From 65ed4421e609dda3112f236c13e4db14caa71364 Mon Sep 17 00:00:00 2001
From: AUTOMATIC <16777216c@gmail.com>
Date: Fri, 6 Jan 2023 13:55:50 +0300
Subject: [PATCH] add callback for when the script is unloaded

---
 modules/script_callbacks.py | 18 +++++++++++++++++-
 webui.py                    |  2 ++
 2 files changed, 19 insertions(+), 1 deletion(-)

diff --git a/modules/script_callbacks.py b/modules/script_callbacks.py
index de69fd9f4..608c5300e 100644
--- a/modules/script_callbacks.py
+++ b/modules/script_callbacks.py
@@ -71,6 +71,7 @@ callback_map = dict(
     callbacks_before_component=[],
     callbacks_after_component=[],
     callbacks_image_grid=[],
+    callbacks_script_unloaded=[],
 )
 
 
@@ -171,6 +172,14 @@ def image_grid_callback(params: ImageGridLoopParams):
             report_exception(c, 'image_grid')
 
 
+def script_unloaded_callback():
+    for c in reversed(callback_map['callbacks_script_unloaded']):
+        try:
+            c.callback()
+        except Exception:
+            report_exception(c, 'script_unloaded')
+
+
 def add_callback(callbacks, fun):
     stack = [x for x in inspect.stack() if x.filename != __file__]
     filename = stack[0].filename if len(stack) > 0 else 'unknown file'
@@ -202,7 +211,7 @@ def on_app_started(callback):
 
 def on_model_loaded(callback):
     """register a function to be called when the stable diffusion model is created; the model is
-    passed as an argument"""
+    passed as an argument; this function is also called when the script is reloaded. """
     add_callback(callback_map['callbacks_model_loaded'], callback)
 
 
@@ -279,3 +288,10 @@ def on_image_grid(callback):
        - params: ImageGridLoopParams - parameters to be used for grid creation. Can be modified.
     """
     add_callback(callback_map['callbacks_image_grid'], callback)
+
+
+def on_script_unloaded(callback):
+    """register a function to be called before the script is unloaded. Any hooks/hijacks/monkeying about that
+    the script did should be reverted here"""
+
+    add_callback(callback_map['callbacks_script_unloaded'], callback)
diff --git a/webui.py b/webui.py
index ff6eb6eb5..733a06b51 100644
--- a/webui.py
+++ b/webui.py
@@ -187,12 +187,14 @@ def webui():
 
         sd_samplers.set_samplers()
 
+        modules.script_callbacks.script_unloaded_callback()
         extensions.list_extensions()
 
         localization.list_localizations(cmd_opts.localizations_dir)
 
         modelloader.forbid_loaded_nonbuiltin_upscalers()
         modules.scripts.reload_scripts()
+        modules.script_callbacks.model_loaded_callback(shared.sd_model)
         modelloader.load_upscalers()
 
         for module in [module for name, module in sys.modules.items() if name.startswith("modules.ui")]: