# encoding: utf-8
"""
@author:  sherlock
@contact: sherlockliao01@gmail.com
"""

import errno
import os
import sys
import logging


def mkdir_if_missing(dir_path):
    try:
        os.makedirs(dir_path)
    except OSError as e:
        if e.errno != errno.EEXIST:
            raise


def setup_logger(name, save_dir, distributed_rank):
    logger = logging.getLogger(name)
    logger.setLevel(logging.DEBUG)
    # don't log results for the non-master process
    if distributed_rank > 0:
        return logger
    ch = logging.StreamHandler(stream=sys.stdout)
    ch.setLevel(logging.DEBUG)
    formatter = logging.Formatter("%(asctime)s %(name)s %(levelname)s: %(message)s")
    ch.setFormatter(formatter)
    logger.addHandler(ch)

    if save_dir:
        fh = logging.FileHandler(os.path.join(save_dir, "log.txt"), mode='w')
        fh.setLevel(logging.DEBUG)
        fh.setFormatter(formatter)
        logger.addHandler(fh)

    return logger


class Logger(object):
    def __init__(self, fpath=None):
        self.console = sys.stdout
        self.file = None
        if fpath is not None:
            mkdir_if_missing(os.path.dirname(fpath))
            self.file = open(fpath, 'w')

    def __del__(self):
        self.close()

    def __enter__(self):
        pass

    def __exit__(self, *args):
        self.close()

    def write(self, msg):
        self.console.write(msg)
        if self.file is not None:
            self.file.write(msg)

    def flush(self):
        self.console.flush()
        if self.file is not None:
            self.file.flush()
            os.fsync(self.file.fileno())

    def close(self):
        self.console.close()
        if self.file is not None:
            self.file.close()