/*
    * This file is part of ***  M y C o R e  ***
    * See http://www.mycore.de/ for details.
    *
    * MyCoRe is free software: you can redistribute it and/or modify
    * it under the terms of the GNU General Public License as published by
    * the Free Software Foundation, either version 3 of the License, or
    * (at your option) any later version.
    *
   * MyCoRe 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 General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with MyCoRe.  If not, see <http://www.gnu.org/licenses/>.
   */
  
  package org.mycore.access.mcrimpl;
  
  import java.net.InetAddress;
  import java.net.UnknownHostException;
  import java.util.Arrays;
  import java.util.stream.IntStream;
  
  import org.mycore.common.MCRException;
  
  /**
   * A class for representing an IP Address, or a range of IP addresses
   * 
   * @author Matthias Kramm
   */
  public class MCRIPAddress {
      byte[] address;
  
      byte[] mask;
  
      public MCRIPAddress(String ip) throws UnknownHostException {
          int i = ip.indexOf('/');
  
          if (i >= 0) {
              String ipstr = ip.substring(0, i);
              String maskstr = ip.substring(i + 1);
              InetAddress address = InetAddress.getByName(ipstr);
              InetAddress mask = InetAddress.getByName(maskstr);
              init(address, mask);
          } else {
              InetAddress address = InetAddress.getByName(ip);
              init(address);
          }
      }
  
      public MCRIPAddress(InetAddress address, InetAddress mask) {
          init(address, mask);
      }
  
      public MCRIPAddress(InetAddress address) {
          init(address);
      }
  
      public void init(InetAddress address, InetAddress mask) {
          this.address = address.getAddress();
          this.mask = mask.getAddress();
      }
  
      public void init(InetAddress address) {
          this.address = address.getAddress();
          mask = new byte[this.address.length];
          Arrays.fill(mask, (byte) 255);
      }
  
      public boolean contains(MCRIPAddress other) {
          if (address.length != other.address.length) {
              return false;
          }
  
          return IntStream.range(0, address.length)
              .noneMatch(t -> (address[t] & mask[t]) != (other.address[t] & mask[t]));
      }
  
      public byte[] getAddress() {
          return address;
      }
  
      @Override
      public String toString() {
          try {
              InetAddress inetAddress = InetAddress.getByAddress(address);
              InetAddress maskAddress = InetAddress.getByAddress(mask);
              StringBuilder sb = new StringBuilder();
              sb.append(inetAddress.getHostAddress());
              sb.append('/');
              sb.append(maskAddress.getHostAddress());
              return sb.toString();
          } catch (UnknownHostException e) {
              throw new MCRException(e); //should never happen
          }
  
      }
 }