"""A simple log mechanism styled after PEP 282."""

# This module should be kept compatible with Python 2.1.

# The class here is styled after PEP 282 so that it could later be

# replaced with a standard Python logging implementation.

DEBUG = 1

INFO = 2

WARN = 3

ERROR = 4

FATAL = 5

import sys

class Log:

    def __init__(self, threshold=WARN):

        self.threshold = threshold

    def _log(self, level, msg, args):

        if level >= self.threshold:

            if not args:

                # msg may contain a '%'. If args is empty,

                # don't even try to string-format

                print msg

            else:

                print msg % args

            sys.stdout.flush()

    def log(self, level, msg, *args):

        self._log(level, msg, args)

    def debug(self, msg, *args):

        self._log(DEBUG, msg, args)

    def info(self, msg, *args):

        self._log(INFO, msg, args)

    def warn(self, msg, *args):

        self._log(WARN, msg, args)

    def error(self, msg, *args):

        self._log(ERROR, msg, args)

    def fatal(self, msg, *args):

        self._log(FATAL, msg, args)

_global_log = Log()

log = _global_log.log

debug = _global_log.debug

info = _global_log.info

warn = _global_log.warn

error = _global_log.error

fatal = _global_log.fatal

def set_threshold(level):

    # return the old threshold for use from tests

    old = _global_log.threshold

    _global_log.threshold = level

    return old

def set_verbosity(v):

    if v <= 0:

        set_threshold(WARN)

    elif v == 1:

        set_threshold(INFO)

    elif v >= 2:

        set_threshold(DEBUG)