def __init__(self, path_to_file_to_insert: str, path_to_main_file: str):
self.inserted_file = Stuff.read_the_file(path_to_file_to_insert)
self.main_file = Stuff.read_the_file(path_to_main_file)
if not self._check_the_opportunity_to_enter():
raise Exception("The file you want to write is too large")
self.index_of_start_of_data = \
Stuff.find_index_of_the_start_of_data(self.main_file)
self.bits_per_sample = self._get_bits_per_sample(self.main_file)
self.inserted_name = self._define_filename(path_to_file_to_insert)
self.inserted_hash = Stuff.get_hash(self.inserted_file)
def get_hidden_information(self):
offset = bytes_per_sample = self.bits_per_sample // 8
index = self.index_of_start_of_data + bytes_per_sample
bytes_to_describe_length = 32
index, length_description = self._read_the_flag(
bytes_to_describe_length, index, offset)
length = Stuff.get_int_from_bin(length_description)
length_of_new_bytearray = length // 8
bytes_to_describe_hash = 8
index, length_of_hash_description = self._read_the_flag(
bytes_to_describe_hash, index, offset)
length_of_hash = Stuff.get_int_from_bin(length_of_hash_description)
index, rec_hash = self._read_the_hash(length_of_hash, index, offset)
content_of_recieved = bytearray(length_of_new_bytearray)
index += self._read_the_content(content_of_recieved, length, index,
offset)
actual_hash = Stuff.get_hash(content_of_recieved)
self._compare_the_checksum(actual_hash, rec_hash)
self.create_files(content_of_recieved)
def inscribe(self):
offset = bytes_per_sample = self.bits_per_sample // 8
index = self.index_of_start_of_data + bytes_per_sample
bytes_to_describe_length_of_data = 32
bits_to_write = Stuff.get_bin_str_from_bytearray(self.pickled_files)
list_of_pairs_to_write = list(bits_to_write)
length_description = self._create_description(
list_of_pairs_to_write, bytes_to_describe_length_of_data)
bytes_to_describe_length_of_hash = 8
current_hash = Stuff.get_hash(self.pickled_files)
bits_of_hash = Stuff.get_bin_from_int(current_hash)
hash_pairs = list(bits_of_hash)
hash_description = self._create_description(
hash_pairs, bytes_to_describe_length_of_hash)
index = self.describe_flag_and_get_index(
bytes_to_describe_length_of_data, length_description, index,
offset)
index = self.describe_flag_and_get_index(
bytes_to_describe_length_of_hash, hash_description, index, offset)
index = self.describe_data_and_get_index(hash_pairs, index, offset)
self.describe_data_and_get_index(list_of_pairs_to_write, index, offset)
def get_hidden_information(self):
offset = bytes_per_sample = self.bits_per_sample // 8
index = self.index_of_start_of_data + bytes_per_sample # индекс первого байта
bytes_to_describe_length = 32
index, length_description = self._read_the_flag(
bytes_to_describe_length,
index,
offset
)
length = Stuff.get_int_from_bin(length_description)
length_of_new_bytearray = length // 8
bytes_to_describe_length_of_name = 16
index, length_of_name_description = self._read_the_flag(
bytes_to_describe_length_of_name,
index,
offset
)
length_of_name = Stuff.get_int_from_bin(length_of_name_description)
length_of_name_array = length_of_name // 8
bytes_to_describe_hash = 8
index, length_of_hash_description = self._read_the_flag(
bytes_to_describe_hash,
index,
offset
)
length_of_hash = Stuff.get_int_from_bin(length_of_hash_description) # длина хеша
index, rec_hash = self._read_the_hash(length_of_hash, index, offset)
name_bytearray = bytearray(length_of_name_array)
index = self._read_the_content(name_bytearray, length_of_name, index, offset)
name_of_recieved = name_bytearray.decode()
content_of_recieved = bytearray(length_of_new_bytearray)
self._read_the_content(content_of_recieved, length, index, offset)
actual_hash = Stuff.get_hash(content_of_recieved)
self._compare_the_checksum(actual_hash, rec_hash)
with open('(recieved) ' + name_of_recieved, 'wb') as file:
file.write(content_of_recieved)
def test_get_hash_again(self):
test_array = bytearray(b'0')
result = LSBStuff.get_hash(test_array)
self.assertIsInstance(result, int)
def test_get_hash(self):
test_array = bytearray(bytes('как раз', 'utf-8'))
result = LSBStuff.get_hash(test_array)
self.assertIsInstance(result, int)