config.py

"""
Configuration module for the Library Management System.

Loads settings from environment variables with sensible defaults.
"""

import os
from typing import List


def get_list_from_env(key: str, default: str) -> List[str]:
    """Parse a comma-separated environment variable into a list."""
    value = os.getenv(key, default)
    return [item.strip() for item in value.split(",") if item.strip()]


# Server configuration
HOST: str = os.getenv("HOST", "127.0.0.1")
PORT: int = int(os.getenv("PORT", "8000"))
DEBUG: bool = os.getenv("DEBUG", "false").lower() in ("true", "1", "yes")

# CORS configuration
# In production, set CORS_ORIGINS to your specific domain(s)
# Example: CORS_ORIGINS=https://example.com,https://www.example.com
CORS_ORIGINS: List[str] = get_list_from_env(
    "CORS_ORIGINS",
    "http://localhost:8000,http://127.0.0.1:8000,http://localhost:3000,null"
)
CORS_ALLOW_CREDENTIALS: bool = os.getenv("CORS_ALLOW_CREDENTIALS", "true").lower() in ("true", "1", "yes")
CORS_ALLOW_METHODS: List[str] = get_list_from_env("CORS_ALLOW_METHODS", "GET,POST,PUT,DELETE,OPTIONS")
CORS_ALLOW_HEADERS: List[str] = get_list_from_env("CORS_ALLOW_HEADERS", "Content-Type,Authorization")

# Data configuration
LIBRARY_FILE: str = os.getenv("LIBRARY_FILE", "library.json")

# Logging configuration
LOG_LEVEL: str = os.getenv("LOG_LEVEL", "INFO")
LOG_FILE: str = os.getenv("LOG_FILE", "")  # Empty means stdout only
LOG_FORMAT: str = os.getenv(
    "LOG_FORMAT",
    "%(asctime)s - %(name)s - %(levelname)s - %(message)s"
)

# OpenLibrary API configuration
OPENLIBRARY_BASE_URL: str = os.getenv("OPENLIBRARY_BASE_URL", "https://openlibrary.org")
OPENLIBRARY_TIMEOUT: int = int(os.getenv("OPENLIBRARY_TIMEOUT", "10"))