Snapshot.java

package com.github.ruediste1.btrbck.dom;

import java.nio.file.Path;
import java.util.Comparator;
import java.util.UUID;

import org.joda.time.DateTime;
import org.joda.time.format.ISODateTimeFormat;

/**
 * Represents a snapshot of the working directory of a {@link Stream}.
 */
public class Snapshot {
    public static final Comparator<Snapshot> COMPARATOR_NR = new Comparator<Snapshot>() {

        @Override
        public int compare(Snapshot o1, Snapshot o2) {
            return Integer.compare(o1.nr, o2.nr);
        }
    };

    /**
     * Number of the snapshot. The next snapshot number is determined by the
     * length of the {@link VersionHistory} of the {@link Stream}
     */
    public int nr;

    /**
     * Instant the snapshot has been taken
     */
    public DateTime date;

    /**
     * {@link Stream} the snapshot belongs to
     */
    public Stream stream;

    public UUID senderStreamId;

    public Snapshot() {}

    public Snapshot(int nr, DateTime date, Stream stream) {
        super();
        this.nr = nr;
        this.date = date;
        this.stream = stream;
    }

    public Path getSnapshotDir() {
        return stream.getSnapshotsDir().resolve(getSnapshotName());
    }

    public String getSnapshotName() {
        return String.format("%d_%s", nr,
                date.toString(ISODateTimeFormat.dateTime()));
    }

    @Override
    public String toString() {
        return getSnapshotName();
    }

    public static Snapshot parse(Stream stream, String name) {
        Snapshot snapshot = new Snapshot();
        snapshot.stream = stream;
        int idx = name.indexOf("_");
        snapshot.date = ISODateTimeFormat.dateTimeParser().withOffsetParsed()
                .parseDateTime(name.substring(idx + 1));
        snapshot.nr = Integer.parseInt(name.substring(0, idx));
        return snapshot;
    }
}