package jmri.jmrix.ipocs.protocol.packets;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertNotNull;

import java.nio.ByteBuffer;
import jmri.util.JUnitUtil;

import org.junit.jupiter.api.*;

public class PacketTest {

    private Packet pkt = null;
    private final byte[] testPacket = { 0x20, 0x03, 0x12 };

  @Test
  public void ackTest() {
    byte[] bytes = new byte[1];
    JUnitUtil.getRandom().nextBytes(bytes);
    pkt.setAck(bytes[0]);
    assertEquals(bytes[0], pkt.getAck());
  }

  @Test
  public void parseTest() {
    // This test is not a really good one - it relies on the actual ServiceLoader.
    // Could be solved by using PowerMockito:
    // stackoverflow.com/questions/21105403/mocking-static-methods-with-mockito
    byte[] successPacket = { ResetControllerPacket.IDENT, 0x03, 0x00 };
    assertNotNull(Packet.parse(ByteBuffer.wrap(successPacket)));
    //assertNull(Packet.parse(ByteBuffer.wrap(testPacket))); // throws IO Exception, packet=null
    //jmri.util.JUnitAppender.suppressErrorMessage("No packet found for identifier 32"); // better to fix method (or test input)
  }

  @Test
  public void serializeTest() {
    pkt.setAck((byte)0x12);
    assertEquals(ByteBuffer.wrap(testPacket), pkt.serialize());
    assertEquals(0x03, pkt.getLength());
  }

    @BeforeEach
    public void setUp() {
        JUnitUtil.setUp();
        pkt = new Packet() {
            @Override
            public byte getId() {
                return (char)0x20;
            }

            @Override
            protected void parseSpecific(ByteBuffer buffer) {
            }

            @Override
            protected byte[] serializeSpecific() {
                return new byte[0];
            }
        };
    }

    @AfterEach
    public void tearDown() {
        pkt = null;
        JUnitUtil.tearDown();
    }

}