package org.eclipse.aether.util.filter;
   
   /*
    * Licensed to the Apache Software Foundation (ASF) under one
    * or more contributor license agreements.  See the NOTICE file
    * distributed with this work for additional information
    * regarding copyright ownership.  The ASF licenses this file
    * to you under the Apache License, Version 2.0 (the
    * "License"); you may not use this file except in compliance
   * with the License.  You may obtain a copy of the License at
   * 
   *  http://www.apache.org/licenses/LICENSE-2.0
   * 
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied.  See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  
  import java.util.Arrays;
  import java.util.Collection;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Set;
  
  import org.eclipse.aether.artifact.Artifact;
  import org.eclipse.aether.graph.Dependency;
  import org.eclipse.aether.graph.DependencyFilter;
  import org.eclipse.aether.graph.DependencyNode;
  import org.eclipse.aether.version.InvalidVersionSpecificationException;
  import org.eclipse.aether.version.Version;
  import org.eclipse.aether.version.VersionRange;
  import org.eclipse.aether.version.VersionScheme;
  
  /**
   */
  class AbstractPatternDependencyFilter
      implements DependencyFilter
  {
  
      private final Set<String> patterns = new HashSet<String>();
  
      private final VersionScheme versionScheme;
  
      /**
       * Creates a new filter using the specified patterns.
       * 
       * @param patterns The include patterns, may be {@code null} or empty to include no artifacts.
       */
      public AbstractPatternDependencyFilter( final String... patterns )
      {
          this( null, patterns );
      }
  
      /**
       * Creates a new filter using the specified patterns.
       * 
       * @param versionScheme To be used for parsing versions/version ranges. If {@code null} and pattern specifies a
       *            range no artifact will be included.
       * @param patterns The include patterns, may be {@code null} or empty to include no artifacts.
       */
      public AbstractPatternDependencyFilter( final VersionScheme versionScheme, final String... patterns )
      {
          this( versionScheme, patterns == null ? null : Arrays.asList( patterns ) );
      }
  
      /**
       * Creates a new filter using the specified patterns.
       * 
       * @param patterns The include patterns, may be {@code null} or empty to include no artifacts.
       */
      public AbstractPatternDependencyFilter( final Collection<String> patterns )
      {
          this( null, patterns );
      }
  
      /**
       * Creates a new filter using the specified patterns and {@link VersionScheme} .
       * 
       * @param versionScheme To be used for parsing versions/version ranges. If {@code null} and pattern specifies a
       *            range no artifact will be included.
       * @param patterns The include patterns, may be {@code null} or empty to include no artifacts.
       */
      public AbstractPatternDependencyFilter( final VersionScheme versionScheme, final Collection<String> patterns )
      {
          if ( patterns != null )
          {
              this.patterns.addAll( patterns );
          }
          this.versionScheme = versionScheme;
      }
  
      public boolean accept( final DependencyNode node, List<DependencyNode> parents )
      {
          final Dependency dependency = node.getDependency();
          if ( dependency == null )
          {
             return true;
         }
         return accept( dependency.getArtifact() );
     }
 
     protected boolean accept( final Artifact artifact )
     {
         for ( final String pattern : patterns )
         {
             final boolean matched = accept( artifact, pattern );
             if ( matched )
             {
                 return true;
             }
         }
         return false;
     }
 
     private boolean accept( final Artifact artifact, final String pattern )
     {
         final String[] tokens =
             new String[] { artifact.getGroupId(), artifact.getArtifactId(), artifact.getExtension(),
                 artifact.getBaseVersion() };
 
         final String[] patternTokens = pattern.split( ":" );
 
         // fail immediately if pattern tokens outnumber tokens to match
         boolean matched = ( patternTokens.length <= tokens.length );
 
         for ( int i = 0; matched && i < patternTokens.length; i++ )
         {
             matched = matches( tokens[i], patternTokens[i] );
         }
 
         return matched;
     }
 
     private boolean matches( final String token, final String pattern )
     {
         boolean matches;
 
         // support full wildcard and implied wildcard
         if ( "*".equals( pattern ) || pattern.length() == 0 )
         {
             matches = true;
         }
         // support contains wildcard
         else if ( pattern.startsWith( "*" ) && pattern.endsWith( "*" ) )
         {
             final String contains = pattern.substring( 1, pattern.length() - 1 );
 
             matches = ( token.contains( contains ) );
         }
         // support leading wildcard
         else if ( pattern.startsWith( "*" ) )
         {
             final String suffix = pattern.substring( 1, pattern.length() );
 
             matches = token.endsWith( suffix );
         }
         // support trailing wildcard
         else if ( pattern.endsWith( "*" ) )
         {
             final String prefix = pattern.substring( 0, pattern.length() - 1 );
 
             matches = token.startsWith( prefix );
         }
         // support versions range
         else if ( pattern.startsWith( "[" ) || pattern.startsWith( "(" ) )
         {
             matches = isVersionIncludedInRange( token, pattern );
         }
         // support exact match
         else
         {
             matches = token.equals( pattern );
         }
 
         return matches;
     }
 
     private boolean isVersionIncludedInRange( final String version, final String range )
     {
         if ( versionScheme == null )
         {
             return false;
         }
         else
         {
             try
             {
                 final Version parsedVersion = versionScheme.parseVersion( version );
                 final VersionRange parsedRange = versionScheme.parseVersionRange( range );
 
                 return parsedRange.containsVersion( parsedVersion );
             }
             catch ( final InvalidVersionSpecificationException e )
             {
                 return false;
             }
         }
     }
 
     @Override
     public boolean equals( final Object obj )
     {
         if ( this == obj )
         {
             return true;
         }
 
         if ( obj == null || !getClass().equals( obj.getClass() ) )
         {
             return false;
         }
 
         final AbstractPatternDependencyFilter that = (AbstractPatternDependencyFilter) obj;
 
         return this.patterns.equals( that.patterns )
             && ( this.versionScheme == null ? that.versionScheme == null
                             : this.versionScheme.equals( that.versionScheme ) );
     }
 
     @Override
     public int hashCode()
     {
         int hash = 17;
         hash = hash * 31 + patterns.hashCode();
         hash = hash * 31 + ( ( versionScheme == null ) ? 0 : versionScheme.hashCode() );
         return hash;
     }
 
 }