# Copyright 2013 The Chromium Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

import logging
import time


class TimeProfile:
    """Class for simple profiling of action, with logging of cost."""

    def __init__(self, description='operation'):
        self._starttime = None
        self._endtime = None
        self._description = description
        self.Start()

    def Start(self):
        self._starttime = time.time()
        self._endtime = None

    def GetDelta(self):
        """Returns the rounded delta.

        Also stops the timer if Stop() has not already been called.
        """
        if self._endtime is None:
            self.Stop(log=False)
        delta = self._endtime - self._starttime
        delta = round(delta, 2) if delta < 10 else round(delta, 1)
        return delta

    def LogResult(self):
        """Logs the result."""
        logging.info(
            '%s seconds to perform %s', self.GetDelta(), self._description
        )

    def Stop(self, log=True):
        """Stop profiling.

        Args:
          log: Log the delta (defaults to true).
        """
        self._endtime = time.time()
        if log:
            self.LogResult()