package org.jscsi.target.settings.entry;
   
   
   import org.jscsi.target.TargetServer;
   import org.jscsi.target.settings.BooleanResultFunction;
   import org.jscsi.target.settings.KeySet;
   import org.jscsi.target.settings.NegotiationStatus;
   import org.jscsi.target.settings.NegotiationType;
   import org.jscsi.target.settings.TextParameter;
  
  
  /**
   * An {@link Entry} sub-class for boolean parameters.
   * <p>
   * During text parameter negotiation, boolean values are encoded as <code>Yes</code> and <code>No</code>, meaning
   * <code>true</code> and <code>false</code>, respectively.
   * <p>
   * The default or negotiated value can be accessed via the {@link #getBooleanValue()} method.
   * 
   * @see Entry
   * @author Andreas Ergenzinger
   */
  public final class BooleanEntry extends Entry {
  
      private final boolean negotiationValue;
      private final BooleanResultFunction resultFunction;
  
      /**
       * The {@link BooleanEntry} constructor.
       * 
       * @param keySet contains all relevant keys
       * @param use determines under which circumstances the parameter may be negotiated
       * @param negotiationStatus indicates whether there is a default value or if the parameter must be negotiated
       * @param negotiationValue together with the <i>resultFunction</i> parameter this value indicates the values
       *            supported by the jSCSI Target
       * @param resultFunction the result function to use during negotiations
       * @param defaultValue the default value or <code>null</code>
       */
      public BooleanEntry (final KeySet keySet, final Use use, final NegotiationStatus negotiationStatus, final boolean negotiationValue, final BooleanResultFunction resultFunction, final Boolean defaultValue) {
          super(keySet, NegotiationType.NEGOTIATED, use, negotiationStatus, defaultValue);
          this.negotiationValue = negotiationValue;
          this.resultFunction = resultFunction;
      }
  
      @Override
      protected Object parseOffer (TargetServer target, final String values) {
          return TextParameter.parseBooleanValue(values);
      }
  
      @Override
      protected boolean inProtocolValueRange (final Object values) {
          if (values instanceof Boolean) return true;
          return false;// should never happen
      }
  
      @Override
      protected void processDeclaration (final Object values) {
          // there are no declarations, see constructor
      }
  
      @Override
      protected String processNegotiation (final Object values) {
          final boolean request = (Boolean) values;
          final boolean result = resultFunction.getResult(request, negotiationValue);
          value = result;
          return TextParameter.booleanToTextValue(result);
      }
  
      @Override
      public Boolean getBooleanValue () {
          return (Boolean) value;
      }
  
      @Override
      public Entry copy () {
          final BooleanEntry e = new BooleanEntry(keySet, use, negotiationStatus, negotiationValue, resultFunction, (Boolean) value);
          e.alreadyNegotiated = this.alreadyNegotiated;
          return e;
      }
  
  }