++

backend/app/api/presets.py

@@ -1,11 +1,21 @@
 from __future__ import annotations
 
-from fastapi import APIRouter, Request
+from pathlib import Path
+
+from fastapi import APIRouter, HTTPException, Request
+from pydantic import BaseModel, Field
 
 from app.presets import PRESETS
 from app.services.i18n import DEFAULT_LOCALE, locale_from_request
 
-router = APIRouter(prefix="/api")
+router = APIRouter(prefix="/api")
+
+CUSTOM_SIMULATION_DIR = Path(__file__).resolve().parents[3] / "custom_simulation"
+
+
+class CustomPresetPayload(BaseModel):
+    title: str = Field(min_length=1, max_length=160)
+    content: str = Field(min_length=1)
 
 
 def _localize(value, locale: str):
@@ -30,6 +40,62 @@ def _localize(value, locale: str):
 
 
 @router.get("/presets")
-async def get_presets(request: Request):
-    locale = locale_from_request(request)
-    return {"presets": _localize(PRESETS, locale)}
+async def get_presets(request: Request):
+    locale = locale_from_request(request)
+    return {"presets": _localize(PRESETS, locale)}
+
+
+def _custom_presets():
+    CUSTOM_SIMULATION_DIR.mkdir(parents=True, exist_ok=True)
+    presets = []
+    for path in sorted(CUSTOM_SIMULATION_DIR.glob("*.txt"), key=lambda p: p.name.lower()):
+        try:
+            content = path.read_text(encoding="utf-8")
+        except (OSError, UnicodeDecodeError):
+            continue
+        presets.append({
+            "id": f"custom:{path.name}",
+            "name": path.stem,
+            "rules": content,
+            "custom": True,
+            "filename": path.name,
+        })
+    return presets
+
+
+@router.get("/custom-presets")
+async def get_custom_presets():
+    """Load user-authored scenario files from the project custom_simulation folder."""
+    return {"presets": _custom_presets()}
+
+
+@router.post("/custom-presets")
+async def create_custom_preset(payload: CustomPresetPayload):
+    """Save a custom scenario, suffixing duplicate titles with _1, _2, ... ."""
+    title = " ".join(payload.title.strip().split())
+    # Keep unicode letters (including Chinese) while preventing path traversal.
+    title = title.replace("/", "／").replace("\\", "＼")
+    if not title or title in {".", ".."}:
+        raise HTTPException(status_code=400, detail="Title is required")
+
+    CUSTOM_SIMULATION_DIR.mkdir(parents=True, exist_ok=True)
+    candidate = CUSTOM_SIMULATION_DIR / f"{title}.txt"
+    index = 1
+    while candidate.exists():
+        candidate = CUSTOM_SIMULATION_DIR / f"{title}_{index}.txt"
+        index += 1
+
+    try:
+        candidate.write_text(payload.content, encoding="utf-8")
+    except OSError as exc:
+        raise HTTPException(status_code=500, detail=f"Unable to save preset: {exc}") from exc
+
+    return {
+        "preset": {
+            "id": f"custom:{candidate.name}",
+            "name": candidate.stem,
+            "rules": payload.content,
+            "custom": True,
+            "filename": candidate.name,
+        }
+    }