fix: download cases

progression_backend/steam_api.py

@@ -43,7 +43,9 @@ class SteamWorkshopClient:
         self.session.mount("https://", HTTPAdapter(max_retries=retries))
         self.session.headers.update({"User-Agent": "ProgressionMods/1.0"})
 
-    def get_collections(self, collection_ids: list[str]) -> dict[str, list[str]]:
+    def get_collections(
+        self, collection_ids: list[str]
+    ) -> tuple[dict[str, list[str]], set[str]]:
         payload: dict[str, str | int] = {"collectioncount": len(collection_ids)}
         for index, collection_id in enumerate(collection_ids):
             payload[f"publishedfileids[{index}]"] = collection_id
@@ -55,6 +57,7 @@ class SteamWorkshopClient:
         details = response.json().get("response", {}).get("collectiondetails", [])
 
         result: dict[str, list[str]] = {}
+        collection_references: set[str] = set()
         for detail in details:
             collection_id = str(detail.get("publishedfileid", ""))
             if int(detail.get("result", 0)) != 1:
@@ -63,10 +66,21 @@ class SteamWorkshopClient:
                 detail.get("children", []),
                 key=lambda child: int(child.get("sortorder", 0)),
             )
-            result[collection_id] = [
-                str(child["publishedfileid"]) for child in children
-            ]
-        return result
+            child_ids = [str(child["publishedfileid"]) for child in children]
+            result[collection_id] = child_ids
+            collection_references.update(
+                str(child["publishedfileid"])
+                for child in children
+                if int(child.get("filetype", 0) or 0) == 2
+            )
+
+        # Steam currently reports filetype=2 for nested collections. Also
+        # recognize configured collections by id in case that field is absent.
+        all_children = {
+            workshop_id for workshop_ids in result.values() for workshop_id in workshop_ids
+        }
+        collection_references.update(set(collection_ids) & all_children)
+        return result, collection_references
 
     def get_item_details(self, workshop_ids: list[str]) -> dict[str, WorkshopDetails]:
         result: dict[str, WorkshopDetails] = {}