fix: return timespan of all partial radiations

fixes #79

src/main/java/org/miracum/streams/ume/obdstofhir/mapper/ObdsProcedureMapper.java

@@ -1,6 +1,7 @@
 package org.miracum.streams.ume.obdstofhir.mapper;
 
 import java.util.*;
+import lombok.val;
 import org.hl7.fhir.r4.model.*;
 import org.miracum.streams.ume.obdstofhir.FhirProperties;
 import org.miracum.streams.ume.obdstofhir.lookup.*;
@@ -500,31 +501,32 @@ public Procedure createRadiotherapyProcedure(
     return stProcedure;
   }
 
+  /**
+   * This will return the whole timespan of completed partial radiations as part of a therapy. If no
+   * usable start or end dates have been found, this method will return a tuple containing `null`
+   * values.
+   *
+   * @param partialRadiations The partial radiations
+   * @return A tuple with start date and end date of all given partial radiations
+   */
   public Tupel<Date, Date> getTimeSpanFromPartialRadiations(List<Bestrahlung> partialRadiations) {
-    // min Beginndatum
-    List<Date> minDates = new ArrayList<>();
-    // maxBeginndatum
-    List<Date> maxDates = new ArrayList<>();
-
-    for (var radio : partialRadiations) {
-      if (radio.getST_Beginn_Datum() != null) {
-        minDates.add(convertObdsDateToDateTimeType(radio.getST_Beginn_Datum()).getValue());
-      }
-      if (radio.getST_Ende_Datum() != null) {
-        maxDates.add(convertObdsDateToDateTimeType(radio.getST_Ende_Datum()).getValue());
-      }
-    }
-
-    Date minDate = null;
-    Date maxDate = null;
-
-    if (!minDates.isEmpty()) {
-      minDate = Collections.min(minDates);
-    }
-    if (!maxDates.isEmpty()) {
-      maxDate = Collections.min(maxDates);
-    }
-
-    return new Tupel<>(minDate, maxDate);
+    val minDates =
+        partialRadiations.stream()
+            .map(radio -> convertObdsDateToDateTimeType(radio.getST_Beginn_Datum()))
+            .filter(Objects::nonNull)
+            .map(PrimitiveType::getValue)
+            .toList();
+
+    val maxDates =
+        partialRadiations.stream()
+            .map(radio -> convertObdsDateToDateTimeType(radio.getST_Ende_Datum()))
+            .filter(Objects::nonNull)
+            .map(PrimitiveType::getValue)
+            .toList();
+
+    return Tupel.<Date, Date>builder()
+        .first(minDates.isEmpty() ? null : Collections.min(minDates))
+        .second(maxDates.isEmpty() ? null : Collections.max(maxDates))
+        .build();
   }
 }

src/test/java/org/miracum/streams/ume/obdstofhir/mapper/ObdsProcedureMapperTest.java

@@ -0,0 +1,48 @@
+package org.miracum.streams.ume.obdstofhir.mapper;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.time.Instant;
+import java.util.Date;
+import java.util.List;
+import lombok.val;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+import org.miracum.streams.ume.obdstofhir.FhirProperties;
+import org.miracum.streams.ume.obdstofhir.model.ADT_GEKID.Menge_Patient.Patient.Menge_Meldung.Meldung.Menge_ST.ST.Menge_Bestrahlung.Bestrahlung;
+import org.miracum.streams.ume.obdstofhir.model.Tupel;
+
+public class ObdsProcedureMapperTest {
+
+  private ObdsProcedureMapper mapper;
+
+  @BeforeEach
+  void setup() {
+    this.mapper = new ObdsProcedureMapper(new FhirProperties());
+  }
+
+  @Test
+  void shouldGetWholeTimeSpanFromPartialRadiations() {
+    val partialRadiations =
+        List.of(
+            getTestPartialRadiationForTimespand("01.01.2024", "31.01.2024"),
+            getTestPartialRadiationForTimespand("01.03.2024", "30.04.2024"),
+            getTestPartialRadiationForTimespand("10.05.2024", "31.05.2024"));
+
+    val actual = this.mapper.getTimeSpanFromPartialRadiations(partialRadiations);
+
+    assertThat(actual)
+        .isEqualTo(
+            Tupel.builder()
+                .first(Date.from(Instant.parse("2024-01-01T00:00:00Z")))
+                .second(Date.from(Instant.parse("2024-05-31T00:00:00Z")))
+                .build());
+  }
+
+  private static Bestrahlung getTestPartialRadiationForTimespand(String start, String end) {
+    Bestrahlung bestrahlung = new Bestrahlung();
+    bestrahlung.setST_Beginn_Datum(start);
+    bestrahlung.setST_Ende_Datum(end);
+    return bestrahlung;
+  }
+}