import logging

LOG_FORMAT = '%(asctime)s %(app_name)s v%(app_version)s [%(levelname)s] %(message)s [%(filename)s:%(lineno)d]'


class ContextFilter(logging.Filter):
    def __init__(self, app_name, app_version):
        self.app_name = app_name.upper()
        self.app_version = app_version
        super().__init__()

    def filter(self, record):
        record.app_name = self.app_name
        record.app_version = self.app_version
        return True


def set_up_logging(app, app_name):
    log = logging.getLogger('werkzeug')
    log.setLevel(logging.WARN)

    logger = app.logger

    for handler in logger.handlers:
        logger.removeHandler(handler)

    log_formatter = logging.Formatter(LOG_FORMAT)

    # set up the new handlers
    stream_handler = logging.StreamHandler()
    stream_handler.setFormatter(log_formatter)
    stream_handler.setLevel(logging.INFO)

    logger.addFilter(ContextFilter(app_name, app.config['VERSION']))
    logger.addHandler(stream_handler)

    app.logger.setLevel(logging.INFO)