from __future__ import print_function

import os
import sys
import shutil

assert sys.getwindowsversion() >= (6,0), "Windows Vista or later required"

################################
# first some ctypes symlink implementation since Python doesn't support
# symlinks in windows yet. Borrowed from jaraco.windows project.
from ctypes import windll
from ctypes import c_uint64
from ctypes.wintypes import (
	BOOLEAN, LPWSTR, DWORD, LPVOID, HANDLE, FILETIME,
	WCHAR,
	)
CreateSymbolicLink = windll.kernel32.CreateSymbolicLinkW
CreateSymbolicLink.argtypes = (
	LPWSTR,
	LPWSTR,
	DWORD,
	)
CreateSymbolicLink.restype = BOOLEAN

def handle_nonzero_success(result):
	if result == 0:
		raise RuntimeException(result)

def symlink(link, target, target_is_directory = False):
	"""
	An implementation of os.symlink for Windows (Vista and greater)
	"""
	target_is_directory = target_is_directory or os.path.isdir(target)
	handle_nonzero_success(CreateSymbolicLink(link, target, target_is_directory))

# end ctypes symlink implementation
################################


# create a sample package
package_name = 'sample'
tagged = '{0}-tagged'.format(package_name)
os.mkdir(tagged)
init_file = os.path.join(tagged, '__init__.py')
open(init_file, 'w').close()
assert os.path.exists(init_file)

# now create a symlink to the tagged package so it can be imported
symlink(package_name, tagged)

assert os.path.isdir(package_name)
assert os.path.isfile(os.path.join(package_name, '__init__.py'))

# make sure sample can only be imported from the current directory.
sys.path[:] = ['.']

# and try to import the package
try:
	pkg = __import__(package_name) # fails
	print("Problem does not exist here.")
except ImportError as e:
	print(e)

# now cleanup
os.rmdir(package_name)
shutil.rmtree(tagged)