/*
    * Copyright (C) 2020-2023 Dipl.-Inform. Kai Hofmann. All rights reserved!
    */
   package de.powerstat.validation.values;
   
   
   import java.util.Arrays;
   import java.util.Locale;
   import java.util.Objects;
  import java.util.regex.Pattern;
  
  import de.powerstat.validation.interfaces.IValueObject;
  
  
  /**
   * Canonical Media-Access-Control-Adresse (MAC).
   *
   * TODO getManufacturer name
   * TODO Exists in network
   * http://standards-oui.ieee.org/oui/oui.csv
   */
  public final class MACAddress implements Comparable<MACAddress>, IValueObject
   {
    /* *
     * Cache for singletons.
     */
    // private static final Map<String, MACAddress> CACHE = new WeakHashMap<>();
  
    /**
     * Hex 00.
     */
    private static final String H00 = "00"; //$NON-NLS-1$
  
    /**
     * Hex 01.
     */
    private static final String H01 = "01"; //$NON-NLS-1$
  
    /**
     * Hex 33.
     */
    private static final String H33 = "33"; //$NON-NLS-1$
  
    /**
     * Hex 5e.
     */
    private static final String H5E = "5e"; //$NON-NLS-1$
  
    /**
     * Hex ff.
     */
    private static final String HFF = "ff"; //$NON-NLS-1$
  
    /**
     * Byte separator.
     */
    private static final String SEPARATOR = ":"; //$NON-NLS-1$
  
    /**
     * Delimiter.
     */
    private static final String DELIMITER = "-"; //$NON-NLS-1$
  
    /**
     * Delimiter constant.
     */
    private static final String DELIMITER_TXT = "delimiter"; //$NON-NLS-1$
  
    /**
     * Illegal delimiter length constant.
     */
    private static final String ILLEGAL_DELIMITER_LENGTH = "Illegal delimiter length"; //$NON-NLS-1$
  
    /**
     * Illegal delimiter character constant.
     */
    private static final String ILLEGAL_DELIMITER_CHARACTER = "Illegal delimiter character"; //$NON-NLS-1$
  
    /**
     * IP V6 regexp.
     */
    private static final Pattern IPV6_REGEXP = Pattern.compile("^[0-9a-f]{2}([:-]?[0-9a-f]{2}){5}$"); //$NON-NLS-1$
  
    /**
     * IP V6 separator regexp.
     */
    private static final Pattern IPV6_SEPARATOR_REGEXP = Pattern.compile("[:-]"); //$NON-NLS-1$
  
    /**
     * MAC address parts.
     */
    private final String[] parts;
  
  
    /**
     * Constructor.
     *
     * @param address MAC address
     * @throws NullPointerException if address is null
    * @throws IllegalArgumentException if address is not a mac address
    */
   private MACAddress(final String address)
    {
     super();
     Objects.requireNonNull(address, "address"); //$NON-NLS-1$
     if ((address.length() != 12) && (address.length() != 17))
      {
       throw new IllegalArgumentException("To short or long for a mac address"); //$NON-NLS-1$
      }
     if (!MACAddress.IPV6_REGEXP.matcher(address.toLowerCase(Locale.getDefault())).matches())
      {
       throw new IllegalArgumentException("Not a mac address"); //$NON-NLS-1$
      }
     this.parts = MACAddress.IPV6_SEPARATOR_REGEXP.split(address.toLowerCase(Locale.getDefault()));
    }
 
 
   /**
    * MACAddress factory.
    *
    * @param address MAC address
    * @return MACAddress object
    */
   public static MACAddress of(final String address)
    {
     /*
     synchronized (MACAddress.class)
      {
       MACAddress obj = MACAddress.CACHE.get(address);
       if (obj != null)
        {
         return obj;
        }
       obj = new MACAddress(address);
       MACAddress.CACHE.put(address, obj);
       return obj;
      }
     */
     return new MACAddress(address);
    }
 
 
   /**
    * Returns the value of this MACAddress as a string.
    *
    * @param delimiter Delimiter could be empty, : or -
    * @return The text value represented by this object after conversion to type string.
    */
   public String stringValue(final String delimiter)
    {
     Objects.requireNonNull(delimiter, MACAddress.DELIMITER_TXT);
     if (delimiter.length() > 1)
      {
       throw new IllegalArgumentException(MACAddress.ILLEGAL_DELIMITER_LENGTH);
      }
     if (!delimiter.isEmpty() && !MACAddress.SEPARATOR.equals(delimiter) && !MACAddress.DELIMITER.equals(delimiter))
      {
       throw new IllegalArgumentException(MACAddress.ILLEGAL_DELIMITER_CHARACTER);
      }
     return String.join(delimiter, this.parts);
    }
 
