import json
import logging
from flask import g
from logging.handlers import TimedRotatingFileHandler


class JSONFormatter(logging.Formatter):
    def format(self, record):
        trace_id = record.msg.get('x-trace-id')
        if trace_id:
            record.msg.pop('x-trace-id')
        else:
            trace_id = g.trace_id

        # Convert the log record to a dictionary
        log_dict = {
            'timestamp': record.created,
            'level': record.levelname,
            'message': json.dumps(record.msg),
            'traceback': None,
            'x-trace-id': trace_id,
        }

        # If the log record has an exception, capture the traceback information
        if record.exc_info:
            tb = self.formatException(record.exc_info)
            log_dict['traceback'] = tb

        # Return the log record as a JSON string
        return json.dumps(log_dict)
    
def log_handler(log_file):
    handler = TimedRotatingFileHandler(
        filename=log_file, 
        interval=1,
        when='D',
    )
    handler.setFormatter(JSONFormatter())
    return handler