From f95e99750b6b0a813775a11bea6dc0c20727ee93 Mon Sep 17 00:00:00 2001
From: Robin Hegering <44192264+rheg49@users.noreply.github.com>
Date: Wed, 1 Feb 2023 22:57:01 +0100
Subject: [PATCH] Add shorthand function to merge two pre-existing RTStruct
 structure sets (#70)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

✨ Add class to merge two pre-existing RTStruct structure sets
---
 rt_utils/__init__.py        |  1 +
 rt_utils/rtstruct_merger.py | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 34 insertions(+)
 create mode 100644 rt_utils/rtstruct_merger.py

diff --git a/rt_utils/__init__.py b/rt_utils/__init__.py
index cbf06fe..a17580d 100644
--- a/rt_utils/__init__.py
+++ b/rt_utils/__init__.py
@@ -1,2 +1,3 @@
 from .rtstruct import RTStruct
 from .rtstruct_builder import RTStructBuilder
+from .rtstruct_merger import RTStructMerger
diff --git a/rt_utils/rtstruct_merger.py b/rt_utils/rtstruct_merger.py
new file mode 100644
index 0000000..c1e8a8f
--- /dev/null
+++ b/rt_utils/rtstruct_merger.py
@@ -0,0 +1,33 @@
+from .rtstruct import RTStruct
+from .rtstruct_builder import RTStructBuilder
+from . import ds_helper, image_helper
+
+class RTStructMerger:
+
+
+    @staticmethod
+    def merge_rtstructs(dicom_series_path: str, rt_struct_path1: str, 
+        rt_struct_path2: str) -> RTStruct:
+        """
+        Method to merge two existing RTStruct files belonging to same series data, returning them as one RTStruct
+        """
+
+        rtstruct1 = RTStructBuilder.create_from(dicom_series_path, rt_struct_path1)
+        rtstruct2 = RTStructBuilder.create_from(dicom_series_path, rt_struct_path2)
+        
+        for roi_contour_seq, struct_set_roi_seq, rt_roi_observation_seq in zip(rtstruct1.ds.ROIContourSequence, rtstruct1.ds.StructureSetROISequence, rtstruct1.ds.RTROIObservationsSequence):
+            roi_number = len(rtstruct2.ds.StructureSetROISequence) + 1
+            roi_contour_seq.ReferencedROINumber = roi_number
+            struct_set_roi_seq.ROINumber = roi_number
+            rt_roi_observation_seq.ReferencedROINumber = roi_number
+
+            # check for ROI name duplication
+            for struct_set_roi_seq2 in rtstruct2.ds.StructureSetROISequence:
+                if struct_set_roi_seq.ROIName == struct_set_roi_seq2.ROIName:
+                    struct_set_roi_seq += "_2"
+
+            rtstruct2.ds.ROIContourSequence.append(roi_contour_seq)
+            rtstruct2.ds.StructureSetROISequence.append(struct_set_roi_seq)
+            rtstruct2.ds.RTROIObservationsSequence.append(rt_roi_observation_seq)
+
+        return rtstruct2
\ No newline at end of file