# Copyright 2021 Huawei Technologies Co., Ltd
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# --------------------------------------------------------
# Borrow from Swin Transformer
# Copyright (c) 2021 Microsoft
# Licensed under The MIT License [see LICENSE for details]
# --------------------------------------------------------

import os
import sys
import logging
import functools
from termcolor import colored


@functools.lru_cache()
def create_logger(output_dir, dist_rank=0, name=''):
    # create logger
    logger = logging.getLogger(name)
    logger.setLevel(logging.DEBUG)
    logger.propagate = False

    # create formatter
    fmt = '[%(asctime)s %(name)s] (%(filename)s %(lineno)d): %(levelname)s %(message)s'
    color_fmt = colored('[%(asctime)s %(name)s]', 'green') + \
                colored('(%(filename)s %(lineno)d)', 'yellow') + ': %(levelname)s %(message)s'

    # create console handlers for master process
    if dist_rank == 0:
        console_handler = logging.StreamHandler(sys.stdout)
        console_handler.setLevel(logging.DEBUG)
        console_handler.setFormatter(
            logging.Formatter(fmt=color_fmt, datefmt='%Y-%m-%d %H:%M:%S'))
        logger.addHandler(console_handler)

    # create file handlers
    file_handler = logging.FileHandler(os.path.join(output_dir, f'log_rank{dist_rank}.txt'), mode='a')
    file_handler.setLevel(logging.DEBUG)
    file_handler.setFormatter(logging.Formatter(fmt=fmt, datefmt='%Y-%m-%d %H:%M:%S'))
    logger.addHandler(file_handler)

    return logger