assertFalse(filter.accept(smbFile), "Negative size should be rejected");
        verify(smbFile, times(1)).length();

        // zero size -> reject
        reset(smbFile);
        when(smbFile.length()).thenReturn(0L);
        assertFalse(filter.accept(smbFile), "Zero size should be rejected");
        verify(smbFile, times(1)).length();

        // positive size -> accept
        reset(smbFile);

    }

    @Test
    @DisplayName("Should initially have zero data length")
    void testInitialDataLength() {
        // Then
        assertEquals(0, response.getDataLength());
    }

    @Test
    @DisplayName("Should initially have zero data remaining")
    void testInitialDataRemaining() {
        // Then
        assertEquals(0, response.getDataRemaining());

    /**
     * Test constructor AvSingleHost(byte[] raw).
     * Should correctly parse the raw bytes.
     */
    @Test
    void testAvSingleHostRawConstructor() {
        byte[] rawData = new byte[48]; // 8 (size/zero) + 8 (customData) + 32 (machineId)
        // Simulate some data
        rawData[0] = 48; // size
        rawData[16] = 0x01; // machineId start
        rawData[17] = 0x02;

    }

    @Test
    @DisplayName("Test bufDataStart not changed when non-zero")
    void testBufDataStartNotChangedWhenNonZero() throws Exception {
        byte[] buffer = new byte[100];
        int bufferIndex = 0;

        // Set bufDataStart to a non-zero value
        Field bufDataStartField = response.getClass().getSuperclass().getSuperclass().getDeclaredField("bufDataStart");

        byte[] originalDecKey = testDecryptionKey.clone();

        // Ensure keys are not zero initially
        assertFalse(isAllZeros(originalEncKey), "Original encryption key should not be all zeros");
        assertFalse(isAllZeros(originalDecKey), "Original decryption key should not be all zeros");

        // When
        encryptionContext.secureWipeKeys();

        // Test case 3: Zero value
        int zeroValue = 0;
        NdrLong ndrLongZero = new NdrLong(zeroValue);
        assertEquals(zeroValue, ndrLongZero.value, "Constructor should correctly initialize with zero.");

        // Test case 4: Max int value
        int maxIntValue = Integer.MAX_VALUE;

        // Create channels with zero scores (failed state)
        channel1.setState(ChannelState.FAILED);
        channel2.setState(ChannelState.FAILED);

        when(mockChannelManager.getHealthyChannels()).thenReturn(Arrays.asList(channel1, channel2));

        // Should still select a channel even with zero scores
        ChannelInfo selected = loadBalancer.selectChannel(mockMessage);

        }

        @Test
        @DisplayName("Should read file ID correctly with various patterns")
        void testReadFileIdPatterns() throws Exception {
            // Test with all zeros
            byte[] zeroFileId = new byte[16];
            testFileIdReading(zeroFileId);

            // Test with all ones
            byte[] onesFileId = new byte[16];

        }

        @Test
        @DisplayName("Should initialize count to zero")
        void testInitialCountValue() {
            assertEquals(0, response.getCount());
        }

        @Test
        @DisplayName("Should initialize remaining to zero")
        void testInitialRemainingValue() {
            assertEquals(0, response.getRemaining());
        }
    }

        // informationLevel LE at offset 4..5
        assertEquals((byte) 0x04, buf[4]);
        assertEquals((byte) 0x01, buf[5]);
    }

    /**
     * Ensures writeSetupWireFormat writes subcommand and trailing zero, returning 2.
     */
    @Test
    void testWriteSetupWireFormat() {
        // Given
        Trans2FindNext2 next = new Trans2FindNext2(0x1111, 0, "*");
        byte[] dst = new byte[2];

        // When