From c1ca4085b61c3963fbe57d1dd9574d73d2c65ac6 Mon Sep 17 00:00:00 2001
From: Ricardo Musch <ricardo@nodeslayers.com>
Date: Tue, 11 Nov 2025 05:22:31 +0000
Subject: [PATCH] Restore the context from deserialized root knob data if this
 exists in the script. This is better than getting the context from the path
 as the path usually doesn't include the Task name/id.

---
 python/tk_nuke/__init__.py | 64 +++++++++++++++++++++++++++++++++++++-
 1 file changed, 63 insertions(+), 1 deletion(-)

diff --git a/python/tk_nuke/__init__.py b/python/tk_nuke/__init__.py
index 0716e35..eadd646 100644
--- a/python/tk_nuke/__init__.py
+++ b/python/tk_nuke/__init__.py
@@ -155,11 +155,53 @@ def __sgtk_on_save_callback():
         # now restart the engine with the new context
         __engine_refresh(new_ctx)
 
+        # Ensure that the sgtk tab and sgtk_context knob exist on the root node.
+        __ensure_sgtk_tab_and_context()
+
+        # save the context into the sgtk_context knob
+        root = nuke.root()
+        if "sgtk_context" in root.knobs():
+            context_knob = root.knob("sgtk_context")
+            context_str = new_ctx.serialize(with_user_credentials=False, use_json=False)
+            context_knob.setValue(context_str)
+            logger.debug("Updated 'sgtk_context' knob with value: %s" % context_str)
+
     except Exception:
         logger.exception("An exception was raised during addOnScriptSave callback.")
         __create_tank_error_menu()
 
 
+def __ensure_sgtk_tab_and_context():
+    """
+    Ensure that the sgtk tab and sgtk_context knob exist on the root node.
+    1. If the "sgtk" tab does not exist, create it.
+    2. If the "sgtk_context" knob does not exist, create it.
+    3. Log actions taken.
+    """
+    logger.debug("Ensuring 'sgtk' tab and 'sgtk_context' knob exist on root node.")
+
+    try:
+        root = nuke.root()
+
+        # Check if the "sgtk" tab exists
+        if "sgtk" not in root.knobs():
+            sgtk_tab = nuke.Tab_Knob("sgtk", "sgtk")
+            root.addKnob(sgtk_tab)
+            logger.debug("Created 'sgtk' tab on root.")
+        else:
+            logger.debug("'sgtk' tab already exists.")
+
+        # Check if the sgtk_context knob exists
+        if "sgtk_context" not in root.knobs():
+            context_knob = nuke.String_Knob("sgtk_context", "ShotGrid Context")
+            root.addKnob(context_knob)
+            logger.debug("Created 'sgtk_context' knob.")
+        else:
+            logger.debug("'sgtk_context' knob already exists.")
+    except Exception as e:
+        logger.exception("Failed to ensure 'sgtk' tab and 'sgtk_context' knob: %s", e)
+
+
 def sgtk_on_load_callback():
     """
     Callback that fires every time a script is loaded.
@@ -217,7 +259,26 @@ def sgtk_on_load_callback():
             if sgtk.platform.current_engine():
                 curr_ctx = sgtk.platform.current_engine().context
 
-            logger.debug("")
+            logger.debug("Trying to get the context from the root.sgtk_context knob if it exists...")
+            # Try to get the context from the root.sgtk_context knob if it exists
+            root = nuke.root()
+            if "sgtk_context" in root.knobs():
+                context_knob = root.knob("sgtk_context")
+                context_str_serialized = context_knob.value()
+                if context_str_serialized:
+                    logger.debug("Found serialized context in knob: %s" % context_str_serialized)
+                    try:
+                        new_ctx = sgtk.Context.deserialize(context_str_serialized)
+                        logger.debug("Deserialized context from knob: %r" % (new_ctx,))
+                        # Now switch to the context appropriate for the file
+                        __engine_refresh(new_ctx)
+                        return
+                    except Exception as e:
+                        logger.debug(
+                            "Could not deserialize context from knob: %s" % (e,)
+                        )
+
+            logger.debug("Computing new context from file path...")
             new_ctx = tk.context_from_path(file_name, curr_ctx)
             logger.debug("Current context: %r" % (curr_ctx,))
             logger.debug("New context: %r" % (new_ctx,))
@@ -274,3 +335,4 @@ def tank_ensure_callbacks_registered(engine=None):
             nuke.removeOnScriptLoad(sgtk_on_load_callback)
             nuke.removeOnScriptSave(__sgtk_on_save_callback)
             g_tank_callbacks_registered = False
+