//
   //  ========================================================================
   //  Copyright (c) 1995-2016 Mort Bay Consulting Pty. Ltd.
   //  ------------------------------------------------------------------------
   //  All rights reserved. This program and the accompanying materials
   //  are made available under the terms of the Eclipse Public License v1.0
   //  and Apache License v2.0 which accompanies this distribution.
   //
   //      The Eclipse Public License is available at
  //      http://www.eclipse.org/legal/epl-v10.html
  //
  //      The Apache License v2.0 is available at
  //      http://www.opensource.org/licenses/apache2.0.php
  //
  //  You may elect to redistribute this code under either of these licenses.
  //  ========================================================================
  //
  
  package org.eclipse.jetty.util;
  
  import java.util.BitSet;
  import java.util.HashMap;
  import java.util.Map;
  import java.util.StringTokenizer;
  
  
  /* ------------------------------------------------------------ */
  /**
   * Internet address map to object
   * <p>
   * Internet addresses may be specified as absolute address or as a combination of 
   * four octet wildcard specifications (a.b.c.d) that are defined as follows.
   * </p>
   * <pre>
   *     nnn  - an absolute value (0-255)
   * mmm-nnn  - an inclusive range of absolute values, 
   *            with following shorthand notations:
   *              nnn- =&gt; nnn-255
   *             -nnn  =&gt; 0-nnn
   *             -     =&gt; 0-255
   *          a,b,...  - a list of wildcard specifications
   * </pre>
   * @param <TYPE> the Map Entry value type
   */
  @SuppressWarnings("serial")
  public class IPAddressMap<TYPE> extends HashMap<String, TYPE>
  {
      private final HashMap<String,IPAddrPattern> _patterns = new HashMap<String,IPAddrPattern>();
  
      /* --------------------------------------------------------------- */
      /** Construct empty IPAddressMap.
       */
      public IPAddressMap()
      {
          super(11);
      }
     
      /* --------------------------------------------------------------- */
      /** Construct empty IPAddressMap.
       * 
       * @param capacity initial capacity
       */
      public IPAddressMap(int capacity)
      {
          super (capacity);
      }
  
      /* ------------------------------------------------------------ */
      /**
       * Insert a new internet address into map
       * 
       * @see java.util.HashMap#put(java.lang.Object, java.lang.Object)
       */
      @Override
      public TYPE put(String addrSpec, TYPE object)
          throws IllegalArgumentException
      {
          if (addrSpec == null || addrSpec.trim().length() == 0)
              throw new IllegalArgumentException("Invalid IP address pattern: "+addrSpec);
          
          String spec = addrSpec.trim();
          if (_patterns.get(spec) == null)
              _patterns.put(spec,new IPAddrPattern(spec));
          
          return super.put(spec, object);
      }
      
      /* ------------------------------------------------------------ */
      /**
       * Retrieve the object mapped to the specified internet address literal
       * 
       * @see java.util.HashMap#get(java.lang.Object)
       */
      @Override
      public TYPE get(Object key)
      {
          return super.get(key);
      }
      
     /* ------------------------------------------------------------ */
     /**
      * Retrieve the first object that is associated with the specified 
      * internet address by taking into account the wildcard specifications.
      * 
      * @param addr internet address
      * @return associated object
      */
     public TYPE match(String addr)
     {
         Map.Entry<String, TYPE> entry = getMatch(addr);
         return entry==null ? null : entry.getValue();
     }
     
     /* ------------------------------------------------------------ */
     /**
      * Retrieve the first map entry that is associated with the specified 
      * internet address by taking into account the wildcard specifications.
      * 
      * @param addr internet address
      * @return map entry associated
      */
     public Map.Entry<String, TYPE> getMatch(String addr)
     {
         if (addr != null)
         {
             for(Map.Entry<String, TYPE> entry: super.entrySet())
             {
                 if (_patterns.get(entry.getKey()).match(addr))
                 {
                     return entry;
                 }
             }
         }
         return null;
     }
     
     /* ------------------------------------------------------------ */
     /**
      * Retrieve a lazy list of map entries associated with specified
      * internet address by taking into account the wildcard specifications.
      * 
      * @param addr  internet address
      * @return lazy list of map entries
      */
     public Object getLazyMatches(String addr)
     {
         if (addr == null)
             return LazyList.getList(super.entrySet());
         
         Object entries = null;
         for(Map.Entry<String, TYPE> entry: super.entrySet())
         {
             if (_patterns.get(entry.getKey()).match(addr))
             {
                 entries = LazyList.add(entries,entry);
             }
         }
         return entries;        
     }
     
     /* ------------------------------------------------------------ */
     /**
      * IPAddrPattern
      * 
      * Represents internet address wildcard. 
      * Matches the wildcard to provided internet address.
      */
     private static class IPAddrPattern
     {
         private final OctetPattern[] _octets = new OctetPattern[4];
         /* ------------------------------------------------------------ */
         /**
          * Create new IPAddrPattern
          * 
          * @param value internet address wildcard specification
          * @throws IllegalArgumentException if wildcard specification is invalid
          */
         public IPAddrPattern(String value)
             throws IllegalArgumentException
         {
             if (value == null || value.trim().length() == 0)
                 throw new IllegalArgumentException("Invalid IP address pattern: "+value);
                 
             try
             {
                 StringTokenizer parts = new StringTokenizer(value, ".");
                 
