sdis1819-t4g14

package main.java.protocols;

import main.java.file.FileChunk;

import main.java.file.FileChunkID;

import main.java.file.FileID;

import main.java.listeners.Broker;

import main.java.peer.Peer;

import java.io.*;

import java.util.ArrayList;

import static main.java.utils.Constants.*;

import static main.java.utils.Utilities.*;

public class Restore implements Runnable {

    private File file;

    public Restore(File file) {

        this.file = file;

    }

    @Override

    public void run() {

        byte[] fileData = new byte[0];

        String finalName = file.getName();

        FileID fID = new FileID(sha256(file.getName()), -1);

        String filename = fID.toString();

        Peer.restoring = true;

        System.out.println("\t Restoring file: " + filename + "\n");

        Peer.getMDRListener().chunksReceived.put(filename, new ArrayList<>());

        ArrayList<FileChunk> chunks = new ArrayList<>();

        ArrayList<FileChunk> fileChunks;

        int fileParts = Peer.getDb().getNumChunksOfFile(fID);

        for (int i = 0; i < fileParts; i++) {

            FileChunkID chunkID = new FileChunkID(filename, i);

            //send get chunk

            Broker.sendGETCHUNK(chunkID);

            //receive chunk

            fileChunks = Peer.getMDRListener().chunksReceived.get(filename);

            FileChunk chunkAUX = fileChunks.isEmpty() ? null : Peer.getMDRListener().chunksReceived.get(filename).remove(0);

            while (chunkAUX == null) {

                try {

                    Thread.sleep(500);

                } catch (InterruptedException e) {

                    e.printStackTrace();

                }

                chunkAUX = fileChunks.isEmpty() ? null : Peer.getMDRListener().chunksReceived.get(filename).remove(0);

            }

            chunks.add(chunkAUX);

            //System.out.println("DATABASE : ");

            //Peer.getDb().printDatabase();

        }

        for (int i = 0; i < fileParts; i++) {

            FileChunk chunkTmp = null;

            ArrayList<FileChunk> chunkAUX = null;

            for(FileChunk chunk : chunks) {

                if(chunk.getChunkNo() == i) {

                    chunkTmp = chunk;

                    break;

                }

            }

            if(chunkTmp == null) {

                System.out.println("Missing chunk file!!");

            } else {

                try {

                    fileData = concatBytes(fileData, chunkTmp.getChunkData());

                } catch (IOException e) {

                    e.printStackTrace();

                    }

            }

            File dir = new File("peer"+Peer.getID()+"/restored/");

            if(!dir.exists()) {

                dir.mkdirs();

            }

            FileOutputStream out = null;

            try {

                out = new FileOutputStream("peer"+Peer.getID()+"/restored/" + finalName);

            } catch (FileNotFoundException e) {

                e.printStackTrace();

            }

            try {

                assert out != null;

                out.write(fileData);

            } catch (IOException e) {

                e.printStackTrace();

            }

            try {

                out.close();

            } catch (IOException e) {

                e.printStackTrace();

            }

        }

        Peer.restoring = false;

    }

    private static byte[] concatBytes(byte[] a, byte[] b) throws IOException {

        ByteArrayOutputStream outputStream = new ByteArrayOutputStream( );

        outputStream.write( a );

        outputStream.write( b );

        byte result[] = outputStream.toByteArray( );

        return result;

    }

}