class Section:
    def __init__(self, f):
        self.f = f
        self.offset = f.readInt64()
        self.size = f.readInt64()
        self.cryptoType = f.readInt64()
        f.readInt64()  # padding
        self.cryptoKey = f.read(16)
        self.cryptoCounter = f.read(16)


class FakeSection:
    def __init__(self, offset, size):
        self.offset = offset
        self.size = size
        self.cryptoType = 1


class Block:
    def __init__(self, f):
        self.f = f
        self.magic = f.read(8)
        self.version = f.readInt8()
        self.type = f.readInt8()
        self.unused = f.readInt8()
        self.blockSizeExponent = f.readInt8()
        self.numberOfBlocks = f.readInt32()
        self.decompressedSize = f.readInt64()
        self.compressedBlockSizeList = [
            f.readInt32() for _ in range(self.numberOfBlocks)
        ]