import java.nio.ByteOrder;

import org.junit.jupiter.api.Test;

/**
 * Tests for the PacSignature class.
 */
class PacSignatureTest {

    /**
     * Helper method to write integer in little-endian format.
     */
    private void writeLittleEndianInt(ByteArrayOutputStream baos, int value) {
        ByteBuffer buffer = ByteBuffer.allocate(4);
        buffer.order(ByteOrder.LITTLE_ENDIAN);
        buffer.putInt(value);

/**
 * A {@link PrimitiveSink} that can compute a hash code after reading the input. Each hasher should
 * translate all multibyte values ({@link #putInt(int)}, {@link #putLong(long)}, etc) to bytes in
 * little-endian order.
 *
 * <p><b>Warning:</b> The result of calling any methods after calling {@link #hash} is undefined.
 *
 * <p><b>Warning:</b> Using a specific character encoding when hashing a {@link CharSequence} with

        // Act
        int bytesWritten = write.writeParameterWordsWireFormat(dst, 0);

        // Assert
        assertEquals(10, bytesWritten, "Should write 10 bytes");
        // Check FID (little-endian)
        assertEquals(0x34, dst[0] & 0xFF);
        assertEquals(0x12, dst[1] & 0xFF);
        // Check count
        assertEquals(10, dst[2] & 0xFF);
        assertEquals(0, dst[3] & 0xFF);
        // Check offset

   * @param expectedCount the expected number of roundtrippable permutations
   * @param start the starting bytes encoded as a long as big-endian
   * @param lim the limit of bytes to process encoded as a long as big-endian, or -1 to mean the max
   *     limit for numBytes
   */
  @GwtIncompatible // java.nio.charset.Charset

    checkArgument(
        result == (int) result,
        "the total number of elements (%s) in the arrays must fit in an int",
        result);
    return (int) result;
  }

  /**
   * Returns a big-endian representation of {@code value} in a 4-element byte array; equivalent to
   * {@code ByteBuffer.allocate(4).putInt(value).array()}. For example, the input value {@code

        System.arraycopy(label, 0, suffix, 0, label.length);
        // + 1 byte 0x00
        // + context
        System.arraycopy(context, 0, suffix, label.length + 1, context.length);
        // + 4 byte (== r bits) big endian encoding of L
        suffix[suffix.length - 1] = (byte) 128;

        final DerivationParameters param = new KDFCounterParameters(sessionKey, null /* prefix */, suffix /* suffix */, r /* r */);
        gen.init(param);

        assertTrue(infoString.contains("bytesPerSect=512"), "toString should contain bytesPerSect");
    }

    // Helper methods to write numbers to byte array in little-endian format.
    private void writeInt2(int val, byte[] dst, int dstIndex) {
        dst[dstIndex++] = (byte) val;
        dst[dstIndex++] = (byte) (val >> 8);
    }

        Mac mac = Mac.getInstance("HmacMD5");
        MessageDigest md = MessageDigest.getInstance("MD5");
        mac.init(key);
        byte[] dk = mac.doFinal(MD5_CONSTANT);
        try {
            // little endian
            md.update((byte) (ms_usage & 0xFF));
            md.update((byte) (ms_usage >> 8 & 0xFF));
            md.update((byte) (ms_usage >> 16 & 0xFF));
            md.update((byte) (ms_usage >> 24 & 0xFF));

    checkArgument(
        result == (int) result,
        "the total number of elements (%s) in the arrays must fit in an int",
        result);
    return (int) result;
  }

  /**
   * Returns a big-endian representation of {@code value} in a 2-element byte array; equivalent to
   * {@code ByteBuffer.allocate(2).putChar(value).array()}. For example, the input value {@code
   * '\\u5432'} would yield the byte array {@code {0x54, 0x32}}.

/**
 * Unit tests for {@link HashCode}.
 *
 * @author Dimitris Andreou
 * @author Kurt Alfred Kluever
 */
@NullUnmarked
public class HashCodeTest extends TestCase {
  // note: asInt(), asLong() are in little endian
  private static final ImmutableList<ExpectedHashCode> expectedHashCodes =
      ImmutableList.of(
          new ExpectedHashCode(
              new byte[] {
                (byte) 0xef, (byte) 0xcd, (byte) 0xab, (byte) 0x89,