/*
  *
  *  *  Copyright 2014 Orient Technologies LTD (info(at)orientechnologies.com)
  *  *
  *  *  Licensed 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.
  *  *
  *  * For more information: http://www.orientechnologies.com
  *
  */
package com.orientechnologies.orient.core.tx;

import com.orientechnologies.common.comparator.ODefaultComparator;
import com.orientechnologies.orient.core.index.OIndex;
import com.orientechnologies.orient.core.index.OIndexInternal;
import com.orientechnologies.orient.core.index.OIndexManager;

import java.util.NavigableMap;
import java.util.TreeMap;

/**
 * Collects the changes to an index for a certain key
 *
 * @author Luca Garulli (l.garulli--at--orientechnologies.com)
 */
public class OTransactionIndexChanges {

  public enum OPERATION {
    PUT, REMOVE, CLEAR
  }

  public NavigableMap<Object, OTransactionIndexChangesPerKey> changesPerKey = new TreeMap<Object, OTransactionIndexChangesPerKey>(
      ODefaultComparator.INSTANCE);

  public OTransactionIndexChangesPerKey nullKeyChanges = new OTransactionIndexChangesPerKey(null);

  public boolean cleared = false;

  private OIndexInternal<?> resolvedIndex = null;

  public OTransactionIndexChangesPerKey getChangesPerKey(final Object key) {
    if (key == null)
      return nullKeyChanges;

    OTransactionIndexChangesPerKey changes = changesPerKey.get(key);
    if (changes == null) {
      changes = new OTransactionIndexChangesPerKey(key);
      changesPerKey.put(key, changes);
    }

    return changes;
  }

  public void setCleared() {
    changesPerKey.clear();
    nullKeyChanges.clear();

    cleared = true;
  }

  public Object getFirstKey() {
    return changesPerKey.firstKey();
  }

  public Object getLastKey() {
    return changesPerKey.lastKey();
  }

  public Object getLowerKey(Object key) {
    return changesPerKey.lowerKey(key);
  }

  public Object getHigherKey(Object key) {
    return changesPerKey.higherKey(key);
  }

  public Object getCeilingKey(Object key) {
    return changesPerKey.ceilingKey(key);
  }

  public Object getFloorKey(Object key) {
    return changesPerKey.floorKey(key);
  }

  public OIndexInternal<?> resolveAssociatedIndex(String indexName, OIndexManager indexManager) {
    if (resolvedIndex == null) {
      final OIndex<?> index = indexManager.getIndex(indexName);
      if (index != null)
        resolvedIndex = index.getInternal();
    }

    return resolvedIndex;
  }

  public OIndexInternal<?> getAssociatedIndex() {
    return resolvedIndex;
  }
}