from pydantic_settings import BaseSettings
from functools import lru_cache
import os
import base64
import json

class Settings(BaseSettings):
    groq_api_key: str
    google_drive_folder_id: str
    google_application_credentials: str = "credentials.json"
    vector_store_path: str = "data/vector_store"
    chunk_size: int = 800
    chunk_overlap: int = 150
    top_k_results: int = 3
    
    class Config:
        env_file = ".env"
    
    def get_google_credentials_dict(self) -> dict:
        """
        Get Google credentials as dictionary.
        Handles both local file and base64 encoded env variable (for HuggingFace Spaces)
        """
        # Check if credentials are provided as base64 in environment variable
        credentials_base64 = os.getenv("GOOGLE_CREDENTIALS_BASE64")
        
        if credentials_base64:
            # Decode base64 credentials (for HuggingFace Spaces)
            try:
                credentials_json = base64.b64decode(credentials_base64).decode('utf-8')
                credentials_dict = json.loads(credentials_json)
                
                # Also write to file for compatibility
                with open("credentials.json", "w") as f:
                    f.write(credentials_json)
                
                print("✅ Google credentials loaded from GOOGLE_CREDENTIALS_BASE64 environment variable")
                return credentials_dict
            except Exception as e:
                raise Exception(f"Error decoding Google credentials from environment variable: {str(e)}")
        
        # Otherwise, read from file (for local development)
        elif os.path.exists(self.google_application_credentials):
            with open(self.google_application_credentials, 'r') as f:
                credentials_dict = json.load(f)
            print("✅ Google credentials loaded from credentials.json file")
            return credentials_dict
        
        else:
            raise Exception(
                "Google credentials not found. Please either:\n"
                "1. Set GOOGLE_CREDENTIALS_BASE64 environment variable (for HuggingFace Spaces), or\n"
                "2. Place credentials.json file in the project root (for local development)"
            )

@lru_cache()
def get_settings():
    return Settings()