fase 5 - Filename Preview API (read-only, op basis van mapping) afgerond

app/api/session.py

@@ -147,3 +147,13 @@ def get_mapping_preview(session_id: str = Query("default", min_length=1)):
         return service.build_mapping_preview(normalized_session_id)
     except ValueError as exc:
         raise HTTPException(status_code=400, detail=str(exc))
+
+
+@router.get("/filename-preview")
+def get_filename_preview(session_id: str = Query("default", min_length=1)):
+    service = SessionService()
+    normalized_session_id = _normalize_session_id(session_id)
+    try:
+        return service.build_filename_preview(normalized_session_id)
+    except ValueError as exc:
+        raise HTTPException(status_code=400, detail=str(exc))

app/services/session_service.py

@@ -347,3 +347,57 @@ class SessionService:
             },
             "mappings": mappings,
         }
+
+    def build_filename_preview(self, session_id: str) -> dict:
+        mapping_preview = self.build_mapping_preview(session_id)
+        previews = []
+
+        for item in mapping_preview["mappings"]:
+            episode = item["episode"]
+            file_payload = item["file"]
+
+            series = (
+                episode.get("series")
+                or episode.get("series_name")
+                or episode.get("show")
+                or "Unknown Series"
+            )
+            year = episode.get("year") or "0000"
+            title = episode.get("title") or "Untitled"
+
+            season_raw = episode.get("season_number") or episode.get("season") or 0
+            episode_raw = episode.get("episode_number") or episode.get("number") or 0
+
+            try:
+                season_number = int(season_raw)
+            except (TypeError, ValueError):
+                season_number = 0
+            try:
+                episode_number = int(episode_raw)
+            except (TypeError, ValueError):
+                episode_number = 0
+
+            source_name = file_payload.get("name") or file_payload.get("path") or ""
+            ext = Path(source_name).suffix
+
+            proposed_filename = (
+                f"{series} ({year}) - S{season_number:02}E{episode_number:02} - {title}{ext}"
+            )
+
+            previews.append(
+                {
+                    "index": item["index"],
+                    "episode_selection_id": item["episode_selection_id"],
+                    "file_selection_id": item["file_selection_id"],
+                    "episode": episode,
+                    "file": file_payload,
+                    "proposed_filename": proposed_filename,
+                }
+            )
+
+        return {
+            "session_id": mapping_preview["session_id"],
+            "counts": mapping_preview["counts"],
+            "template": "{series} ({year}) - S{season:02}E{episode:02} - {title}{ext}",
+            "items": previews,
+        }