Fix crash when deleting/renaming asset library while it's visible

Storing the asset library reference by name wasn't a good idea, I thought it
would work with a careful fallback, but it's easier to just use the index
instead. So change to using indices, make sure fallback methods work reliable
and make sure the file list is updated when asset libraries are removed.

I added a new notifier type for the latter, I prefer not using file notifiers
in asset-library/preferences code. We have more than enough values for
notifiers left.

7 files changed, 49 insertions, 31 deletions

diff --git a/source/blender/editors/space_file/filelist.c b/source/blender/editors/space_file/filelist.c
index 5dc5f741ac3..afa1fa0edee 100644
--- a/source/blender/editors/space_file/filelist.c
+++ b/source/blender/editors/space_file/filelist.c
@@ -61,6 +61,7 @@
 #include "BKE_lib_id.h"
 #include "BKE_main.h"
 #include "BKE_main_idmap.h"
+#include "BKE_preferences.h"
 #include "BLO_readfile.h"
 
 #include "DNA_asset_types.h"
@@ -1050,7 +1051,11 @@ static bool filelist_compare_asset_libraries(const FileSelectAssetLibraryUID *li
     return false;
   }
   if (library_a->type == FILE_ASSET_LIBRARY_CUSTOM) {
-    return STREQ(library_a->custom_library_identifier, library_b->custom_library_identifier);
+    /* Don't only check the index, also check that it's valid. */
+    bUserAssetLibrary *library_ptr_a = BKE_preferences_asset_library_find_from_index(
+        &U, library_a->custom_library_index);
+    return (library_ptr_a != NULL) &&
+           (library_a->custom_library_index == library_b->custom_library_index);
   }
 
   return true;
diff --git a/source/blender/editors/space_file/filesel.c b/source/blender/editors/space_file/filesel.c
index 2c66bd39e0a..cd27b7b5773 100644
--- a/source/blender/editors/space_file/filesel.c
+++ b/source/blender/editors/space_file/filesel.c
@@ -119,6 +119,7 @@ static void fileselect_ensure_updated_asset_params(SpaceFile *sfile)
                                                      "FileAssetSelectParams");
     asset_params->base_params.details_flags = U_default.file_space_data.details_flags;
     asset_params->asset_library.type = FILE_ASSET_LIBRARY_LOCAL;
+    asset_params->asset_library.custom_library_index = -1;
   }
 
   FileSelectParams *base_params = &asset_params->base_params;
@@ -419,8 +420,10 @@ static void fileselect_refresh_asset_params(FileAssetSelectParams *asset_params)
 
   /* Ensure valid repo, or fall-back to local one. */
   if (library->type == FILE_ASSET_LIBRARY_CUSTOM) {
-    user_library = BKE_preferences_asset_library_find_from_name(
-        &U, library->custom_library_identifier);
+    BLI_assert(library->custom_library_index >= 0);
+
+    user_library = BKE_preferences_asset_library_find_from_index(&U,
+                                                                 library->custom_library_index);
     if (!user_library) {
       library->type = FILE_ASSET_LIBRARY_LOCAL;
     }
diff --git a/source/blender/editors/space_file/space_file.c b/source/blender/editors/space_file/space_file.c
index 8be02b952a8..09b7e5b348c 100644
--- a/source/blender/editors/space_file/space_file.c
+++ b/source/blender/editors/space_file/space_file.c
@@ -412,6 +412,11 @@ static void file_listener(wmWindow *UNUSED(win),
             ED_area_tag_refresh(area);
           }
           break;
+        case ND_SPACE_ASSET_PARAMS:
+          if (sfile->browse_mode == FILE_BROWSE_MODE_ASSETS) {
+            ED_area_tag_refresh(area);
+          }
+          break;
       }
       break;
     case NC_ASSET: {
diff --git a/source/blender/editors/space_userpref/userpref_ops.c b/source/blender/editors/space_userpref/userpref_ops.c
index 9cc8cc6ddaa..ee23cde78c2 100644
--- a/source/blender/editors/space_userpref/userpref_ops.c
+++ b/source/blender/editors/space_userpref/userpref_ops.c
@@ -170,6 +170,8 @@ static int preferences_asset_library_remove_exec(bContext *UNUSED(C), wmOperator
   if (library) {
     BKE_preferences_asset_library_remove(&U, library);
     U.runtime.is_dirty = true;
+    /* Trigger refresh for the Asset Browser. */
+    WM_main_add_notifier(NC_SPACE | ND_SPACE_ASSET_PARAMS, NULL);
   }
   return OPERATOR_FINISHED;
 }
diff --git a/source/blender/makesdna/DNA_space_types.h b/source/blender/makesdna/DNA_space_types.h
index e07f085d356..4161faca386 100644
--- a/source/blender/makesdna/DNA_space_types.h
+++ b/source/blender/makesdna/DNA_space_types.h
@@ -673,12 +673,13 @@ typedef enum eSpaceSeq_OverlayType {
  */
 typedef struct FileSelectAssetLibraryUID {
   short type;
-  char _pad[6];
+  char _pad[2];
   /**
-   * If showing a custom asset library (#FILE_ASSET_LIBRARY_CUSTOM), this name has to be set to
-   * define which. Can be empty otherwise.
+   * If showing a custom asset library (#FILE_ASSET_LIBRARY_CUSTOM), this is the index of the
+   * #bUserAssetLibrary within #UserDef.asset_libraries.
+   * Should be ignored otherwise (but better set to -1 then, for sanity and debugging).
    */
-  char custom_library_identifier[64]; /* MAX_NAME */
+  int custom_library_index;
 } FileSelectAssetLibraryUID;
 
