fix(ui): correctly save videos to gallery on mobile (#2386)

Author: xsahil03x

packages/stream_chat_flutter/CHANGELOG.md

@@ -8,6 +8,8 @@
 🐞 Fixed
 
 - Fixed `.replaceMentions` not escaping special characters in the username.
+- Fixed videos not being saved to gallery correctly on mobile
+  platforms. [[#2357]](https://github.com/GetStream/stream-chat-flutter/issues/2357)
 - Fixed unread indicator button using hardcoded white color instead of theme color
   `colorTheme.barsBg`. [[#2366]](https://github.com/GetStream/stream-chat-flutter/issues/2366)
 - Fixed `GradientAvatars` for users with same-length IDs would have identical

packages/stream_chat_flutter/lib/src/attachment/handler/stream_attachment_handler_io.dart

@@ -198,10 +198,19 @@ class StreamAttachmentHandler extends StreamAttachmentHandlerBase {
 
     // Now that the file is saved, we need to copy it to the user's gallery
     // because the gallery only shows files that are in the gallery folder.
-    await Gal.putImage(path);
+    final copyToGallery = switch (file.mimeType) {
+      final type? when type.startsWith('image/') => Gal.putImage,
+      final type? when type.startsWith('video/') => Gal.putVideo,
+      _ => null,
+    };
 
-    // Once the file is copied to the gallery, we can delete the temporary file.
-    await file.delete();
+    if (copyToGallery != null) {
+      await copyToGallery.call(path);
+
+      // If the file was successfully copied to the gallery, we can safely
+      // delete the temporary file.
+      await file.delete();
+    }
 
     return path;
   }