 
   /**
    * Returns the value of this MACADdress as a string with delimiter ':'.
    *
    * @return The text value represented by this object after conversion to type string.
    */
   @Override
   public String stringValue()
    {
     return stringValue(MACAddress.SEPARATOR);
    }
 
 
   /**
    * Is broadcast address.
    *
    * @return true if broadcast address, false otherwise
    */
   public boolean isBroadcast()
    {
     return MACAddress.HFF.equals(this.parts[0]) && MACAddress.HFF.equals(this.parts[1]) && MACAddress.HFF.equals(this.parts[2]) && MACAddress.HFF.equals(this.parts[3]) && MACAddress.HFF.equals(this.parts[4]) && MACAddress.HFF.equals(this.parts[5]);
    }
 
 
   /**
    * Is group.
    *
    * @return true: group, false: individual
    */
   public boolean isGroup()
    {
     return (Integer.parseInt(this.parts[0], 16) & 0x01) != 0;
    }
 
 
   /**
    * Is local.
    *
    * @return true: local, false: universal
    */
   public boolean isLocal()
    {
     return (Integer.parseInt(this.parts[0], 16) & 0x02) != 0;
    }
 
 
   /**
    * Is IP v4 multicast mac.
    *
    * @return true if mac is an ip v4 multicast address, false otherwise
    */
   public boolean isIPV4Multicast()
    {
     return MACAddress.H01.equals(this.parts[0]) && MACAddress.H00.equals(this.parts[1]) && MACAddress.H5E.equals(this.parts[2]) && ((Integer.parseInt(this.parts[3], 16) & 0x80) == 0);
    }
 
 
   /**
    * Is IP v6 multicast mac.
    *
    * @return true if mac is an ip v6 multicast address, false otherwise
    */
   public boolean isIPV6Multicast()
    {
     return MACAddress.H33.equals(this.parts[0]) && MACAddress.H33.equals(this.parts[1]);
    }
 
 
   /**
    * Is VRRP mac (Virtual Router Redundancy Protocol).
    *
    * @return true if mac is a vrrp address, false otherwise
    */
   public boolean isVRRP()
    {
     return MACAddress.H00.equals(this.parts[0]) && MACAddress.H00.equals(this.parts[1]) && MACAddress.H5E.equals(this.parts[2]) && MACAddress.H00.equals(this.parts[3]) && MACAddress.H01.equals(this.parts[4]);
    }
 
 
   /**
    * Get OUI (Organizationally Unique Identifier).
    *
    * @return OUI (MA-L) string 000000
    *
    * TODO OUI-28 (MA-M), OUI-36 (MA-S)
    */
   public String getOUI()
    {
     return String.format("%1$02X", Integer.parseInt(this.parts[0], 16) & 0xfc) + this.parts[1].toUpperCase(Locale.getDefault()) + this.parts[2].toUpperCase(Locale.getDefault()); //$NON-NLS-1$
    }
 
 
   /**
    * Calculate hash code.
    *
    * @return Hash
    * @see java.lang.Object#hashCode()
    */
   @Override
   public int hashCode()
    {
     return Arrays.hashCode(this.parts);
    }
 
 
   /**
    * Is equal with another object.
    *
    * @param obj Object
    * @return true when equal, false otherwise
    * @see java.lang.Object#equals(java.lang.Object)
    */
   @Override
   public boolean equals(final Object obj)
    {
     if (this == obj)
      {
       return true;
      }
     if (!(obj instanceof MACAddress))
      {
       return false;
      }
     final MACAddress other = (MACAddress)obj;
     return Arrays.equals(this.parts, other.parts);
    }
 
 
   /**
    * Returns the string representation of this MACAddress.
    *
    * The exact details of this representation are unspecified and subject to change, but the following may be regarded as typical:
    *
    * "MACAddress[address=00:00:00:00:00:00]"
    *
    * @return String representation of this MACAddress
    * @see java.lang.Object#toString()
    */
   @Override
   public String toString()
    {
     final var builder = new StringBuilder(21);
     builder.append("MACAddress[address=").append(String.join(MACAddress.SEPARATOR, this.parts)).append(']'); //$NON-NLS-1$
     return builder.toString();
    }
 
 
   /**
    * Compare with another object.
    *
    * @param obj Object to compare with
    * @return 0: equal; 1: greater; -1: smaller
    * @see java.lang.Comparable#compareTo(java.lang.Object)
    */
   @Override
   public int compareTo(final MACAddress obj)
    {
     Objects.requireNonNull(obj, "obj"); //$NON-NLS-1$
     return Arrays.compare(this.parts, obj.parts);
    }
 
  }