"""Provide base classes for the test system"""
from unittest import TestCase
import os
import tempfile

__all__ = ['TestBase', 'FileCreator']


#{ Utilities

class FileCreator(object):
	"""A instance which creates a temporary file with a prefix and a given size
	and provides this info to the user.
	Once it gets deleted, it will remove the temporary file as well."""
	__slots__ = ("_size", "_path")
	
	def __init__(self, size, prefix=''):
		assert size, "Require size to be larger 0"
		
		self._path = tempfile.mktemp(prefix=prefix)
		self._size = size
		
		fp = open(self._path, "wb")
		fp.seek(size-1)
		fp.write('1')
		fp.close()
		
		assert os.path.getsize(self.path) == size

	def __del__(self):
		try:
			os.remove(self.path)
		except OSError:
			pass
		#END exception handling
	

	@property
	def path(self):
		return self._path
		
	@property
	def size(self):
		return self._size

#} END utilities

class TestBase(TestCase):
	"""Foundation used by all tests"""
	
	#{ Configuration
	k_window_test_size = 1000 * 1000 * 8 + 5195
	#} END configuration
	
	#{ Overrides
	@classmethod
	def setUpAll(cls):
		# nothing for now
		pass
		
	#END overrides
	
	#{ Interface
	
	#} END interface