Update src/config.py

src/config.py

@@ -1,25 +1,38 @@
-from pydantic_settings import BaseSettings
+from pydantic_settings import BaseSettings, SettingsConfigDict
+from pydantic import field_validator
 from functools import lru_cache
-import os
+from typing import Literal
+
 
 class Settings(BaseSettings):
-    # API Keys from HF Secrets
-    openai_api_key: str = os.getenv("OPENAI_API_KEY", "")
-    anthropic_api_key: str = os.getenv("ANTHROPIC_API_KEY", "")
-    primo_api_key: str = os.getenv("PRIMO_API_KEY", "")
-    
+    model_config = SettingsConfigDict(
+        case_sensitive=False,
+        env_file=".env",
+        env_file_encoding="utf-8",
+    )
+
+    # API Keys — injected from HF Space secrets as env vars
+    openai_api_key: str = ""
+    anthropic_api_key: str = ""   # optional — only needed for Claude model
+    primo_api_key: str = ""       # optional — search falls back gracefully
+
     # Security
-    admin_password: str = os.getenv("ADMIN_PASSWORD", "")
-    session_secret: str = os.getenv("SESSION_SECRET", "default-secret-change-me")
-    
+    admin_password: str = ""
+    session_secret: str = ""
+
     # App settings
-    environment: str = "production"
+    environment: Literal["development", "production"] = "production"
     maintenance_mode: bool = False
     max_results: int = 5
-    
-    class Config:
-        case_sensitive = False
 
-@lru_cache()
-def get_settings():
+    @field_validator("max_results")
+    @classmethod
+    def reasonable_max_results(cls, v: int) -> int:
+        if not 1 <= v <= 20:
+            raise ValueError("max_results must be between 1 and 20")
+        return v
+
+
+@lru_cache
+def get_settings() -> Settings:
     return Settings()