/*
 * 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.solr.handler;

import java.net.URI;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
import java.util.Optional;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import com.google.common.base.Preconditions;

class OldBackupDirectory implements Comparable<OldBackupDirectory> {
  private static final Pattern dirNamePattern = Pattern.compile("^snapshot[.](.*)$");

  private URI basePath;
  private String dirName;
  private Optional<Date> timestamp;

  public OldBackupDirectory(URI basePath, String dirName) {
    this.dirName = Preconditions.checkNotNull(dirName);
    this.basePath = Preconditions.checkNotNull(basePath);
    Matcher m = dirNamePattern.matcher(dirName);
    if (m.find()) {
      try {
        this.timestamp = Optional.of(new SimpleDateFormat(SnapShooter.DATE_FMT, Locale.ROOT).parse(m.group(1)));
      } catch (ParseException e) {
        this.timestamp = Optional.empty();
      }
    }
  }

  public URI getPath() {
    return this.basePath.resolve(dirName);
  }

  public String getDirName() {
    return dirName;
  }

  public Optional<Date> getTimestamp() {
    return timestamp;
  }

  @Override
  public int compareTo(OldBackupDirectory that) {
    if(this.timestamp.isPresent() && that.timestamp.isPresent()) {
      return that.timestamp.get().compareTo(this.timestamp.get());
    }
    // Use absolute value of path in case the time-stamp is missing on either side.
    return that.getPath().compareTo(this.getPath());
  }
}
