class KnotHashV1:
def __init__(self,
lengths,
list_size=256,
initial_position=0,
initial_skip_size=0):
self.position = initial_position
self.skip_size = initial_skip_size
self.list = CircularList(list_size)
for length in lengths:
self.list.reverse(self.position, length)
self.position = self.list.get_actual_position(self.position +
length +
self.skip_size)
self.skip_size += 1
def get_current_position(self):
return self.position
def get_list(self):
return self.list.get_list()
def get_skip_size(self):
return self.skip_size
def compute_checksum(self):
current_list = self.get_list()
return current_list[0] * current_list[1]
def __init__(self, message):
self.message = message
lengths = AsciiConverter.to_ascii_codes(message)
position = 0
skip_size = 0
nums = CircularList(256)
for _ in range(64):
for length in lengths:
nums.reverse(position, length)
position = nums.get_actual_position(position + length +
skip_size)
skip_size += 1
sparse_hash = nums.get_list()
dense_hash = DenseHashProcessor(sparse_hash).get_hash()
self.string_hash = HashFormatter.format(dense_hash)
def testReverse_whenLengthEquals0_shouldNotChangeList(self):
sut = CircularList(5)
sut.reverse(position=0, length=0)
self.assertEqual([0, 1, 2, 3, 4], sut.get_list())
def testReverse_whenLengthEqualsListLengthAndPositionGT0_shouldReverseWithWrap(
self):
sut = CircularList(5)
sut.reverse(1, 5)
self.assertEqual([1, 0, 4, 3, 2], sut.get_list())
def testReverse_whenPositionPlusLengthGTListLength_shouldReverseWithWrap(
self):
sut = CircularList(5)
sut.reverse(4, 2)
self.assertEqual([4, 1, 2, 3, 0], sut.get_list())
def testReverse_whenPositionPlusLengthLTListLength_shouldReverseNoWrap(
self):
sut = CircularList(5)
sut.reverse(1, 3)
self.assertEqual([0, 3, 2, 1, 4], sut.get_list())
def testReverse_whenPositionPlusLengthEqualsListLength_shouldReverseFromPositionToListEnd(
self):
sut = CircularList(5)
sut.reverse(1, 4)
self.assertEqual([0, 4, 3, 2, 1], sut.get_list())