From 9a636468e0d6378be117317dedd913e6dbb11727 Mon Sep 17 00:00:00 2001
From: Wojtek Figat <wojtek@figat.pl>
Date: Fri, 13 Oct 2023 15:44:18 +0200
Subject: [PATCH] Fix crash when importing assets in Editor (race-condition
 from Content Importer thread)

#1691 #1679
---
 .../Editor/Modules/ContentDatabaseModule.cs   | 14 ++++++-----
 .../Editor/Modules/ContentImportingModule.cs  |  6 ++---
 .../Progress/Handlers/ImportAssetsProgress.cs | 24 +++++++++----------
 3 files changed, 23 insertions(+), 21 deletions(-)

diff --git a/Source/Editor/Modules/ContentDatabaseModule.cs b/Source/Editor/Modules/ContentDatabaseModule.cs
index 8b7371e44..b1de78456 100644
--- a/Source/Editor/Modules/ContentDatabaseModule.cs
+++ b/Source/Editor/Modules/ContentDatabaseModule.cs
@@ -1135,17 +1135,19 @@ namespace FlaxEditor.Modules
 
             RebuildInternal();
 
-            Editor.ContentImporting.ImportFileEnd += ContentImporting_ImportFileDone;
+            Editor.ContentImporting.ImportFileEnd += (obj, failed) =>
+            {
+                var path = obj.ResultUrl;
+                if (!failed)
+                    FlaxEngine.Scripting.InvokeOnUpdate(() => OnImportFileDone(path));
+            };
             _enableEvents = true;
         }
 
-        private void ContentImporting_ImportFileDone(IFileEntryAction obj, bool failed)
+        private void OnImportFileDone(string path)
         {
-            if (failed)
-                return;
-
             // Check if already has that element
-            var item = Find(obj.ResultUrl);
+            var item = Find(path);
             if (item is BinaryAssetItem binaryAssetItem)
             {
                 // Get asset info from the registry (content layer will update cache it just after import)
diff --git a/Source/Editor/Modules/ContentImportingModule.cs b/Source/Editor/Modules/ContentImportingModule.cs
index c94ba650e..85dd50d35 100644
--- a/Source/Editor/Modules/ContentImportingModule.cs
+++ b/Source/Editor/Modules/ContentImportingModule.cs
@@ -55,7 +55,7 @@ namespace FlaxEditor.Modules
         public event Action ImportingQueueBegin;
 
         /// <summary>
-        /// Occurs when file is being imported.
+        /// Occurs when file is being imported. Can be called on non-main thread.
         /// </summary>
         public event Action<IFileEntryAction> ImportFileBegin;
 
@@ -67,12 +67,12 @@ namespace FlaxEditor.Modules
         public delegate void ImportFileEndDelegate(IFileEntryAction entry, bool failed);
 
         /// <summary>
-        /// Occurs when file importing end.
+        /// Occurs when file importing end. Can be called on non-main thread.
         /// </summary>
         public event ImportFileEndDelegate ImportFileEnd;
 
         /// <summary>
-        /// Occurs when assets importing ends.
+        /// Occurs when assets importing ends. Can be called on non-main thread.
         /// </summary>
         public event Action ImportingQueueEnd;
 
diff --git a/Source/Editor/Progress/Handlers/ImportAssetsProgress.cs b/Source/Editor/Progress/Handlers/ImportAssetsProgress.cs
index 7bbefbc2d..fa1e943f0 100644
--- a/Source/Editor/Progress/Handlers/ImportAssetsProgress.cs
+++ b/Source/Editor/Progress/Handlers/ImportAssetsProgress.cs
@@ -19,25 +19,25 @@ namespace FlaxEditor.Progress.Handlers
         public ImportAssetsProgress()
         {
             var importing = Editor.Instance.ContentImporting;
-            importing.ImportingQueueBegin += OnStart;
-            importing.ImportingQueueEnd += OnEnd;
+            importing.ImportingQueueBegin += () => FlaxEngine.Scripting.InvokeOnUpdate(OnStart);
+            importing.ImportingQueueEnd += () => FlaxEngine.Scripting.InvokeOnUpdate(OnEnd);
             importing.ImportFileBegin += OnImportFileBegin;
         }
 
         private void OnImportFileBegin(IFileEntryAction importFileEntry)
         {
+            string info;
             if (importFileEntry is ImportFileEntry)
-                _currentInfo = string.Format("Importing \'{0}\'", System.IO.Path.GetFileName(importFileEntry.SourceUrl));
+                info = string.Format("Importing \'{0}\'", System.IO.Path.GetFileName(importFileEntry.SourceUrl));
             else
-                _currentInfo = string.Format("Creating \'{0}\'", importFileEntry.SourceUrl);
-            UpdateProgress();
-        }
-
-        private void UpdateProgress()
-        {
-            var importing = Editor.Instance.ContentImporting;
-            var info = string.Format("{0} ({1}/{2})...", _currentInfo, importing.ImportBatchDone, importing.ImportBatchSize);
-            OnUpdate(importing.ImportingProgress, info);
+                info = string.Format("Creating \'{0}\'", importFileEntry.SourceUrl);
+            FlaxEngine.Scripting.InvokeOnUpdate(() =>
+            {
+                _currentInfo = info;
+                var importing = Editor.Instance.ContentImporting;
+                var text = string.Format("{0} ({1}/{2})...", _currentInfo, importing.ImportBatchDone, importing.ImportBatchSize);
+                OnUpdate(importing.ImportingProgress, text);
+            });
         }
     }
 }