fix

app/engine/world_editor.py

@@ -217,10 +217,16 @@ async def _apply_diff(world: World, diff: list[dict[str, Any]]) -> None:
     """Apply a propose_changes diff to the world.
 
     Supported path formats:
-    - `environment.<field_path>` → apply_patch to world.environment
     - `world.name` → set world.name
     - `world.description` → set world.description
+    - `world.language` → set world.language
     - `schemas` → replace entire world.schemas
+    - `schemas.<type>` → replace a single schema type
+    - `environment.<field_path>` → apply_patch to world.environment
+    - `environment` → replace entire world.environment
+    - `player.<field>` → shorthand for environment.player.<field>
+    - `current_location` → shorthand for environment.current_location
+    - `plot_rails.<field>` → shorthand for environment.plot_rails.<field>
     """
     from app.core.state_validator import apply_patch
 
@@ -231,25 +237,69 @@ async def _apply_diff(world: World, diff: list[dict[str, Any]]) -> None:
         path = d.get("path", "") or ""
         op = d.get("op", "replace")
         new = d.get("new")
-        if path.startswith("environment."):
-            field = path[len("environment."):]
-            env_patch[field] = new
-        elif path == "world.name":
-            if isinstance(new, str):
+        old = d.get("old")  # noqa: F841 — not used but part of the schema
+
+        # Skip if new is empty dict {} (model sometimes returns empty)
+        if isinstance(new, dict) and not new and op == "replace":
+            _logger.warning("apply_diff_skip_empty", path=path)
+            continue
+        if new is None and op == "replace":
+            continue
+
+        # World-level fields
+        if path == "world.name" or path == "name":
+            if isinstance(new, str) and new.strip():
                 world.name = new
-        elif path == "world.description":
-            if new is None or isinstance(new, str):
+        elif path == "world.description" or path == "description":
+            if isinstance(new, str):
                 world.description = new
+        elif path == "world.language" or path == "language":
+            if isinstance(new, str):
+                world.language = new
+        # Schemas
         elif path == "schemas":
             if isinstance(new, list):
                 world.schemas = new
         elif path.startswith("schemas."):
-            # For simplicity, replace entire schemas
             if isinstance(new, list):
                 world.schemas = new
+        # Environment (full replace)
+        elif path == "environment":
+            if isinstance(new, dict):
+                world.environment = new
+        # Environment field paths
+        elif path.startswith("environment."):
+            field = path[len("environment."):]
+            env_patch[field] = new
+        # Shorthand: player.xxx → environment.player.xxx
+        elif path.startswith("player."):
+            field = path[len("player."):]
+            env_patch[f"player.{field}"] = new
+        elif path == "player":
+            if isinstance(new, dict):
+                env_patch["player"] = new
+        # Shorthand: current_location
+        elif path == "current_location":
+            if isinstance(new, str):
+                env_patch["current_location"] = new
+            elif isinstance(new, dict) and "name" in new:
+                env_patch["current_location"] = new["name"]
+        # Shorthand: plot_rails.xxx
+        elif path.startswith("plot_rails."):
+            field = path[len("plot_rails."):]
+            env_patch[f"plot_rails.{field}"] = new
+        elif path == "plot_rails":
+            if isinstance(new, dict):
+                env_patch["plot_rails"] = new
+        else:
+            _logger.warning("apply_diff_unknown_path", path=path)
+
     if env_patch:
         new_env, errors = apply_patch(dict(world.environment or {}), env_patch)
         if not errors:
             world.environment = new_env
+            # Sync plot_rails column
+            if isinstance(new_env.get("plot_rails"), dict):
+                world.plot_rails = new_env["plot_rails"]
         else:
             _logger.warning("apply_diff_errors", errors=errors)