package de.lmu.ifi.dbs.elki.utilities.optionhandling.constraints;

/*
 This file is part of ELKI:
 Environment for Developing KDD-Applications Supported by Index-Structures

 Copyright (C) 2015
 Ludwig-Maximilians-Universität München
 Lehr- und Forschungseinheit für Datenbanksysteme
 ELKI Development Team

 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU Affero General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 (at your option) any later version.

 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 Affero General Public License for more details.

 You should have received a copy of the GNU Affero General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

import de.lmu.ifi.dbs.elki.utilities.optionhandling.ParameterException;
import de.lmu.ifi.dbs.elki.utilities.optionhandling.WrongParameterValueException;
import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameters.NumberParameter;

/**
 * Represents a Less-Than-Number parameter constraint. The value of the number
 * parameter ({@link NumberParameter}) tested has to be less than the specified
 * constraint value.
 * 
 * @author Steffi Wanka
 * @since 0.2
 */
public class LessConstraint extends AbstractNumberConstraint<Number> {
  /**
   * Creates a Less-Than-Number parameter constraint.
   * <p/>
   * That is, the value of the number parameter tested has to be less than the
   * constraint value given.
   * 
   * @param constraintValue the constraint value
   */
  public LessConstraint(Number constraintValue) {
    super(constraintValue);
  }

  /**
   * Creates a Less-Than-Number parameter constraint.
   * <p/>
   * That is, the value of the number parameter tested has to be less than the
   * constraint value given.
   * 
   * @param constraintValue the constraint value
   */
  public LessConstraint(int constraintValue) {
    super(Integer.valueOf(constraintValue));
  }

  /**
   * Creates a Less-Than-Number parameter constraint.
   * <p/>
   * That is, the value of the number parameter tested has to be less than the
   * constraint value given.
   * 
   * @param constraintValue the constraint value
   */
  public LessConstraint(double constraintValue) {
    super(Double.valueOf(constraintValue));
  }

  /**
   * Checks if the number value given by the number parameter is less than the
   * constraint value. If not, a parameter exception is thrown.
   * 
   */
  @Override
  public void test(Number t) throws ParameterException {
    if (t.doubleValue() >= constraintValue.doubleValue()) {
      throw new WrongParameterValueException("Parameter Constraint Error: \n" + "The parameter value specified has to be less than " + constraintValue.toString() + ". (current value: " + t.doubleValue() + ")\n");
    }
  }

  @Override
  public String getDescription(String parameterName) {
    return parameterName + " < " + constraintValue;
  }

}
