/*
    * 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.logging.log4j.core.appender.rolling.action;
  
  import java.nio.file.FileSystem;
  import java.nio.file.FileSystems;
  import java.nio.file.Path;
  import java.nio.file.PathMatcher;
  import java.nio.file.attribute.BasicFileAttributes;
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.List;
  import java.util.regex.Pattern;
  
  import org.apache.logging.log4j.Logger;
  import org.apache.logging.log4j.core.config.plugins.Plugin;
  import org.apache.logging.log4j.core.config.plugins.PluginAttribute;
  import org.apache.logging.log4j.core.config.plugins.PluginElement;
  import org.apache.logging.log4j.core.config.plugins.PluginFactory;
  import org.apache.logging.log4j.status.StatusLogger;
  
  /**
   * PathCondition that accepts files for deletion if their relative path matches either a glob pattern or a regular
   * expression. If both a regular expression and a glob pattern are specified the glob pattern is used and the regular
   * expression is ignored.
   * <p>
   * The regular expression is a pattern as defined by the {@link Pattern} class. A glob is a simplified pattern
   * expression described in {@link FileSystem#getPathMatcher(String)}.
   */
  @Plugin(name = "IfFileName", category = "Core", printObject = true)
  public final class IfFileName implements PathCondition {
      private static final Logger LOGGER = StatusLogger.getLogger();
      private final PathMatcher pathMatcher;
      private final String syntaxAndPattern;
      private final PathCondition[] nestedConditions;
  
      /**
       * Constructs a FileNameFilter filter. If both a regular expression and a glob pattern are specified the glob
       * pattern is used and the regular expression is ignored.
       * 
       * @param glob the baseDir-relative path pattern of the files to delete (may contain '*' and '?' wildcarts)
       * @param regex the regular expression that matches the baseDir-relative path of the file(s) to delete
       * @param nestedConditions nested conditions to evaluate if this condition accepts a path
       */
      private IfFileName(final String glob, final String regex, final PathCondition[] nestedConditions) {
          if (regex == null && glob == null) {
              throw new IllegalArgumentException("Specify either a path glob or a regular expression. "
                      + "Both cannot be null.");
          }
          this.syntaxAndPattern = createSyntaxAndPatternString(glob, regex);
          this.pathMatcher = FileSystems.getDefault().getPathMatcher(syntaxAndPattern);
          this.nestedConditions = nestedConditions == null ? new PathCondition[0] : Arrays.copyOf(nestedConditions,
                  nestedConditions.length);
      }
  
      static String createSyntaxAndPatternString(final String glob, final String regex) {
          if (glob != null) {
              return glob.startsWith("glob:") ? glob : "glob:" + glob;
          }
          return regex.startsWith("regex:") ? regex : "regex:" + regex;
      }
  
      /**
       * Returns the baseDir-relative path pattern of the files to delete. The returned string takes the form
       * {@code syntax:pattern} where syntax is one of "glob" or "regex" and the pattern is either a {@linkplain Pattern
       * regular expression} or a simplified pattern expression described under "glob" in
       * {@link FileSystem#getPathMatcher(String)}.
       * 
       * @return relative path of the file(s) to delete (may contain regular expression or wildcarts)
       */
      public String getSyntaxAndPattern() {
          return syntaxAndPattern;
      }
  
      public List<PathCondition> getNestedConditions() {
          return Collections.unmodifiableList(Arrays.asList(nestedConditions));
      }
  
      /*
       * (non-Javadoc)
       * 
       * @see org.apache.logging.log4j.core.appender.rolling.action.PathCondition#accept(java.nio.file.Path,
       * java.nio.file.Path, java.nio.file.attribute.BasicFileAttributes)
       */
      @Override
     public boolean accept(final Path basePath, final Path relativePath, final BasicFileAttributes attrs) {
         final boolean result = pathMatcher.matches(relativePath);
 
         final String match = result ? "matches" : "does not match";
         final String accept = result ? "ACCEPTED" : "REJECTED";
         LOGGER.trace("IfFileName {}: '{}' {} relative path '{}'", accept, syntaxAndPattern, match, relativePath);
         if (result) {
             return IfAll.accept(nestedConditions, basePath, relativePath, attrs);
         }
         return result;
     }
 
     /*
      * (non-Javadoc)
      * 
      * @see org.apache.logging.log4j.core.appender.rolling.action.PathCondition#beforeFileTreeWalk()
      */
     @Override
     public void beforeFileTreeWalk() {
         IfAll.beforeFileTreeWalk(nestedConditions);
     }
 
     /**
      * Creates a IfFileName condition that returns true if either the specified
      * {@linkplain FileSystem#getPathMatcher(String) glob pattern} or the regular expression matches the relative path.
      * If both a regular expression and a glob pattern are specified the glob pattern is used and the regular expression
      * is ignored.
      * 
      * @param glob the baseDir-relative path pattern of the files to delete (may contain '*' and '?' wildcarts)
      * @param regex the regular expression that matches the baseDir-relative path of the file(s) to delete
      * @param nestedConditions nested conditions to evaluate if this condition accepts a path
      * @return A IfFileName condition.
      * @see FileSystem#getPathMatcher(String)
      */
     @PluginFactory
     public static IfFileName createNameCondition( //
             // @formatter:off
             @PluginAttribute("glob") final String glob, //
             @PluginAttribute("regex") final String regex, //
             @PluginElement("PathConditions") final PathCondition... nestedConditions) {
             // @formatter:on
         return new IfFileName(glob, regex, nestedConditions);
     }
 
     @Override
     public String toString() {
         final String nested = nestedConditions.length == 0 ? "" : " AND " + Arrays.toString(nestedConditions);
         return "IfFileName(" + syntaxAndPattern + nested + ")";
     }
 }