[OHIF-235] Lazy processing of DICOM SR for viewport. (#1849)

* Only process SR on consumption of viewport.

* remove debugger

Co-authored-by: Danny Brown <danny.ri.brown@gmail.com>

extensions/dicom-sr/src/getSopClassHandlerModule.js

@@ -55,10 +55,6 @@ function _getDisplaySetsFromSeries(
     throw new Error('No instances were provided');
   }
 
-  const { DisplaySetService, MeasurementService } = servicesManager.services;
-  const dataSources = extensionManager.getDataSources();
-  const dataSource = dataSources[0];
-
   const instance = instances[0];
 
   const {
@@ -68,8 +64,8 @@ function _getDisplaySetsFromSeries(
     SeriesDescription,
     SeriesNumber,
     SeriesDate,
+    ConceptNameCodeSequence,
   } = instance;
-  const { ConceptNameCodeSequence, ContentSequence } = instance;
 
   if (
     !ConceptNameCodeSequence ||
@@ -93,22 +89,36 @@ function _getDisplaySetsFromSeries(
     SeriesInstanceUID,
     StudyInstanceUID,
     SOPClassHandlerId: `${id}.sopClassHandlerModule.${sopClassHandlerName}`,
-    referencedImages: _getReferencedImagesList(ContentSequence),
-    measurements: _getMeasurements(ContentSequence),
+    referencedImages: null,
+    measurements: null,
+    isDerivedDisplaySet: true,
+    isLoaded: false,
     sopClassUids,
+    instance,
   };
 
+  displaySet.load = () => _load(displaySet, servicesManager, extensionManager);
+
+  return [displaySet];
+}
+
+function _load(displaySet, servicesManager, extensionManager) {
+  const { DisplaySetService, MeasurementService } = servicesManager.services;
+  const dataSources = extensionManager.getDataSources();
+  const dataSource = dataSources[0];
+
+  const { ContentSequence } = displaySet.instance;
+
+  displaySet.referencedImages = _getReferencedImagesList(ContentSequence);
+  displaySet.measurements = _getMeasurements(ContentSequence);
+
   const mappings = MeasurementService.getSourceMappings(
     'CornerstoneTools',
     '4'
   );
 
-  if (isRehydratable(displaySet, mappings)) {
-    displaySet.isLocked = false;
-    displaySet.isHydrated = false;
-  } else {
-    displaySet.isLocked = true;
-  }
+  displaySet.isHydrated = false;
+  displaySet.isLocked = isRehydratable(displaySet, mappings) ? false : true;
 
   // Check currently added displaySets and add measurements if the sources exist.
   DisplaySetService.activeDisplaySets.forEach(activeDisplaySet => {
@@ -135,8 +145,6 @@ function _getDisplaySetsFromSeries(
       });
     }
   );
-
-  return [displaySet];
 }
 
 function _checkIfCanAddMeasurementsToDisplaySet(