import logging
import sys


def setup_logger():
    """Set up a logger for the application."""
    logger = logging.getLogger("TravelAssistant")
    logger.setLevel(logging.INFO)

    # avoid duplicate handlers
    if logger.hasHandlers():
        logger.handlers.clear()

    # 创建一个 handler，用于写入日志文件
    # file_handler = logging.FileHandler("app.log")
    # file_handler.setLevel(logging.INFO)

    # 创建一个 handler，用于输出到控制台
    stream_handler = logging.StreamHandler(sys.stdout)
    stream_handler.setLevel(logging.INFO)

    # 定义 handler 的输出格式
    formatter = logging.Formatter(
        '%(asctime)s - %(name)s - %(levelname)s - %(message)s'
    )
    # file_handler.setFormatter(formatter)
    stream_handler.setFormatter(formatter)

    # 给 logger 添加 handler
    # logger.addHandler(file_handler)
    logger.addHandler(stream_handler)

    return logger

# 创建一个实例供其他模块导入
log = setup_logger()