LT-73 Export selected studies from study list to local

- Query to get metadata of the selected studies to export
- Download and zip the queried dicom files
- Show and update the progress dialog while querying and exporting studies

Packages/lesiontracker/lib/exportStudies.js

@@ -0,0 +1,97 @@
+/**
+ * Exports requested studies
+ * @param studiesToExport Studies to export
+ */
+exportStudies = function(studiesToExport) {
+    var numberOfFilesToExport = getNumberOfFilesToExport(studiesToExport);
+
+    progressDialog.show("Exporting Studies...", numberOfFilesToExport);
+
+    try {
+        exportStudiesInternal(studiesToExport, numberOfFilesToExport);
+    } catch (err) {
+        progressDialog.close();
+        console.error("Failed to export studies: " + err.message);
+    }
+};
+
+function exportStudiesInternal(studiesToExport, numberOfFilesToExport) {
+    var zip = new JSZip();
+
+    var exportFailed = false;
+    var numberOfFilesExported = 0;
+
+    studiesToExport.forEach(function(study) {
+        sortStudy(study);
+
+        var studyFolder = zip.folder(study.studyInstanceUid);
+
+        study.seriesList.forEach(function(series) {
+            var seriesFolder = studyFolder.folder(series.seriesInstanceUid);
+
+            series.instances.forEach(function(instance) {
+                if (!instance.wadouri) {
+                    return;
+                }
+
+                //  If failed to download a dicom file, skip others
+                if (exportFailed) {
+                    return;
+                }
+
+                //  Download and Zip the dicom file
+                var xhr = new XMLHttpRequest();
+                xhr.open("GET", instance.wadouri, true);
+                xhr.responseType = "arraybuffer";
+
+                //  Downloaded the dicom file completely
+                xhr.onload = function() {
+                    //  If failed to download a dicom file, skip others
+                    if (exportFailed) {
+                        return;
+                    }
+
+                    var responseArrayBuffer = xhr.response;
+                    if (responseArrayBuffer) {
+                        seriesFolder.file(instance.sopInstanceUid + ".dcm", responseArrayBuffer, { binary: true });
+                    }
+
+                    numberOfFilesExported++;
+
+                    if (numberOfFilesExported === numberOfFilesToExport) {
+                        var zipContent = zip.generate({ type: "blob" });
+                        saveAs(zipContent, "studies.zip");
+                    }
+
+                    progressDialog.update(numberOfFilesExported);
+                };
+
+                //  Failed to download the dicom file
+                xhr.onerror = function() {
+                    exportFailed = true;
+
+                    progressDialog.close();
+                    console.error("Failed to export studies!");
+                };
+
+                xhr.send(null);
+            });
+        });
+    });
+}
+
+function getNumberOfFilesToExport(studiesToExport) {
+    var numberOFFilesToExport = 0;
+
+    studiesToExport.forEach(function(study) {
+        study.seriesList.forEach(function(series) {
+            series.instances.forEach(function(instance) {
+                if (instance.wadouri) {
+                    numberOFFilesToExport++;
+                }
+            });
+        });
+    });
+
+    return numberOFFilesToExport;
+}