/*
 * 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.samoa.apex.topology.impl;

import java.util.HashMap;
import java.util.Map;

import org.apache.samoa.core.EntranceProcessor;
import org.apache.samoa.core.Processor;
import org.apache.samoa.topology.ComponentFactory;
import org.apache.samoa.topology.EntranceProcessingItem;
import org.apache.samoa.topology.IProcessingItem;
import org.apache.samoa.topology.ProcessingItem;
import org.apache.samoa.topology.Stream;
import org.apache.samoa.topology.Topology;

/**
 * Component factory implementation for samoa-apex
 */
public final class ApexComponentFactory implements ComponentFactory {

  private final Map<String, Integer> processorList;

  public ApexComponentFactory() {
    processorList = new HashMap<>();
  }

  @Override
  public ProcessingItem createPi(Processor processor) {
    return new ApexProcessingItem(processor, this.getComponentName(processor.getClass()), 1);
  }

  @Override
  public ProcessingItem createPi(Processor processor, int parallelism) {
    return new ApexProcessingItem(processor, this.getComponentName(processor.getClass()), parallelism);
  }

  @Override
  public EntranceProcessingItem createEntrancePi(EntranceProcessor processor) {
    return new ApexEntranceProcessingItem(processor, this.getComponentName(processor.getClass()));
  }

  @Override
  public Stream createStream(IProcessingItem sourcePi) {
    ApexTopologyNode apexCompatiblePi = (ApexTopologyNode) sourcePi;
    ApexStream stream = apexCompatiblePi.createStream();
    return stream;
  }

  @Override
  public Topology createTopology(String topoName) {
    return new ApexTopology(topoName);
  }

  private String getComponentName(Class<? extends Processor> clazz) {
    StringBuilder componentName = new StringBuilder(clazz.getCanonicalName());
    String key = componentName.toString();
    Integer index;

    if (!processorList.containsKey(key)) {
      index = 1;
    } else {
      index = processorList.get(key) + 1;
    }

    processorList.put(key, index);

    componentName.append('_');
    componentName.append(index);

    return componentName.toString();
  }
}