/*
    * 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.
   */
  package org.apache.commons.vfs2.filter;
  
  import java.io.Serializable;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.List;
  
  import org.apache.commons.vfs2.FileFilter;
  import org.apache.commons.vfs2.FileSelectInfo;
  import org.apache.commons.vfs2.FileSystemException;
  
  /**
   * A {@link java.io.FileFilter} providing conditional OR logic across a list of
   * file filters. This filter returns {@code true} if any filters in the list
   * return {@code true}. Otherwise, it returns {@code false}. Checking of the
   * file filter list stops when the first filter returns {@code true}.
   *
   * @author This code was originally ported from Apache Commons IO File Filter
   * @see "http://commons.apache.org/proper/commons-io/"
   * @since 2.4
   */
  public class OrFileFilter implements FileFilter, ConditionalFileFilter, Serializable {
  
      private static final long serialVersionUID = 1L;
  
      /** The list of file filters. */
      private final List<FileFilter> fileFilters;
  
      /**
       * Default constructor.
       */
      public OrFileFilter() {
          this.fileFilters = new ArrayList<>();
      }
  
      /**
       * Constructs a new file filter that ORs the result of other filters.
       *
       * @param filters array of filters, must not be null or empty
       */
      public OrFileFilter(final FileFilter... filters) {
          if (filters == null || filters.length == 0) {
              throw new IllegalArgumentException("The filters must not be null or empty");
          }
          for (final FileFilter filter : filters) {
              if (filter == null) {
                  throw new IllegalArgumentException("Null filters are not allowed");
              }
          }
          this.fileFilters = new ArrayList<>(Arrays.asList(filters));
      }
  
      /**
       * Constructs a new instance of {@code OrFileFilter} with the specified
       * filters.
       *
       * @param fileFilters the file filters for this filter, copied, null ignored
       */
      public OrFileFilter(final List<FileFilter> fileFilters) {
          if (fileFilters == null) {
              this.fileFilters = new ArrayList<>();
          } else {
              this.fileFilters = new ArrayList<>(fileFilters);
          }
      }
  
      @Override
      public boolean accept(final FileSelectInfo fileSelectInfo) throws FileSystemException {
          for (final FileFilter fileFilter : fileFilters) {
              if (fileFilter.accept(fileSelectInfo)) {
                  return true;
              }
          }
          return false;
      }
  
      @Override
      public void addFileFilter(final FileFilter fileFilter) {
          this.fileFilters.add(fileFilter);
      }
  
      @Override
     public List<FileFilter> getFileFilters() {
         return Collections.unmodifiableList(this.fileFilters);
     }
 
     @Override
     public boolean removeFileFilter(final FileFilter fileFilter) {
         return this.fileFilters.remove(fileFilter);
     }
 
     @Override
     public void setFileFilters(final List<FileFilter> fileFilters) {
         this.fileFilters.clear();
         this.fileFilters.addAll(fileFilters);
     }
 
     /**
      * Provide a String representation of this file filter.
      *
      * @return a String representation
      */
     @Override
     public String toString() {
         final StringBuilder buffer = new StringBuilder();
         buffer.append(super.toString());
         buffer.append("(");
         if (fileFilters != null) {
             for (int i = 0; i < fileFilters.size(); i++) {
                 if (i > 0) {
                     buffer.append(",");
                 }
                 final Object filter = fileFilters.get(i);
                 buffer.append(filter == null ? "null" : filter.toString());
             }
         }
         buffer.append(")");
         return buffer.toString();
     }
 
 }