/**
    *
    * 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.hadoop.hbase.filter;
  
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.List;
  import java.util.Objects;
  
  import com.google.protobuf.InvalidProtocolBufferException;
  import org.apache.hadoop.hbase.Cell;
  import org.apache.hadoop.hbase.KeyValue;
  import org.apache.hadoop.hbase.KeyValueUtil;
  import org.apache.hadoop.hbase.classification.InterfaceAudience;
  import org.apache.hadoop.hbase.classification.InterfaceStability;
  import org.apache.hadoop.hbase.exceptions.DeserializationException;
  import org.apache.hadoop.hbase.protobuf.ProtobufUtil;
  import org.apache.hadoop.hbase.protobuf.generated.FilterProtos;
  
  /**
   * Implementation of {@link Filter} that represents an ordered List of Filters which will be
   * evaluated with a specified boolean operator {@link Operator#MUST_PASS_ALL} (<code>AND</code>) or
   * {@link Operator#MUST_PASS_ONE} (<code>OR</code>). Since you can use Filter Lists as children of
   * Filter Lists, you can create a hierarchy of filters to be evaluated. <br>
   * {@link Operator#MUST_PASS_ALL} evaluates lazily: evaluation stops as soon as one filter does not
   * include the KeyValue. <br>
   * {@link Operator#MUST_PASS_ONE} evaluates non-lazily: all filters are always evaluated. <br>
   * Defaults to {@link Operator#MUST_PASS_ALL}.
   */
  @InterfaceAudience.Public
  @InterfaceStability.Stable
  final public class FilterList extends Filter {
  
    /** set operator */
    @InterfaceAudience.Public
    @InterfaceStability.Stable
    public enum Operator {
      /** !AND */
      MUST_PASS_ALL,
      /** !OR */
      MUST_PASS_ONE
    }
  
    private Operator operator = Operator.MUST_PASS_ALL;
    private FilterListBase filterListBase;
  
    /**
     * Constructor that takes a set of {@link Filter}s and an operator.
     * @param operator Operator to process filter set with.
     * @param filters Set of row filters.
     */
    public FilterList(final Operator operator, final List<Filter> filters) {
      if (operator == Operator.MUST_PASS_ALL) {
        filterListBase = new FilterListWithAND(filters);
      } else if (operator == Operator.MUST_PASS_ONE) {
        filterListBase = new FilterListWithOR(filters);
      } else {
        throw new IllegalArgumentException("Invalid operator: " + operator);
      }
      this.operator = operator;
    }
  
    /**
     * Constructor that takes a set of {@link Filter}s. The default operator MUST_PASS_ALL is assumed.
     * All filters are cloned to internal list.
     * @param filters list of filters
     */
    public FilterList(final List<Filter> filters) {
      this(Operator.MUST_PASS_ALL, filters);
    }
  
    /**
     * Constructor that takes a var arg number of {@link Filter}s. The default operator MUST_PASS_ALL
     * is assumed.
     * @param filters
     */
    public FilterList(final Filter... filters) {
      this(Operator.MUST_PASS_ALL, Arrays.asList(filters));
    }
  
    /**
    * Constructor that takes an operator.
    * @param operator Operator to process filter set with.
    */
   public FilterList(final Operator operator) {
     this(operator, new ArrayList<Filter>());
   }
 
   /**
    * Constructor that takes a var arg number of {@link Filter}s and an operator.
    * @param operator Operator to process filter set with.
    * @param filters Filters to use
    */
   public FilterList(final Operator operator, final Filter... filters) {
     this(operator, Arrays.asList(filters));
   }
 
   /**
    * Get the operator.
    * @return operator
    */
   public Operator getOperator() {
     return operator;
   }
 
   /**
    * Get the filters.
    * @return filters
    */
   public List<Filter> getFilters() {
     return filterListBase.getFilters();
   }
 
   public int size() {
     return filterListBase.size();
   }
 
   public void addFilter(List<Filter> filters) {
     filterListBase.addFilterLists(filters);
   }
 
   /**
    * Add a filter.
    * @param filter another filter
    */
   public void addFilter(Filter filter) {
     addFilter(Collections.singletonList(filter));
   }
 
   @Override
   public void reset() throws IOException {
     filterListBase.reset();
   }
 
   @Override
   public boolean filterRowKey(byte[] rowKey, int offset, int length) throws IOException {
     return filterListBase.filterRowKey(rowKey, offset, length);
   }
 
   @Override
   public boolean filterAllRemaining() throws IOException {
     return filterListBase.filterAllRemaining();
   }
 
