#!/usr/bin/env python3
# -*- coding: utf-8 -*-
#
# Copyright (c) 2017 Cisco and/or its affiliates.
#
# 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.
#

import collections

def is_iterable(x):
    return isinstance(x, collections.Iterable) and not isinstance(x, str)

#------------------------------------------------------------------------------
from itertools import tee

# https://docs.python.org/3/library/itertools.html#itertools-recipes
def pairwise(iterable):
    "s -> (s0,s1), (s1,s2), (s2, s3), ..."
    a, b = tee(iterable)
    next(b, None)
    return zip(a, b)


#------------------------------------------------------------------------------
# http://stackoverflow.com/questions/1630320/what-is-the-pythonic-way-to-detect-the-last-element-in-a-python-for-loop
def lookahead(iterable):
    it = iter(iterable)
    last = next(it)
    for val in it:
        yield last, False
        last = val
    yield last, True

#------------------------------------------------------------------------------
# http://stackoverflow.com/questions/10840533/most-pythonic-way-to-delete-a-file-which-may-not-exist

import os, errno

def silentremove(filename):
    try:
        os.remove(filename)
    except OSError as e: # this would be "except OSError, e:" before Python 2.6
        if e.errno != errno.ENOENT: # errno.ENOENT = no such file or directory
            raise # re-raise exception if a different error occured

#------------------------------------------------------------------------------
import socket

def is_local_host(hostname):
    return hostname in ['localhost', '127.0.0.1'] or \
            hostname == socket.gethostname()