From 1add3c890d10773b9a41a9e857ce9fa7ea225e49 Mon Sep 17 00:00:00 2001
From: Leonhard Reichenbach <Zehvogel@users.noreply.github.com>
Date: Wed, 19 Apr 2023 09:28:41 +0200
Subject: [PATCH] Add support for EventHeader conversion (#13)

---
 .../k4EDM4hep2LcioConv/k4EDM4hep2LcioConv.h        |  2 ++
 k4EDM4hep2LcioConv/src/k4EDM4hep2LcioConv.cpp      | 14 ++++++++++++++
 2 files changed, 16 insertions(+)

diff --git a/k4EDM4hep2LcioConv/include/k4EDM4hep2LcioConv/k4EDM4hep2LcioConv.h b/k4EDM4hep2LcioConv/include/k4EDM4hep2LcioConv/k4EDM4hep2LcioConv.h
index 487d7ee1..a575e353 100644
--- a/k4EDM4hep2LcioConv/include/k4EDM4hep2LcioConv/k4EDM4hep2LcioConv.h
+++ b/k4EDM4hep2LcioConv/include/k4EDM4hep2LcioConv/k4EDM4hep2LcioConv.h
@@ -140,6 +140,8 @@ lcio::LCCollectionVec* convMCParticles(
   const edm4hep::MCParticleCollection* const mcparticle_coll,
   vec_pair<lcio::MCParticleImpl*, edm4hep::MCParticle>& mc_particles_vec);
 
+void convEventHeader(const edm4hep::EventHeaderCollection* const header_coll, lcio::LCEventImpl* const lcio_event);
+
 void FillMissingCollections(CollectionsPairVectors& collection_pairs);
 
 bool collectionExist(const std::string& collection_name, const lcio::LCEventImpl* lcio_event);
diff --git a/k4EDM4hep2LcioConv/src/k4EDM4hep2LcioConv.cpp b/k4EDM4hep2LcioConv/src/k4EDM4hep2LcioConv.cpp
index 499d20a8..8988441b 100644
--- a/k4EDM4hep2LcioConv/src/k4EDM4hep2LcioConv.cpp
+++ b/k4EDM4hep2LcioConv/src/k4EDM4hep2LcioConv.cpp
@@ -699,6 +699,20 @@ lcio::LCCollectionVec* convMCParticles(
   return mcparticles;
 }
 
+// The EventHeaderCollection should be of length 1
+void convEventHeader(const edm4hep::EventHeaderCollection* const header_coll, lcio::LCEventImpl* const lcio_event)
+{
+  if (header_coll->size() != 1) {
+    return;
+  }
+
+  const auto& header = header_coll->at(0);
+  lcio_event->setEventNumber(header.getEventNumber());
+  lcio_event->setRunNumber(header.getRunNumber());
+  lcio_event->setTimeStamp(header.getTimeStamp());
+  lcio_event->setWeight(header.getWeight());
+}
+
 // Depending on the order of the collections in the parameters,
 // and for the mutual dependencies between some collections,
 // go over the possible missing associated collections and fill them.