 /* Config and Input for File Selector */
diff --git a/source/blender/makesrna/intern/rna_space.c b/source/blender/makesrna/intern/rna_space.c
index 59012ce4528..0e779c8cc97 100644
--- a/source/blender/makesrna/intern/rna_space.c
+++ b/source/blender/makesrna/intern/rna_space.c
@@ -2482,11 +2482,10 @@ static int rna_FileAssetSelectParams_asset_library_get(PointerRNA *ptr)
 
   /* Note that the path isn't checked for validity here. If an invalid library path is used, the
    * Asset Browser can give a nice hint on what's wrong. */
-  const bUserAssetLibrary *user_library = BKE_preferences_asset_library_find_from_name(
-      &U, params->asset_library.custom_library_identifier);
-  const int index = BKE_preferences_asset_library_get_index(&U, user_library);
-  if (index > -1) {
-    return FILE_ASSET_LIBRARY_CUSTOM + index;
+  const bUserAssetLibrary *user_library = BKE_preferences_asset_library_find_from_index(
+      &U, params->asset_library.custom_library_index);
+  if (user_library) {
+    return FILE_ASSET_LIBRARY_CUSTOM + params->asset_library.custom_library_index;
   }
 
   BLI_assert(0);
@@ -2500,7 +2499,7 @@ static void rna_FileAssetSelectParams_asset_library_set(PointerRNA *ptr, int val
   /* Simple case: Predefined repo, just set the value. */
   if (value < FILE_ASSET_LIBRARY_CUSTOM) {
     params->asset_library.type = value;
-    params->asset_library.custom_library_identifier[0] = '\0';
+    params->asset_library.custom_library_index = -1;
     BLI_assert(ELEM(value, FILE_ASSET_LIBRARY_LOCAL));
     return;
   }
@@ -2511,10 +2510,12 @@ static void rna_FileAssetSelectParams_asset_library_set(PointerRNA *ptr, int val
   /* Note that the path isn't checked for validity here. If an invalid library path is used, the
    * Asset Browser can give a nice hint on what's wrong. */
   const bool is_valid = (user_library->name[0] && user_library->path[0]);
-  if (user_library && is_valid) {
-    BLI_strncpy(params->asset_library.custom_library_identifier,
-                user_library->name,
-                sizeof(params->asset_library.custom_library_identifier));
+  if (!user_library) {
+    params->asset_library.type = FILE_ASSET_LIBRARY_LOCAL;
+    params->asset_library.custom_library_index = -1;
+  }
+  else if (user_library && is_valid) {
+    params->asset_library.custom_library_index = value - FILE_ASSET_LIBRARY_CUSTOM;
     params->asset_library.type = FILE_ASSET_LIBRARY_CUSTOM;
   }
 }
diff --git a/source/blender/windowmanager/WM_types.h b/source/blender/windowmanager/WM_types.h
index 0ddd0f20c7a..a2cc246e21e 100644
--- a/source/blender/windowmanager/WM_types.h
+++ b/source/blender/windowmanager/WM_types.h
@@ -410,20 +410,21 @@ typedef struct wmNotifier {
 #define ND_SPACE_IMAGE (4 << 16)
 #define ND_SPACE_FILE_PARAMS (5 << 16)
 #define ND_SPACE_FILE_LIST (6 << 16)
-#define ND_SPACE_NODE (7 << 16)
-#define ND_SPACE_OUTLINER (8 << 16)
-#define ND_SPACE_VIEW3D (9 << 16)
-#define ND_SPACE_PROPERTIES (10 << 16)
-#define ND_SPACE_TEXT (11 << 16)
-#define ND_SPACE_TIME (12 << 16)
-#define ND_SPACE_GRAPH (13 << 16)
-#define ND_SPACE_DOPESHEET (14 << 16)
-#define ND_SPACE_NLA (15 << 16)
-#define ND_SPACE_SEQUENCER (16 << 16)
-#define ND_SPACE_NODE_VIEW (17 << 16)
-#define ND_SPACE_CHANGED (18 << 16) /*sent to a new editor type after it's replaced an old one*/
-#define ND_SPACE_CLIP (19 << 16)
-#define ND_SPACE_FILE_PREVIEW (20 << 16)
+#define ND_SPACE_ASSET_PARAMS (7 << 16)
+#define ND_SPACE_NODE (8 << 16)
+#define ND_SPACE_OUTLINER (9 << 16)
+#define ND_SPACE_VIEW3D (10 << 16)
+#define ND_SPACE_PROPERTIES (11 << 16)
+#define ND_SPACE_TEXT (12 << 16)
+#define ND_SPACE_TIME (13 << 16)
+#define ND_SPACE_GRAPH (14 << 16)
+#define ND_SPACE_DOPESHEET (15 << 16)
+#define ND_SPACE_NLA (16 << 16)
+#define ND_SPACE_SEQUENCER (17 << 16)
+#define ND_SPACE_NODE_VIEW (18 << 16)
+#define ND_SPACE_CHANGED (19 << 16) /*sent to a new editor type after it's replaced an old one*/
+#define ND_SPACE_CLIP (20 << 16)
+#define ND_SPACE_FILE_PREVIEW (21 << 16)
 
 /* subtype, 256 entries too */
 #define NOTE_SUBTYPE 0x0000FF00