/*
 * 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.streampipes.processors.transformation.jvm.processor.stringoperator.state;

import org.apache.streampipes.commons.exceptions.SpRuntimeException;
import org.apache.streampipes.extensions.api.pe.context.EventProcessorRuntimeContext;
import org.apache.streampipes.extensions.api.pe.routing.SpOutputCollector;
import org.apache.streampipes.model.DataProcessorType;
import org.apache.streampipes.model.graph.DataProcessorDescription;
import org.apache.streampipes.model.runtime.Event;
import org.apache.streampipes.model.schema.PropertyScope;
import org.apache.streampipes.sdk.builder.ProcessingElementBuilder;
import org.apache.streampipes.sdk.builder.StreamRequirementsBuilder;
import org.apache.streampipes.sdk.extractor.ProcessingElementParameterExtractor;
import org.apache.streampipes.sdk.helpers.EpProperties;
import org.apache.streampipes.sdk.helpers.EpRequirements;
import org.apache.streampipes.sdk.helpers.Labels;
import org.apache.streampipes.sdk.helpers.Locales;
import org.apache.streampipes.sdk.helpers.OutputStrategies;
import org.apache.streampipes.sdk.utils.Assets;
import org.apache.streampipes.vocabulary.SPSensor;
import org.apache.streampipes.wrapper.params.compat.ProcessorParams;
import org.apache.streampipes.wrapper.standalone.StreamPipesDataProcessor;

import com.google.common.collect.Lists;

import java.util.List;

public class StringToStateProcessor extends StreamPipesDataProcessor {

  public static final String STRING_STATE_FIELD = "string_state_field";

  public static final String CURRENT_STATE = "current_state";

  private List<String> stateFields;

  @Override
  public DataProcessorDescription declareModel() {
    return ProcessingElementBuilder.create(
            "org.apache.streampipes.processors.transformation.jvm.processor.stringoperator.state")
        .category(DataProcessorType.STRING_OPERATOR)
        .withLocales(Locales.EN)
        .withAssets(Assets.DOCUMENTATION, Assets.ICON)
        .requiredStream(StreamRequirementsBuilder.create()
            .requiredPropertyWithNaryMapping(EpRequirements.stringReq(), Labels.withId(STRING_STATE_FIELD),
                PropertyScope.NONE)
            .build())
        .outputStrategy(OutputStrategies.append(
            EpProperties.listStringEp(Labels.withId(CURRENT_STATE), CURRENT_STATE, SPSensor.STATE)
        ))
        .build();
  }

  @Override
  public void onInvocation(ProcessorParams parameters,
                           SpOutputCollector spOutputCollector,
                           EventProcessorRuntimeContext runtimeContext) throws SpRuntimeException {
    ProcessingElementParameterExtractor extractor = parameters.extractor();
    this.stateFields = extractor.mappingPropertyValues(STRING_STATE_FIELD);
  }

  @Override
  public void onEvent(Event event, SpOutputCollector collector) throws SpRuntimeException {
    List<String> states = Lists.newArrayList();

    for (String stateField : stateFields) {
      states.add(event.getFieldBySelector(stateField).getAsPrimitive().getAsString());
    }

    event.addField(CURRENT_STATE, states.toArray());
    collector.collect(event);
  }

  @Override
  public void onDetach() throws SpRuntimeException {

  }
}
