content: /**
   * Copyright 2006 DFKI GmbH.
   * All Rights Reserved.  Use is subject to license terms.
   * <p/>
   * This file is part of MARY TTS.
   * <p/>
   * MARY TTS 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, version 3 of the License.
   * <p/>
   * This program 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.
   * <p/>
   * You should have received a copy of the GNU Lesser General Public License
   * along with this program.  If not, see <http://www.gnu.org/licenses/>.
   */
  package marytts.unitselection.select;
  
  import android.util.Log;
  
  import java.util.ArrayList;
  import java.util.List;
  
  import marytts.datatypes.MaryXML;
  import marytts.exceptions.SynthesisException;
  import marytts.server.Mary;
  import marytts.unitselection.data.UnitDatabase;
  import marytts.unitselection.select.viterbi.Viterbi;
  import mf.org.w3c.dom.Element;
  import mf.org.w3c.dom.NodeList;
  
  //import org.apache.log4j.Logger;
  
  
  /**
   * Selects the units for an utterance
   *
   * @author Marc Schr&ouml;der
   */
  public class UnitSelector {
      protected UnitDatabase database;
      // protected Logger logger;
      protected float targetCostWeight;
      protected float sCostWeight = -1;
      protected int beamSize;
  
      /**
       * Initialise the unit selector. Need to call load() separately.
       *
       * @see #load(UnitDatabase)
       */
      public UnitSelector() throws Exception {
          //logger = MaryUtils.getLogger(this.getClass());
      }
  
      public static String getPhoneSymbol(Element segmentOrBoundary) {
          String phone;
          if (segmentOrBoundary.getTagName().equals(MaryXML.PHONE)) {
              phone = segmentOrBoundary.getAttribute("p");
          } else {
              assert segmentOrBoundary.getTagName().equals(MaryXML.BOUNDARY)
                      : "Expected boundary element, but got " + segmentOrBoundary.getTagName();
              // TODO: how can we know the silence symbol here?
              phone = "_";
          }
          return phone;
      }
  
      public void load(UnitDatabase unitDatabase, float targetCostWeight, int beamSize) {
          this.database = unitDatabase;
          this.targetCostWeight = targetCostWeight;
          this.beamSize = beamSize;
      }
  
      public void load(UnitDatabase unitDatabase, float targetCostWeight, float sCostWeight, int beamSize) {
          this.database = unitDatabase;
          this.targetCostWeight = targetCostWeight;
          this.sCostWeight = sCostWeight;
          this.beamSize = beamSize;
      }
  
      /**
       * Select the units for the targets in the given
       * list of tokens and boundaries. Collect them in a list and return it.
       *
       * @param tokensAndBoundaries the token and boundary MaryXML elements representing
       *                            an utterance.
       * @param voice               the voice with which to synthesize
       * @param db                  the database of the voice
       * @param unitNamer           a unitNamer
       * @return a list of SelectedUnit objects
       * @throws IllegalStateException if no path for generating the target utterance
       *                               could be found
       */
      public List<SelectedUnit> selectUnits(List<Element> tokensAndBoundaries,
                                            marytts.modules.synthesis.Voice voice)
              throws SynthesisException {
          long time = System.currentTimeMillis();
  
          List<Element> segmentsAndBoundaries = new ArrayList<Element>();
          for (Element tOrB : tokensAndBoundaries) {
              if (tOrB.getTagName().equals(MaryXML.BOUNDARY)) {
                  segmentsAndBoundaries.add(tOrB);
              } else {
                  assert tOrB.getTagName().equals(MaryXML.TOKEN) : "Expected token, got " + tOrB.getTagName();
                  NodeList segs = tOrB.getElementsByTagName(MaryXML.PHONE);
                  for (int i = 0, max = segs.getLength(); i < max; i++) {
                      segmentsAndBoundaries.add((Element) segs.item(i));
                  }
              }
          }
  
          List<Target> targets = createTargets(segmentsAndBoundaries);
          // compute target features for each target in the chain
          TargetCostFunction tcf = database.getTargetCostFunction();
          for (Target target : targets) {
              tcf.computeTargetFeatures(target);
          }
  
          Viterbi viterbi;
          //Select the best candidates using Viterbi and the join cost function.
          if (sCostWeight < 0) {
              viterbi = new Viterbi(targets, database, targetCostWeight, beamSize);
          } else {
              viterbi = new Viterbi(targets, database, targetCostWeight, sCostWeight, beamSize);
          }
  
          viterbi.apply();
          List<SelectedUnit> selectedUnits = viterbi.getSelectedUnits();
          // If you can not associate the candidate units in the best path
          // with the items in the segment relation, there is no best path
          if (selectedUnits == null) {
              throw new IllegalStateException("Viterbi: can't find path");
          }
          long newtime = System.currentTimeMillis() - time;
          Log.d(Mary.LOG, "Selection took " + newtime + " milliseconds");
          return selectedUnits;
      }
  
      /**
       * Create the list of targets from the XML elements to synthesize.
       *
       * @param segmentsAndBoundaries a list of MaryXML phone and boundary elements
       * @return a list of Target objects
       */
      protected List<Target> createTargets(List<Element> segmentsAndBoundaries) {
          List<Target> targets = new ArrayList<Target>();
          for (Element sOrB : segmentsAndBoundaries) {
              String phone = getPhoneSymbol(sOrB);
              targets.add(new Target(phone, sOrB));
          }
          return targets;
      }
  
  
  }
  