/*
    * ObjectLab, http://www.objectlab.co.uk/open is supporting FlatPack.
    *
    * Based in London, we are world leaders in the design and development
    * of bespoke applications for the securities financing markets.
    *
    * <a href="http://www.objectlab.co.uk/open">Click here to learn more</a>
    *           ___  _     _           _   _          _
    *          / _ \| |__ (_) ___  ___| |_| |    __ _| |__
   *         | | | | '_ \| |/ _ \/ __| __| |   / _` | '_ \
   *         | |_| | |_) | |  __/ (__| |_| |__| (_| | |_) |
   *          \___/|_.__// |\___|\___|\__|_____\__,_|_.__/
   *                   |__/
   *
   *                     www.ObjectLab.co.uk
   *
   * $Id: ColorProvider.java 74 2006-10-24 22:19:05Z benoitx $
   *
   * Copyright 2006 the original author or authors.
   *
   * Licensed 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 net.sf.flatpack.ordering;
  
  import java.text.ParseException;
  import java.text.SimpleDateFormat;
  import java.util.ArrayList;
  import java.util.Calendar;
  import java.util.Comparator;
  import java.util.Date;
  import java.util.GregorianCalendar;
  import java.util.List;
  import java.util.Locale;
  
  import net.sf.flatpack.Parser;
  import net.sf.flatpack.structure.Row;
  import net.sf.flatpack.util.FPConstants;
  import net.sf.flatpack.util.ParserUtils;
  import net.sf.flatpack.xml.MetaData;
  
  /**
   * @author paul zepernick
   *
   * resorts an array of objects. Arrays get sorted by OrderElements. Right now,
   * this class will only handle string comparisons.
   *
   * @version 2.0
   */
  public class OrderBy implements Comparator<Row> {
      /** collection of order elements to sort by */
      private final List<OrderColumn> orderbys = new ArrayList<>();
  
      private MetaData metaData;
  
      private Parser parser;
  
      /**
       * Adds an order element to the sort.
       *
       * @param oc -
       *            OrderColumn
       */
      public void addOrderColumn(final OrderColumn oc) {
          orderbys.add(oc);
      }
  
      /**
       * overridden from the Comparator class.
       *
       * Performs the sort
       *
       * @return int
       */
      @Override
      public int compare(final Row row0, final Row row1) {
          int result = 0;
  
          for (int i = 0; i < orderbys.size(); i++) {
              final OrderColumn oc = orderbys.get(i);
              // null indicates "detail" record which is what the parser assigns
              // to <column> 's setup outside of <record> elements
              final String mdkey0 = row0.getMdkey() == null ? FPConstants.DETAIL_ID : row0.getMdkey();
              final String mdkey1 = row1.getMdkey() == null ? FPConstants.DETAIL_ID : row1.getMdkey();
  
              // shift all non detail records to the bottom of the DataSet
              if (!mdkey0.equals(FPConstants.DETAIL_ID) && !mdkey1.equals(FPConstants.DETAIL_ID)) {
                  // keep headers / trailers in the same order at the bottom of
                  // the DataSet
                  return 0;
             } else if (!mdkey0.equals(FPConstants.DETAIL_ID) || !mdkey1.equals(FPConstants.DETAIL_ID)) {
                 return !mdkey0.equals(FPConstants.DETAIL_ID) ? 1 : 0;
             }
 
             result = compareCol(row0, row1, oc);
 
             // if it is = 0 then the primary sort is done, and it can start the
             // secondary sorts
             if (result != 0) {
                 break;
             }
         }
 
         return result;
     }
 
     private int compareCol(final Row row0, final Row row1, final OrderColumn oc) {
         int result;
         // convert to one type of case so the comparator does not take case
         // into account when sorting
         Comparable comp0 = null;
         Comparable comp1 = null;
         final String str0 = row0
                 .getValue(ParserUtils.getColumnIndex(row0.getMdkey(), metaData, oc.getColumnName(), parser.isColumnNamesCaseSensitive()))
                 .toLowerCase(Locale.getDefault());
         final String str1 = row1
                 .getValue(ParserUtils.getColumnIndex(row1.getMdkey(), metaData, oc.getColumnName(), parser.isColumnNamesCaseSensitive()))
                 .toLowerCase(Locale.getDefault());
         switch (oc.getSelectedColType()) {
         case OrderColumn.COLTYPE_NUMERIC:
             comp0 = Double.valueOf(ParserUtils.stripNonDoubleChars(str0));
             comp1 = Double.valueOf(ParserUtils.stripNonDoubleChars(str1));
             break;
         case OrderColumn.COLTYPE_DATE:
             final SimpleDateFormat sdf = new SimpleDateFormat(oc.getDateFormatPattern());
             try {
                 comp0 = sdf.parse(str0);
             } catch (final ParseException e) {
                 comp0 = getBadDateDefault();
 
             }
 
             try {
                 comp1 = sdf.parse(str1);
             } catch (final ParseException e) {
                 comp1 = getBadDateDefault();
             }
             break;
         case OrderColumn.COLTYPE_STRING:
         default:
             comp0 = str0;
             comp1 = str1;
             break;
         }
 
         // multiply by the sort indicator to get a ASC or DESC result
         result = comp0.compareTo(comp1) * oc.getSortIndicator();
         return result;
     }
 
     private Date getBadDateDefault() {
         final Calendar defaultBadDt = new GregorianCalendar();
         defaultBadDt.set(Calendar.MONTH, 1);
         defaultBadDt.set(Calendar.YEAR, 1900);
         defaultBadDt.set(Calendar.DAY_OF_MONTH, 1);
         return defaultBadDt.getTime();
     }
 
     /**
      * @param metaData the metaData to set
      */
     public void setMetaData(final MetaData metaData) {
         this.metaData = metaData;
     }
 
     /**
      * @param parser the parser to set
      */
     public void setParser(final Parser parser) {
         this.parser = parser;
     }
 
 }