                 String part;
                 for (int idx=0; idx<4; idx++)
                 {
                     part = parts.hasMoreTokens() ? parts.nextToken().trim() : "0-255";
                     
                     int len = part.length();
                     if (len == 0 && parts.hasMoreTokens())
                         throw new IllegalArgumentException("Invalid IP address pattern: "+value);
                     
                     _octets[idx] = new OctetPattern(len==0 ? "0-255" : part);
                 }
             }
             catch (IllegalArgumentException ex)
             {
                 throw new IllegalArgumentException("Invalid IP address pattern: "+value, ex);
             }
         }
         
         /* ------------------------------------------------------------ */
         /**
          * Match the specified internet address against the wildcard
          * 
          * @param value internet address
          * @return true if specified internet address matches wildcard specification
          * 
          * @throws IllegalArgumentException if specified internet address is invalid
          */
         public boolean match(String value)
             throws IllegalArgumentException
         {
             if (value == null || value.trim().length() == 0)
                 throw new IllegalArgumentException("Invalid IP address: "+value);
             
             try
             {
                 StringTokenizer parts = new StringTokenizer(value, ".");
                 
                 boolean result = true;
                 for (int idx=0; idx<4; idx++)
                 {
                     if (!parts.hasMoreTokens())
                         throw new IllegalArgumentException("Invalid IP address: "+value);
                         
                     if (!(result &= _octets[idx].match(parts.nextToken())))
                         break;
                 }
                 return result;
             }
             catch (IllegalArgumentException ex)
             {
                 throw new IllegalArgumentException("Invalid IP address: "+value, ex);
             }
         }
     }
         
     /* ------------------------------------------------------------ */
     /**
      * OctetPattern
      * 
      * Represents a single octet wildcard.
      * Matches the wildcard to the specified octet value.
      */
     private static class OctetPattern extends BitSet
     {
         private final BitSet _mask = new BitSet(256);
         
         /* ------------------------------------------------------------ */
         /**
          * Create new OctetPattern
          * 
          * @param octetSpec octet wildcard specification
          * @throws IllegalArgumentException if wildcard specification is invalid
          */
         public OctetPattern(String octetSpec)
             throws IllegalArgumentException
         {
             try
             {
                 if (octetSpec != null)
                 {
                     String spec = octetSpec.trim();
                     if(spec.length() == 0)
                     {
                         _mask.set(0,255);
                     }
                     else
                     {
                         StringTokenizer parts = new StringTokenizer(spec,",");
                         while (parts.hasMoreTokens())
                         {
                             String part = parts.nextToken().trim();
                             if (part.length() > 0)
                             {
                                 if (part.indexOf('-') < 0)
                                 {
                                     Integer value = Integer.valueOf(part);
                                     _mask.set(value);
                                 }
                                 else
                                 {
                                     int low = 0, high = 255;
                                     
                                     String[] bounds = part.split("-",-2);
                                     if (bounds.length != 2)
                                     {
                                         throw new IllegalArgumentException("Invalid octet spec: "+octetSpec);
                                     }
                                     
                                     if (bounds[0].length() > 0)
                                     {
                                         low = Integer.parseInt(bounds[0]);
                                     }
                                     if (bounds[1].length() > 0)
                                     {
                                         high = Integer.parseInt(bounds[1]);
                                     }
                                     
                                     if (low > high)
                                     {
                                         throw new IllegalArgumentException("Invalid octet spec: "+octetSpec);
                                     }
                                     
                                     _mask.set(low, high+1);
                                 }
                             }
                         }
                     }
                 }
             }
             catch (NumberFormatException ex)
             {
                 throw new IllegalArgumentException("Invalid octet spec: "+octetSpec, ex);
             }
         }
         
         /* ------------------------------------------------------------ */
         /**
          * Match specified octet value against the wildcard
          * 
          * @param value octet value
          * @return true if specified octet value matches the wildcard
          * @throws IllegalArgumentException if specified octet value is invalid
          */
         public boolean match(String value)
             throws IllegalArgumentException
         {
             if (value == null || value.trim().length() == 0)
                 throw new IllegalArgumentException("Invalid octet: "+value);
 
             try
             {
                 int number = Integer.parseInt(value);
                 return match(number);
             }
             catch (NumberFormatException ex)
             {
                 throw new IllegalArgumentException("Invalid octet: "+value);
             }
         }
         
         /* ------------------------------------------------------------ */
         /**
          * Match specified octet value against the wildcard
          * 
          * @param number octet value
          * @return true if specified octet value matches the wildcard
          * @throws IllegalArgumentException if specified octet value is invalid
          */
         public boolean match(int number)
             throws IllegalArgumentException
         {
             if (number < 0 || number > 255)
                 throw new IllegalArgumentException("Invalid octet: "+number);
             
             return _mask.get(number);
         }
     }   
 }