sdis1819-t7g07

package utils;

import peer.Peer;

import java.io.IOException;

import java.util.Arrays;

public class Chunk {

    private static int SIZE = 64000;

    private byte[] header;

    private byte[] data;

    private byte[] buffer;

    private int chunkDataLength;

    private int chunkLength;

    private String headerMsg;

    public Chunk(byte[] h, FileController fileController) throws IOException{ //Chunk to backup

        this.header = h;

        this.data = getChunkData(fileController);

        this.buffer = mergeByteArrays(this.header, this.data);

                this.chunkLength = this.chunkDataLength + this.header.length;

    }

    public Chunk(byte[] dataBuffer, String messageType, String hashFileId, String chunkNo){ //Chunk to restore

        this.data = dataBuffer;

        this.chunkDataLength = this.data.length;

        String headerMsg = messageType + " " + Utils.version + " " + Peer.getSenderId() + " " + hashFileId + " " + chunkNo + " " + "\r\n\r\n";

        byte[] buf = headerMsg.getBytes();

        this.headerMsg = headerMsg;

        this.header = buf;

        this.buffer = mergeByteArrays(this.header, this.data);

        this.chunkLength = this.header.length + this.chunkDataLength;

    }

    public byte[] getChunkData(FileController fileController) throws IOException{

        byte[] dataBuffer = new byte[SIZE];

        this.chunkDataLength = fileController.getFileStream().read(dataBuffer,0,SIZE);

        return dataBuffer;

    }

    public byte[] getBuffer(){

        this.buffer  = Arrays.copyOf(this.buffer,this.chunkLength);

        return buffer;

    }

    public byte[] mergeByteArrays(byte[] header, byte[] content){

                byte[] ret = new byte[header.length + content.length];

                System.arraycopy(header, 0, ret, 0, header.length);

                System.arraycopy(content, 0, ret, header.length, content.length);

                return ret;

        }

        public String getHeaderMsg(){

        return headerMsg;

    }

}