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.Collections;
  import java.util.HashSet;
  
  import org.eclipse.aether.graph.DependencyFilter;
  import org.eclipse.aether.util.artifact.JavaScopes;
  
  /**
   * A utility class assisting in the creation of dependency node filters.
   */
  public final class DependencyFilterUtils
  {
  
      private DependencyFilterUtils()
      {
          // hide constructor
      }
  
      /**
       * Creates a new filter that negates the specified filter.
       * 
       * @param filter The filter to negate, must not be {@code null}.
       * @return The new filter, never {@code null}.
       */
      public static DependencyFilter notFilter( DependencyFilter filter )
      {
          return new NotDependencyFilter( filter );
      }
  
      /**
       * Creates a new filter that combines the specified filters using a logical {@code AND}. If no filters are
       * specified, the resulting filter accepts everything.
       * 
       * @param filters The filters to combine, may be {@code null}.
       * @return The new filter, never {@code null}.
       */
      public static DependencyFilter andFilter( DependencyFilter... filters )
      {
          if ( filters != null && filters.length == 1 )
          {
              return filters[0];
          }
          else
          {
              return new AndDependencyFilter( filters );
          }
      }
  
      /**
       * Creates a new filter that combines the specified filters using a logical {@code AND}. If no filters are
       * specified, the resulting filter accepts everything.
       * 
       * @param filters The filters to combine, may be {@code null}.
       * @return The new filter, never {@code null}.
       */
      public static DependencyFilter andFilter( Collection<DependencyFilter> filters )
      {
          if ( filters != null && filters.size() == 1 )
          {
              return filters.iterator().next();
          }
          else
          {
              return new AndDependencyFilter( filters );
          }
      }
  
      /**
       * Creates a new filter that combines the specified filters using a logical {@code OR}. If no filters are specified,
       * the resulting filter accepts nothing.
       * 
       * @param filters The filters to combine, may be {@code null}.
       * @return The new filter, never {@code null}.
       */
      public static DependencyFilter orFilter( DependencyFilter... filters )
      {
          if ( filters != null && filters.length == 1 )
         {
             return filters[0];
         }
         else
         {
             return new OrDependencyFilter( filters );
         }
     }
 
     /**
      * Creates a new filter that combines the specified filters using a logical {@code OR}. If no filters are specified,
      * the resulting filter accepts nothing.
      * 
      * @param filters The filters to combine, may be {@code null}.
      * @return The new filter, never {@code null}.
      */
     public static DependencyFilter orFilter( Collection<DependencyFilter> filters )
     {
         if ( filters != null && filters.size() == 1 )
         {
             return filters.iterator().next();
         }
         else
         {
             return new OrDependencyFilter( filters );
         }
     }
 
     /**
      * Creates a new filter that selects dependencies whose scope matches one or more of the specified classpath types.
      * A classpath type is a set of scopes separated by either {@code ','} or {@code '+'}.
      * 
      * @param classpathTypes The classpath types, may be {@code null} or empty to match no dependency.
      * @return The new filter, never {@code null}.
      * @see JavaScopes
      */
     public static DependencyFilter classpathFilter( String... classpathTypes )
     {
         return classpathFilter( ( classpathTypes != null ) ? Arrays.asList( classpathTypes ) : null );
     }
 
     /**
      * Creates a new filter that selects dependencies whose scope matches one or more of the specified classpath types.
      * A classpath type is a set of scopes separated by either {@code ','} or {@code '+'}.
      * 
      * @param classpathTypes The classpath types, may be {@code null} or empty to match no dependency.
      * @return The new filter, never {@code null}.
      * @see JavaScopes
      */
     public static DependencyFilter classpathFilter( Collection<String> classpathTypes )
     {
         Collection<String> types = new HashSet<>();
 
         if ( classpathTypes != null )
         {
             for ( String classpathType : classpathTypes )
             {
                 String[] tokens = classpathType.split( "[+,]" );
                 for ( String token : tokens )
                 {
                     token = token.trim();
                     if ( token.length() > 0 )
                     {
                         types.add( token );
                     }
                 }
             }
         }
 
         Collection<String> included = new HashSet<>();
         for ( String type : types )
         {
             if ( JavaScopes.COMPILE.equals( type ) )
             {
                 Collections.addAll( included, JavaScopes.COMPILE, JavaScopes.PROVIDED, JavaScopes.SYSTEM );
             }
             else if ( JavaScopes.RUNTIME.equals( type ) )
             {
                 Collections.addAll( included, JavaScopes.COMPILE, JavaScopes.RUNTIME );
             }
             else if ( JavaScopes.TEST.equals( type ) )
             {
                 Collections.addAll( included, JavaScopes.COMPILE, JavaScopes.PROVIDED, JavaScopes.SYSTEM,
                                     JavaScopes.RUNTIME, JavaScopes.TEST );
             }
             else
             {
                 included.add( type );
             }
         }
 
         Collection<String> excluded = new HashSet<>();
         Collections.addAll( excluded, JavaScopes.COMPILE, JavaScopes.PROVIDED, JavaScopes.SYSTEM, JavaScopes.RUNTIME,
                             JavaScopes.TEST );
         excluded.removeAll( included );
 
         return new ScopeDependencyFilter( null, excluded );
     }
 
 }