SENG302/mock/src/main/java/seng302/Networking/MessageDecoders/XMLMessageDecoder.java

package seng302.Networking.MessageDecoders;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.util.Arrays;

/**
 * Created by hba56 on 20/04/17.
 */
public class XMLMessageDecoder {
    private byte messageVersionNumber;
    private short ackNumber;
    private long timeStamp;
    private byte xmlMsgSubType;
    private short sequenceNumber;
    private short xmlMsgLength;
    private String xmlMessage;

    private byte[] bytes;

    public XMLMessageDecoder(byte[] bytes) {
        this.bytes = bytes;
    }

    public void decode() {
        byte[] ackNumberBytes = Arrays.copyOfRange(bytes, 1, 3);
        byte[] timeStampBytes = Arrays.copyOfRange(bytes, 3, 9);
        byte[] sequenceNumberBytes = Arrays.copyOfRange(bytes, 10, 12);
        byte[] xmlMsgLengthBytes = Arrays.copyOfRange(bytes, 12, 14);
        byte[] xmlMessagebytes = Arrays.copyOfRange(bytes, 14, bytes.length);

        this.xmlMsgSubType = bytes[9];
        this.messageVersionNumber = bytes[0];
        this.ackNumber = bytesToShort(ackNumberBytes);

        this.timeStamp = bytesToLong(timeStampBytes);

        this.sequenceNumber = bytesToShort(sequenceNumberBytes);
        this.xmlMsgLength = bytesToShort(xmlMsgLengthBytes);
        this.xmlMessage = new String(xmlMessagebytes);
    }

    private short bytesToShort(byte[] bytesShort) {
        ByteBuffer byteBuffer = ByteBuffer.allocate(2);
        byteBuffer.order(ByteOrder.LITTLE_ENDIAN);
        byteBuffer.put(bytesShort[0]);
        byteBuffer.put(bytesShort[1]);
        short shortVal = byteBuffer.getShort(0);
        return shortVal;
    }

    private long bytesToLong(byte[] bytesLong) {
        ByteBuffer byteBuffer = ByteBuffer.allocate(8);
        byteBuffer.order(ByteOrder.BIG_ENDIAN);
        byteBuffer.put((byte) 0);
        byteBuffer.put((byte) 0);
        byteBuffer.put(bytesLong[0]);
        byteBuffer.put(bytesLong[1]);
        byteBuffer.put(bytesLong[2]);
        byteBuffer.put(bytesLong[3]);
        byteBuffer.put(bytesLong[4]);
        byteBuffer.put(bytesLong[5]);

//        System.out.println("====decode====");
//        for (byte i:byteBuffer.array()
//                ) {
//            System.out.println(i);
//        }
//        System.out.println("====decode====");

        long longVal = byteBuffer.getLong(0);
        return longVal;
    }

    public byte getMessageVersionNumber() {
        return messageVersionNumber;
    }

    public short getAckNumber() {
        return ackNumber;
    }

    public long getTimeStamp() {
        return timeStamp;
    }

    public byte getXmlMsgSubType() {
        return xmlMsgSubType;
    }

    public short getSequenceNumber() {
        return sequenceNumber;
    }

    public short getXmlMsgLength() {
        return xmlMsgLength;
    }

    public String getXmlMessage() {
        return xmlMessage;
    }
}