package rescuecore2.log;

import static rescuecore2.misc.EncodingTools.writeInt32;
import static rescuecore2.misc.EncodingTools.readInt32;

import java.io.OutputStream;
import java.io.InputStream;
import java.io.IOException;

import rescuecore2.worldmodel.ChangeSet;

/**
   An updates record.
*/
public class UpdatesRecord implements LogRecord {
    private int time;
    private ChangeSet changes;

    /**
       Construct a new UpdatesRecord.
       @param time The timestep of this updates record.
       @param changes The set of changes.
     */
    public UpdatesRecord(int time, ChangeSet changes) {
        this.time = time;
        this.changes = changes;
    }

    /**
       Construct a new UpdatesRecord and read data from an InputStream.
       @param in The InputStream to read from.
       @throws IOException If there is a problem reading the stream.
       @throws LogException If there is a problem reading the log record.
     */
    public UpdatesRecord(InputStream in) throws IOException, LogException {
        read(in);
    }

    @Override
    public RecordType getRecordType() {
        return RecordType.UPDATES;
    }

    @Override
    public void write(OutputStream out) throws IOException {
        writeInt32(time, out);
        changes.write(out);
    }

    @Override
    public void read(InputStream in) throws IOException, LogException {
        time = readInt32(in);
        changes = new ChangeSet();
        changes.read(in);
    }

    /**
       Get the timestamp for this record.
       @return The timestamp.
    */
    public int getTime() {
        return time;
    }

    /**
       Get the entity updates.
       @return The changes.
     */
    public ChangeSet getChangeSet() {
        return changes;
    }
}