/*
 * INESC-ID, Instituto de Engenharia de Sistemas e Computadores Investigação e Desevolvimento em Lisboa
 * Copyright 2013 INESC-ID and/or its affiliates and other
 * contributors as indicated by the @author tags. All rights reserved.
 * See the copyright.txt in the distribution for a full listing of
 * individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 3.0 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.infinispan.dataplacement.c50.tree.node;

import org.infinispan.dataplacement.c50.keyfeature.Feature;
import org.infinispan.dataplacement.c50.keyfeature.FeatureValue;
import org.infinispan.util.logging.Log;
import org.infinispan.util.logging.LogFactory;

import java.util.Map;

/**
 * Type 2 decision tree node: numeric attributes
 *
 * @author Pedro Ruivo
 * @since 5.2
 */
public class Type2Node implements DecisionTreeNode {

   private static final Log log = LogFactory.getLog(Type2Node.class);

   private final int value;
   private final Feature feature;
   private final DecisionTreeNode[] forks;
   private final FeatureValue cut;

   public Type2Node(int value, Feature feature, DecisionTreeNode[] forks, FeatureValue cut) {
      this.value = value;
      this.feature = feature;
      this.cut = cut;
      if (forks == null || forks.length == 0) {
         throw new IllegalArgumentException("Expected a non-null with at least one fork");
      }

      if (forks.length != 3) {
         throw new IllegalArgumentException("Expected 3 forks");
      }

      this.forks = forks;
   }

   @Override
   public DecisionTreeNode find(Map<Feature, FeatureValue> keyFeatures) {
      if (log.isTraceEnabled()) {
         log.tracef("Try to find key [%s] with feature %s", keyFeatures, feature);
      }

      FeatureValue keyValue = keyFeatures.get(feature);
      if (keyValue == null) { //N/A
         if (log.isTraceEnabled()) {
            log.tracef("Feature Not Available...");
         }
         return forks[0];
      }

      if (log.isTraceEnabled()) {
         log.tracef("Comparing key value [%s] with cut %s", keyValue, cut);
      }

      if (keyValue.isLessOrEqualsThan(cut)) {
         if (log.isTraceEnabled()) {
            log.tracef("Next decision tree found. The value is less or equals than cut");
         }
         return forks[1];
      } else if (keyValue.isGreaterThan(cut)) {
         if (log.isTraceEnabled()) {
            log.tracef("Next decision tree found. The value is greater than cut");
         }
         return forks[2];
      }

      throw new IllegalStateException("Expected one value match");
   }

   @Override
   public int getValue() {
      return value;
   }

   @Override
   public int getDeep() {
      int maxDeep = 0;
      for (DecisionTreeNode decisionTreeNode : forks) {
         maxDeep = Math.max(maxDeep, decisionTreeNode.getDeep());
      }
      return maxDeep + 1;
   }
}