package org.paneris.bibliomania.fti;
   
   import java.util.Enumeration;
   import java.util.Vector;
   
   import org.melati.util.PagedEnumeration;
   
   import com.sleepycat.db.DatabaseException;
   
  public class ScoredHitTextsEnumeration implements PagedEnumeration {
    private ContextSearchResults results;
  
    private int pageStart, pageSize, requestedPageSize;
  
    // private HitText hitText = null;
    private boolean totalCountIsMinimum;
  
    private Enumeration us;
  
    public ScoredHitTextsEnumeration(ContextSearchResults resultsP,
        Score.Hit[] scores, int pageStart, int requestedPageSize, int hitsPerText)
        throws FTIException {
      try {
        this.results = resultsP;
        this.pageStart = pageStart = Math.max(pageStart, 1);
        this.requestedPageSize = requestedPageSize;
  
        int h = 0;
        int areaCount = 0, areasInThisText = 0;
        while (areaCount + 1 < pageStart) {
          if (results.nextArea() == null || areasInThisText >= hitsPerText) {
            if (h >= scores.length)
              break;
            results.gotoText(scores[h++].textID);
            areasInThisText = 0;
          } else {
            ++areaCount;
            ++areasInThisText;
          }
        }
  
        Vector texts = new Vector();
        int a;
        for (a = 0; a < requestedPageSize && h < scores.length; ++h) {
          results.gotoText(scores[h].textID);
  
          // Just make sure the text exists---we let old indexings hang around
          // rather than expend effort deleting them
  
          if (results.currentText() != null) {
            HitText text = new HitText(scores[h].score, results, Math.min(
                requestedPageSize - a, hitsPerText - areasInThisText));
            areasInThisText = 0;
            texts.addElement(text);
            a += text.areas;
          }
        }
  
        totalCountIsMinimum = a == requestedPageSize;
        pageSize = a;
  
        us = texts.elements();
      } catch (DatabaseException e) {
        throw new FTIException(e);
      }
    }
  
    // 
    // -------------
    // Enumeration
    // -------------
    // 
  
    public boolean hasMoreElements() {
      return us.hasMoreElements();
    }
  
    public Object nextElement() {
      return us.nextElement();
    }
  
    // 
    // -----------------
    // PageEnumeration
    // -----------------
    // 
  
    public int getPageStart() {
      return pageStart;
    }
  
    public int getPageSize() {
      return pageSize;
    }
  
    public int getPageEnd() {
      return pageStart + pageSize - 1;
    }
  
   public int getTotalCount() {
     return getPageEnd();
   }
 
   public boolean getTotalCountIsMinimum() {
     return totalCountIsMinimum;
   }
 
   public Integer getPrevPageStart() {
     int it = pageStart - requestedPageSize;
     return it < 0 ? null : new Integer(it);
   }
 
   public Integer getNextPageStart() {
     return totalCountIsMinimum ? new Integer(pageStart + requestedPageSize)
         : null;
   }
 
   public int getCurrentPosition() {
     throw new RuntimeException("No one else has ever called this method.");
   }
 
   public int getNextPosition() {
     throw new RuntimeException("No one else has ever called this method.");
   }
 
   public Vector getPages() {
     throw new RuntimeException("No one else has ever called this method.");
   }
 
   public boolean nextElementOnThisPage() {
     throw new RuntimeException("No one else has ever called this method.");
   }
 }