修复多个问题

backend/app/config.py

@@ -1,3 +1,4 @@
+import json
 import os
 from pathlib import Path
 
@@ -7,16 +8,74 @@ backend_dir = Path(__file__).resolve().parent.parent
 load_dotenv(backend_dir / ".env")
 
 
+def _get_int_env(name: str, default: int) -> int:
+    value = os.getenv(name, "").strip()
+    if not value:
+        return default
+
+    try:
+        return int(value)
+    except ValueError:
+        return default
+
+
+def _get_bool_env(name: str, default: bool = False) -> bool:
+    value = os.getenv(name)
+    if value is None:
+        return default
+
+    return value.strip().lower() in {"1", "true", "yes", "on"}
+
+
+def _get_list_env(name: str, default: list[str]) -> list[str]:
+    value = os.getenv(name, "").strip()
+    if not value:
+        return default
+
+    try:
+        parsed = json.loads(value)
+    except json.JSONDecodeError:
+        parsed = None
+
+    if isinstance(parsed, list):
+        return [str(item).strip() for item in parsed if str(item).strip()]
+
+    return [item.strip() for item in value.split(",") if item.strip()]
+
+
+def _get_path_env(name: str, default: Path) -> Path:
+    value = os.getenv(name, "").strip()
+    if not value:
+        return default.resolve()
+
+    path = Path(value)
+    if not path.is_absolute():
+        path = backend_dir / path
+
+    return path.resolve()
+
+
 class Settings:
-    app_name = "HTML Generator API"
-    api_prefix = "/api"
+    app_name = os.getenv("APP_NAME", "HTML Knowledge API")
+    api_prefix = os.getenv("API_PREFIX", "/api").rstrip("/") or "/api"
     backend_dir = backend_dir
     data_dir = backend_dir / "data"
     database_path = data_dir / "html_generator.db"
     database_url = f"sqlite:///{database_path.as_posix()}"
-    allowed_origins = ["*"]
-    frontend_base_url = os.environ.get("FRONTEND_BASE_URL", "http://localhost:3000")
-    static_dir = backend_dir / "../frontend/public/static"
+    allowed_origins = _get_list_env("ALLOWED_ORIGINS", ["*"])
+    public_base_url = os.getenv("PUBLIC_BASE_URL", "http://localhost:8000").rstrip("/")
+    html_storage_dir = _get_path_env(
+        "HTML_STORAGE_DIR",
+        data_dir / "generated_html",
+    )
+    default_retention_days = max(1, _get_int_env("DEFAULT_RETENTION_DAYS", 7))
+    max_retention_days = max(
+        default_retention_days,
+        _get_int_env("MAX_RETENTION_DAYS", 30),
+    )
+    max_html_length = max(1024, _get_int_env("MAX_HTML_LENGTH", 200_000))
+    api_key = os.getenv("API_KEY", "").strip()
+    allow_unsafe_html = _get_bool_env("ALLOW_UNSAFE_HTML", False)
 
 
-settings = Settings()
+settings = Settings()