ParsedUartBusPacket.java

package eu.javaexperience.electronic.uartbus.rpc.client;

import java.util.Arrays;

import eu.javaexperience.electronic.uartbus.PacketReader;
import eu.javaexperience.electronic.uartbus.UartbusTools;

public class ParsedUartBusPacket
{
    public final byte[] rawPacket;
    public final int from;
    public final int to;
    public final byte[] payload;
    
    protected Byte crc8;
    protected Byte validCrc8;
    
    /**
     * payload without the crc8
     * */
    public ParsedUartBusPacket(byte[] data)
    {
        this.rawPacket = data;
        
        int[] read = new int[1];
        int ep = 0;
        this.to = UartbusTools.unpackValue(true, data, ep, read).intValue();
        ep += read[0];
        this.from = UartbusTools.unpackValue(true, data, ep, read).intValue();
        ep += read[0];
        
        payload = Arrays.copyOfRange(data, ep, data.length);
    }
    
    public static ParsedUartBusPacket fromRawPacketWithCrc(byte[] data)
    {
        byte[] raw = Arrays.copyOf(data, data.length-1);
        ParsedUartBusPacket ret = new ParsedUartBusPacket(raw);
        ret.setCrc8(data[data.length-1]);
        
        return ret;
    }
    
    public Byte getCrc8()
    {
        return crc8;
    }
    
    public void setCrc8(Byte b)
    {
        this.crc8 = b;
    }
    
    public PacketReader readPayload()
    {
        return new PacketReader(payload);
    }
    
    public byte getPacketValidCrc8Value()
    {
        if(null == validCrc8)
        {
            validCrc8 = UartbusTools.crc8(rawPacket);
        }
        return validCrc8;
    }
    
    public boolean isValid()
    {
        if(null == crc8)
        {
            return true;
        }
        
        return getPacketValidCrc8Value() == crc8;
    }

    public String toShortUserText()
    {
        StringBuilder sb = new StringBuilder();
        
        sb.append("From: ");
        sb.append(from);
        sb.append(", To: ");
        sb.append(to);
        sb.append(", payload: ");
        sb.append(UartbusTools.formatColonData(payload));
        if(null != crc8)
        {
            sb.append(", crc8: ");
            sb.append(crc8 & 0xff);
            
            if(!isValid())
            {
                sb.append(" != ");
                sb.append(validCrc8 & 0xff);
            }
        }
        return sb.toString();
    }
}