   @Override
   public Cell transformCell(Cell c) throws IOException {
     return filterListBase.transformCell(c);
   }
 
   /**
    * WARNING: please to not override this method. Instead override {@link #transformCell(Cell)}.
    * When removing this, its body should be placed in transformCell. This is for transition from
    * 0.94 -&gt; 0.96
    */
   @Deprecated
   @Override
   public KeyValue transform(KeyValue v) throws IOException {
     return KeyValueUtil.ensureKeyValue(transformCell((Cell) v));
   }
 
   @Override
   public ReturnCode filterKeyValue(Cell c) throws IOException {
     return filterListBase.filterKeyValue(c);
   }
 
   /**
    * Filters that never filter by modifying the returned List of Cells can inherit this
    * implementation that does nothing. {@inheritDoc}
    */
   @Override
   public void filterRowCells(List<Cell> cells) throws IOException {
     filterListBase.filterRowCells(cells);
   }
 
   @Override
   public boolean hasFilterRow() {
     return filterListBase.hasFilterRow();
   }
 
   @Override
   public boolean filterRow() throws IOException {
     return filterListBase.filterRow();
   }
 
   /**
    * @return The filter serialized using pb
    */
   @Override
   public byte[] toByteArray() throws IOException {
     FilterProtos.FilterList.Builder builder = FilterProtos.FilterList.newBuilder();
     builder.setOperator(FilterProtos.FilterList.Operator.valueOf(operator.name()));
     ArrayList<Filter> filters = filterListBase.getFilters();
     for (int i = 0, n = filters.size(); i < n; i++) {
       builder.addFilters(ProtobufUtil.toFilter(filters.get(i)));
     }
     return builder.build().toByteArray();
   }
 
   /**
    * @param pbBytes A pb serialized {@link FilterList} instance
    * @return An instance of {@link FilterList} made from <code>bytes</code>
    * @throws DeserializationException
    * @see #toByteArray
    */
   public static FilterList parseFrom(final byte[] pbBytes) throws DeserializationException {
     FilterProtos.FilterList proto;
     try {
       proto = FilterProtos.FilterList.parseFrom(pbBytes);
     } catch (InvalidProtocolBufferException e) {
       throw new DeserializationException(e);
     }
 
     List<Filter> rowFilters = new ArrayList<Filter>(proto.getFiltersCount());
     try {
       List<FilterProtos.Filter> filtersList = proto.getFiltersList();
       for (int i = 0, n = filtersList.size(); i < n; i++) {
         rowFilters.add(ProtobufUtil.toFilter(filtersList.get(i)));
       }
     } catch (IOException ioe) {
       throw new DeserializationException(ioe);
     }
     return new FilterList(Operator.valueOf(proto.getOperator().name()), rowFilters);
   }
 
   /**
    * @param other
    * @return true if and only if the fields of the filter that are serialized are equal to the
    *         corresponding fields in other. Used for testing.
    */
   @Override
   boolean areSerializedFieldsEqual(Filter other) {
     if (other == this) return true;
     if (!(other instanceof FilterList)) return false;
 
     FilterList o = (FilterList) other;
     return this.getOperator().equals(o.getOperator())
         && ((this.getFilters() == o.getFilters()) || this.getFilters().equals(o.getFilters()));
   }
 
   @Override
   @Deprecated
   public KeyValue getNextKeyHint(KeyValue currentKV) throws IOException {
     return KeyValueUtil.ensureKeyValue(getNextCellHint((Cell) currentKV));
   }
 
   @Override
   public Cell getNextCellHint(Cell currentCell) throws IOException {
     return this.filterListBase.getNextCellHint(currentCell);
   }
 
   @Override
   public boolean isFamilyEssential(byte[] name) throws IOException {
     return this.filterListBase.isFamilyEssential(name);
   }
 
   @Override
   public void setReversed(boolean reversed) {
     this.reversed = reversed;
     this.filterListBase.setReversed(reversed);
   }
 
   @Override
   public boolean isReversed() {
     assert this.reversed == this.filterListBase.isReversed();
     return this.reversed;
   }
 
   /**
    * @param maxFilters ignored
    * @deprecated
    */
   @Deprecated
   public String toString(int maxFilters) {
     return this.filterListBase.toString();
   }
 
   @Override
   public String toString() {
     return this.filterListBase.toString();
   }
 
   @Override
   public boolean equals(Object obj) {
     return obj instanceof Filter && areSerializedFieldsEqual((Filter) obj);
   }
 
   @Override
   public int hashCode() {
     return Objects.hash(getOperator(), getFilters());
   }
 }