/*
 * Copyright (c) 2016 Vivid Solutions.
 *
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * and Eclipse Distribution License v. 1.0 which accompanies this distribution.
 * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
 * and the Eclipse Distribution License is available at
 *
 * http://www.eclipse.org/org/documents/edl-v10.php.
 */
package org.locationtech.jts.geom;

/**
 *  Constants representing the different topological locations
 *  which can occur in a {@link Geometry}. 
 *  The constants are also used as the row and column indices 
 *  of DE-9IM {@link IntersectionMatrix}es. 
 *
 *@version 1.7
 */
public class Location {
  /**
   * The location value for the interior of a geometry.
   * Also, DE-9IM row index of the interior of the first geometry and column index of
   *  the interior of the second geometry. 
   */
  public final static int INTERIOR = 0;
  /**
   * The location value for the boundary of a geometry.
   * Also, DE-9IM row index of the boundary of the first geometry and column index of
   *  the boundary of the second geometry. 
   */
  public final static int BOUNDARY = 1;
  /**
   * The location value for the exterior of a geometry.
   * Also, DE-9IM row index of the exterior of the first geometry and column index of
   *  the exterior of the second geometry. 
   */
  public final static int EXTERIOR = 2;

  /**
   *  Used for uninitialized location values.
   */
  public final static int NONE = -1;

  /**
   *  Converts the location value to a location symbol, for example, <code>EXTERIOR => 'e'</code>
   *  .
   *
   *@param  locationValue  either EXTERIOR, BOUNDARY, INTERIOR or NONE
   *@return                either 'e', 'b', 'i' or '-'
   */
  public static char toLocationSymbol(int locationValue) {
    switch (locationValue) {
      case EXTERIOR:
        return 'e';
      case BOUNDARY:
        return 'b';
      case INTERIOR:
        return 'i';
      case NONE:
        return '-';
    }
    throw new IllegalArgumentException("Unknown location value: " + locationValue);
  }
}