✨ wizards: improve performance when many are attached

1 files changed, 24 insertions, 12 deletions

diff --git a/ishtar_common/wizards.py b/ishtar_common/wizards.py
index ddf701ce7..8308deed3 100644
--- a/ishtar_common/wizards.py
+++ b/ishtar_common/wizards.py
@@ -846,10 +846,18 @@ class Wizard(IshtarWizard):
             # material_index management for baseitems
             obj._cached_label_checked = False
             obj.save()
+
+        m2m_dict = {}
+        for k, v in m2m:
+            if k not in m2m_dict:
+                m2m_dict[k] = []
+            if not hasattr(v, "pk"):
+                m2m_dict[k].append(v)
+                continue
+            m2m_dict[k].append(v.pk)
         m2m_items = {}
-        # clear
-        # TODO! perf - to be really optimized
         old_m2ms = {}
+        obj._no_m2m_process = True
         for model in whole_associated_models:
             try:
                 related_model = getattr(obj, model + "s")
@@ -865,16 +873,20 @@ class Wizard(IshtarWizard):
                     ).lower()
                 if hasattr(obj, related_set_name):
                     related_model = getattr(obj, related_set_name)
-            # clear real m2m
-            if hasattr(related_model, "clear"):
-                old_m2ms[model] = []
-                # stock items in order to not recreate them
-                for old_item in related_model.all():
-                    old_m2ms[model].append(old_item)
-                related_model.clear()
-            else:
-                for r in related_model.all():
+            old_m2ms[model] = []
+            for r in related_model.all():
+                old_m2ms[model].append(r)
+                if not hasattr(r, "pk"):
+                    print(f"no pk for {model} - to be managed in wizards")
+                    continue
+                if model in m2m_dict and r.pk in m2m_dict[model]:
+                    # value kept
+                    continue
+                if hasattr(related_model, "remove"):
+                    related_model.remove(r)
+                else:
                     r.delete()
+        obj._no_m2m_process = False
         need_update = False
         for key, value in m2m:
             try:
@@ -943,7 +955,7 @@ class Wizard(IshtarWizard):
                                 val_empty = False
                                 if k.startswith("__empty-"):
                                     val_empty = True
-                                    k = k[len("__empty-") :]
+                                    k = k[len("__empty-"):]
                                 if not hasattr(old_item, k):
                                     continue
                                 old_val = getattr(old_item, k)