package org.kuali.ole.utility.callnumber;
   
   import org.apache.commons.lang.StringUtils;
   import org.slf4j.Logger;
   import org.slf4j.LoggerFactory;
   import org.solrmarc.callnum.AbstractCallNumber;
   import org.solrmarc.callnum.CallNumber;
   
   /**
   * Created with IntelliJ IDEA.
   * User: ?
   * Date: 20/2/13
   * Time: 7:32 PM
   * To change this template use File | Settings | File Templates.
   */
  public class SuDocCallNumber extends AbstractCallNumber implements CallNumber {
      private static final Logger Log = LoggerFactory.getLogger(SuDocCallNumber.class);
      /**
       * regular expression string for complete SuDoc classification
       * Splits the based on continuous numbers and alphabets
       * Ignore any special char and spaces.
       */
      public static final String SUDOC_REGEX = "[^A-Z0-9]+|(?<=[A-Z])(?=[0-9])|(?<=[0-9])(?=[A-Z])";
      protected String shelfKey;
  
      private static SuDocCallNumber ourInstance = null;
  
      public static SuDocCallNumber getInstance() {
          if (null == ourInstance) {
              ourInstance = new SuDocCallNumber();
          }
          return ourInstance;
      }
  
      @Override
      public void parse(String call) {
          try {
              this.rawCallNum = call;
              this.parse();
          } catch (Exception e) {
              Log.error("SuDoc Call Number Exception" + e);
          }
      }
  
      @Override
      public String getShelfKey() {
          return shelfKey;
      }
  
      protected void parse() {
          if (this.rawCallNum != null) {
              this.buildShelfKey();
          }
  
      }
  
      protected void buildShelfKey() {
          String upcaseSuDoccallnum = rawCallNum.toUpperCase();
          StringBuffer callNum = new StringBuffer();
          //split the call number based on numbers and alphabets
          String[] cNumSub = upcaseSuDoccallnum.split(SUDOC_REGEX);
          for (String str : cNumSub) {
              if (StringUtils.isNumeric(str)) {   // numbers
                  // append zeros to sort Ordinal
                  str = StringUtils.leftPad(str, 5, "0"); // constant length 5
                  callNum.append(str);
                  callNum.append(" ");
              } else {                     // alphabets
                  // append spaces to sort Lexicographic
                  str = StringUtils.rightPad(str, 5);  // constant length 5
                  callNum.append(str);
                  callNum.append(" ");
              }
          }
          shelfKey = callNum.toString().trim();
      }
  }