# -*- coding: utf-8 -*-

from collections import Callable

from datetime import datetime, timedelta, tzinfo

from requests.compat import basestring

import re

# with thanks to https://code.google.com/p/jquery-localtime/issues/detail?id=4

ISO_8601 = re.compile("^(-?(?:[1-9][0-9]*)?[0-9]{4})-(1[0-2]|0[1-9])-(3[0-1]|0"

"[1-9]|[1-2][0-9])(T(2[0-3]|[0-1][0-9]):([0-5][0-9]):([0"

"-5][0-9])(\.[0-9]+)?(Z|[+-](?:2[0-3]|[0-1][0-9]):[0-5]["

"0-9])?)?$")

def timestamp_parameter(timestamp, allow_none=True):

if timestamp is None:

if allow_none:

return None

raise ValueError("Timestamp value cannot be None")

if isinstance(timestamp, datetime):

return timestamp.isoformat()

if isinstance(timestamp, basestring):

if not ISO_8601.match(timestamp):

raise ValueError(("Invalid timestamp: %s is not a valid ISO-8601"

" formatted date") % timestamp)

return timestamp

raise ValueError("Cannot accept type %s for timestamp" % type(timestamp))

class UTC(tzinfo):

"""Yet another UTC reimplementation, to avoid a dependency on pytz or

dateutil."""

ZERO = timedelta(0)

def __repr__(self):

return 'UTC()'

def dst(self, dt):

return self.ZERO

def tzname(self, dt):

return 'UTC'

def utcoffset(self, dt):

return self.ZERO

def stream_response_to_file(response, path=None):

pre_opened = False

fd = None

if path:

if isinstance(getattr(path, 'write', None), Callable):

pre_opened = True

fd = path

else:

fd = open(path, 'wb')

else:

header = response.headers['content-disposition']

i = header.find('filename=') + len('filename=')

fd = open(header[i:], 'wb')

for chunk in response.iter_content(chunk_size=512):

fd.write(chunk)

if not pre_opened:

fd.close()