fix - rancher quota weight reamining weight / free sale

apps/herd/management/commands/merge_duplicate_ranchers.py

@@ -1,6 +1,9 @@
 import logging
 
 from django.core.management.base import BaseCommand
+from django.db.models import Count
+
+from apps.herd.models import Rancher
 
 logger = logging.getLogger("merge_duplicate_ranchers")
 handler = logging.StreamHandler()
@@ -11,6 +14,24 @@ logger.setLevel(logging.INFO)
 
 
 class Command(BaseCommand):
+    help = "Merge ranchers with duplicate national_code and reassign their herds to one main rancher"
 
     def handle(self, *args, **options):
-        pass
+        duplicates = (
+            Rancher.objects.values("national_code")
+            .annotate(count=Count("id"))
+            .filter(count__gt=1)
+        )
+
+        for duplicate in duplicates:
+            ranchers = Rancher.objects.filter(national_code=duplicate["national_code"])
+            main_rancher = ranchers.first()
+            for rancher in ranchers:
+                if rancher != main_rancher:
+                    logger.info(f"Merging rancher {rancher.id} into {main_rancher.id}")
+                    rancher.herd.update(rancher=main_rancher)
+                    rancher.soft_delete()
+                    logger.info(f"Rancher {rancher.id} merged into {main_rancher.id}")
+                    logger.info(f"Rancher {rancher.id} deleted")
+
+        self.stdout.write(self.style.SUCCESS("🎯 Merge process completed successfully."))