encryption.py

import os
from cryptography.fernet import Fernet
from dotenv import load_dotenv, set_key

# Path to .env file in the same directory
ENV_PATH = os.path.join(os.path.dirname(os.path.abspath(__file__)), ".env")
load_dotenv(ENV_PATH)

def _get_or_create_encryption_key() -> bytes:
    key = os.environ.get("VAPI_ENCRYPTION_KEY")
    if not key:
        # Generate a new Fernet key
        new_key = Fernet.generate_key().decode()
        # Create .env file if it doesn't exist, and write the key
        with open(ENV_PATH, "a") as f:
            pass  # Ensure file exists
        set_key(ENV_PATH, "VAPI_ENCRYPTION_KEY", new_key)
        # Set in current environment
        os.environ["VAPI_ENCRYPTION_KEY"] = new_key
        key = new_key
    return key.encode()

# Initialize Fernet cipher suite
_fernet = Fernet(_get_or_create_encryption_key())

def encrypt_key(plain_text: str) -> str:
    """Encrypts a plain text string (e.g. API key) to a token string."""
    if not plain_text:
        return ""
    return _fernet.encrypt(plain_text.encode()).decode()

def decrypt_key(encrypted_text: str) -> str:
    """Decrypts a token string back to the original plain text."""
    if not encrypted_text:
        return ""
    return _fernet.decrypt(encrypted_text.encode()).decode()