/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.cassandra.db.commitlog;


import java.io.IOException;
import java.util.List;
import java.util.Map;

public interface CommitLogMBean
{
    /**
     *  Command to execute to archive a commitlog segment.  Blank to disabled.
     */
    public String getArchiveCommand();

    /**
     * Command to execute to make an archived commitlog live again
     */
    public String getRestoreCommand();

    /**
     * Directory to scan the recovery files in
     */
    public String getRestoreDirectories();

    /**
     * Restore mutations created up to and including this timestamp in GMT
     * There are only three different formats to express three time precisions:
     * Seconds, Milliseconds, and Microseconds.
     * Seconds format: yyyy:MM:dd HH:mm:ss (2012:04:31 20:43:12)
     * Milliseconds format: yyyy:MM:dd HH:mm:ss.SSS (2012:04:31 20:43:12.633)
     * Microseconds format: yyyy:MM:dd HH:mm:ss.SSSSSS (2012:04:31 20:43:12.633222)
     *
     * Recovery will continue through the segment when the first client-supplied
     * timestamp greater than this time is encountered, but only mutations less than
     * or equal to this timestamp will be applied.
     */
    public long getRestorePointInTime();

    /**
     * get precision of the timestamp used in the restore (MILLISECONDS, MICROSECONDS, ...)
     * to determine if passed the restore point in time.
     */
    public String getRestorePrecision();

    /**
     * Recover a single file.
     */
    public void recover(String path) throws IOException;

    /**
     * @return file names (not full paths) of active commit log segments (segments containing unflushed data)
     */
    public List<String> getActiveSegmentNames();

    /**
     * @return Files which are pending for archival attempt.  Does NOT include failed archive attempts.
     */
    public List<String> getArchivingSegmentNames();

    /**
     * @return The size of the mutations in all active commit log segments (uncompressed).
     */
    public long getActiveContentSize();

    /**
     * @return The space taken on disk by the commit log (compressed).
     */
    public long getActiveOnDiskSize();

    /**
     * @return A map between active log segments and the compression ratio achieved for each.
     */
    public Map<String, Double> getActiveSegmentCompressionRatios();
}
