/**
 * Copyright 2013-2014 Recruit Technologies Co., Ltd. and contributors
 * (see CONTRIBUTORS.md)
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may
 * not use this file except in compliance with the License.  A copy of the
 * License is distributed with this work in the LICENSE.md file.  You may
 * also obtain a copy of the License from
 *
 *     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.gennai.gungnir.topology.operator;

import static org.gennai.gungnir.GungnirConst.*;

import org.gennai.gungnir.topology.ConditionEvaluator;
import org.gennai.gungnir.tuple.Condition;
import org.gennai.gungnir.tuple.GungnirTuple;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

@Operator.Description(name = "FILTER", parameterNames = "condition")
public class FilterOperator extends BaseOperator implements ExecOperator {

  private static final long serialVersionUID = SERIAL_VERSION_UID;
  private static final Logger LOG = LoggerFactory.getLogger(FilterOperator.class);

  private Condition condition;

  public FilterOperator(Condition condition) {
    super();
    this.condition = condition;
  }

  private FilterOperator(FilterOperator c) {
    super(c);
    this.condition = c.condition;
  }

  @Override
  protected void prepare() {
  }

  @Override
  public void execute(GungnirTuple tuple) {
    if (LOG.isDebugEnabled()) {
      LOG.debug("execute({} {}) {}", getContext().getTopologyId(), getName(), tuple);
    }

    if (ConditionEvaluator.isKeep(condition, tuple)) {
      dispatch(tuple.getTupleValues());
    }
  }

  @Override
  public FilterOperator clone() {
    return new FilterOperator(this);
  }
}