auto gpos = m_converter->position(ref_id);
         // local positions
         auto alignment = volman.lookupDetElement(ref_id).nominal();
         const auto pos = alignment.worldToLocal(dd4hep::Position(gpos.x(), gpos.y(), gpos.z()));
@@ -115,3 +119,5 @@ std::unique_ptr<edm4eic::CalorimeterHitCollection> CalorimeterHitsMerger::execut
 
     return output;
 }
+
+} // namespace eicrecon

src/algorithms/calorimetry/CalorimeterHitsMerger.h

@@ -16,30 +16,32 @@
 #include <tuple>
 #include <unordered_map>
 
-#include "services/geometry/dd4hep/JDD4hep_service.h"
-#include <Evaluator/DD4hepUnits.h>
+#include <DD4hep/Detector.h>
+#include <DDRec/CellIDPositionConverter.h>
+
 #include <edm4eic/CalorimeterHitCollection.h>
 #include <edm4eic/vector_utils.h>
 #include <spdlog/spdlog.h>
 
+#include "algorithms/interfaces/WithPodConfig.h"
+#include "CalorimeterHitsMergerConfig.h"
+
+namespace eicrecon {
 
-class CalorimeterHitsMerger  {
-public:
+  class CalorimeterHitsMerger : public WithPodConfig<CalorimeterHitsMergerConfig>  {
 
-    std::string m_readout;
-    std::vector<std::string> u_fields;
-    std::vector<int> u_refs;
+  public:
+    void init(const dd4hep::Detector* detector, std::shared_ptr<spdlog::logger>& logger);
+    std::unique_ptr<edm4eic::CalorimeterHitCollection> process(const edm4eic::CalorimeterHitCollection &input);
 
-    std::shared_ptr<JDD4hep_service> m_geoSvc;
+  private:
     uint64_t id_mask{0}, ref_mask{0};
 
+  private:
+    const dd4hep::Detector* m_detector;
+    std::shared_ptr<const dd4hep::rec::CellIDPositionConverter> m_converter;
     std::shared_ptr<spdlog::logger> m_log;
 
-public:
-    CalorimeterHitsMerger() = default;
-    ~CalorimeterHitsMerger() {}
-
-    void initialize();
-    std::unique_ptr<edm4eic::CalorimeterHitCollection> execute(const edm4eic::CalorimeterHitCollection &input);
+  };
 
-}; // class CalorimeterHitsMerger
+} // namespace eicrecon

src/algorithms/calorimetry/CalorimeterHitsMergerConfig.h

@@ -0,0 +1,19 @@
+// Subject to the terms in the LICENSE file found in the top-level directory.
+//
+
+#pragma once
+
+#include <string>
+#include <vector>
+
+namespace eicrecon {
+
+  struct CalorimeterHitsMergerConfig {
+
+    std::string              readout{""};
+    std::vector<std::string> fields{};
+    std::vector<int>         refs{};
+
+  };
+
+} // eicrecon

src/detectors/BEMC/BEMC.cc

@@ -9,12 +9,12 @@
 #include "factories/calorimetry/CalorimeterClusterRecoCoG_factoryT.h"
 #include "factories/calorimetry/CalorimeterHitDigi_factoryT.h"
 #include "factories/calorimetry/CalorimeterHitReco_factoryT.h"
+#include "factories/calorimetry/CalorimeterHitsMerger_factoryT.h"
 
 #include "ProtoCluster_factory_EcalBarrelSciGlassTruthProtoClusters.h"
 #include "ProtoCluster_factory_EcalBarrelSciGlassProtoClusters.h"
 #include "Cluster_factory_EcalBarrelSciGlassMergedTruthClusters.h"
 
-#include "CalorimeterHit_factory_EcalBarrelScFiMergedHits.h"
 #include "ProtoCluster_factory_EcalBarrelScFiProtoClusters.h"
 
 #include "CalorimeterHit_factory_EcalBarrelImagingRecHits.h"
@@ -28,6 +28,7 @@ namespace eicrecon {
   using RawCalorimeterHit_factory_EcalBarrelImagingRawHits = CalorimeterHitDigi_factoryT<>;
   using CalorimeterHit_factory_EcalBarrelSciGlassRecHits = CalorimeterHitReco_factoryT<>;
   using CalorimeterHit_factory_EcalBarrelScFiRecHits = CalorimeterHitReco_factoryT<>;
+  using CalorimeterHit_factory_EcalBarrelScFiMergedHits = CalorimeterHitsMerger_factoryT<>;
   using Cluster_factory_EcalBarrelSciGlassTruthClusters = CalorimeterClusterRecoCoG_factoryT<>;
   using Cluster_factory_EcalBarrelSciGlassClusters = CalorimeterClusterRecoCoG_factoryT<>;
   using Cluster_factory_EcalBarrelScFiClusters = CalorimeterClusterRecoCoG_factoryT<>;

src/detectors/EHCAL/EHCAL.cc

@@ -9,15 +9,16 @@
 #include "factories/calorimetry/CalorimeterClusterRecoCoG_factoryT.h"
 #include "factories/calorimetry/CalorimeterHitDigi_factoryT.h"
 #include "factories/calorimetry/CalorimeterHitReco_factoryT.h"
+#include "factories/calorimetry/CalorimeterHitsMerger_factoryT.h"
 
-#include "CalorimeterHit_factory_HcalEndcapNMergedHits.h"
 #include "ProtoCluster_factory_HcalEndcapNTruthProtoClusters.h"
 #include "ProtoCluster_factory_HcalEndcapNIslandProtoClusters.h"
 
 
 namespace eicrecon {
   using RawCalorimeterHit_factory_HcalEndcapNRawHits = CalorimeterHitDigi_factoryT<>;
   using CalorimeterHit_factory_HcalEndcapNRecHits = CalorimeterHitReco_factoryT<>;
+  using CalorimeterHit_factory_HcalEndcapNMergedHits = CalorimeterHitsMerger_factoryT<>;
   using Cluster_factory_HcalEndcapNTruthClusters = CalorimeterClusterRecoCoG_factoryT<>;
   using Cluster_factory_HcalEndcapNClusters = CalorimeterClusterRecoCoG_factoryT<>;
 }
@@ -57,8 +58,14 @@ extern "C" {
           },
           app   // TODO: Remove me once fixed
         ));
-        app->Add(new JChainFactoryGeneratorT<CalorimeterHit_factory_HcalEndcapNMergedHits>(
-          {"HcalEndcapNRecHits"}, "HcalEndcapNMergedHits"
+        app->Add(new JChainMultifactoryGeneratorT<CalorimeterHit_factory_HcalEndcapNMergedHits>(
+          "HcalEndcapNMergedHits", {"HcalEndcapNRecHits"}, {"HcalEndcapNMergedHits"},
+          {
+            .readout = "HcalEndcapNHits",
+            .fields = {"layer", "slice"},
+            .refs = {1, 0},
+          },
+          app   // TODO: Remove me once fixed
         ));
         app->Add(new JChainFactoryGeneratorT<ProtoCluster_factory_HcalEndcapNTruthProtoClusters>(
           {"HcalEndcapNRecHits", "HcalEndcapNHits"}, "HcalEndcapNTruthProtoClusters"