public int getTailSpace() {
        return this.buf.length - this.index;
    }

    /**
     * Returns the underlying byte buffer.
     *
     * @return the byte buffer
     */
    public byte[] getBuffer() {
        return this.buf;
    }

    /**
     * Aligns the buffer index to the specified boundary with a fill value.
     *
     * @param boundary the alignment boundary

    @BeforeEach
    void setUp() {
        // Setup buffer cache mocks with lenient stubbing
        lenient().when(mockContext.getBufferCache()).thenReturn(mockBufferCache);
        lenient().when(mockBufferCache.getBuffer()).thenReturn(new byte[8192]);
        handle = new TestDcerpcHandle(mockContext, mockBinding);
    }

    @Nested
    @DisplayName("Binding Parsing Tests")
    class BindingParsingTests {

    void testGetTailSpace() {
        ndrBuffer.setIndex(100);
        assertEquals(buffer.length - 100, ndrBuffer.getTailSpace());
    }

    @Test
    void testGetBuffer() {
        assertSame(buffer, ndrBuffer.getBuffer());
    }

    @Test
    void testAlignWithValue() {
        // Align to 4-byte boundary with a fill value
        ndrBuffer.setIndex(1);
        int alignedBytes = ndrBuffer.align(4, (byte) 0xFF);