Barcode scanning and GTIN mapping

backend/app/models.py

@@ -41,7 +41,6 @@ class VariantPack(Base):
 
     id = Column(Integer, primary_key=True, index=True)
     drug_variant_id = Column(Integer, ForeignKey("drug_variants.id"), nullable=False, index=True)
-    label = Column(String, nullable=False)
     pack_unit_name = Column(String, nullable=False, default="pack")
     pack_size_in_base_units = Column(Float, nullable=False, default=1)
     is_active = Column(Boolean, nullable=False, default=True)
@@ -109,6 +108,17 @@ class DispensingAllocation(Base):
     quantity = Column(Float, nullable=False)
 
 
+class GtinMapping(Base):
+    __tablename__ = "gtin_mappings"
+
+    id = Column(Integer, primary_key=True, index=True)
+    gtin = Column(String(14), unique=True, index=True, nullable=False)
+    drug_variant_id = Column(Integer, ForeignKey("drug_variants.id"), nullable=False, index=True)
+    variant_pack_id = Column(Integer, ForeignKey("variant_packs.id"), nullable=False, index=True)
+    created_by_user_id = Column(Integer, ForeignKey("users.id"), nullable=True)
+    created_at = Column(DateTime(timezone=True), server_default=func.now())
+
+
 class AuditLog(Base):
     __tablename__ = "audit_logs"