/*
 * 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.tsfile.external.commons.io.filefilter;

import org.apache.tsfile.external.commons.io.file.PathFilter;
import org.apache.tsfile.external.commons.io.file.PathVisitor;
import org.apache.tsfile.external.commons.io.function.IOSupplier;

import java.io.File;
import java.io.FileFilter;
import java.io.FilenameFilter;
import java.io.IOException;
import java.nio.file.FileVisitResult;
import java.nio.file.Path;
import java.nio.file.attribute.BasicFileAttributes;
import java.util.List;
import java.util.Objects;

/**
 * Abstracts the implementation of the {@link FileFilter} (IO), {@link FilenameFilter} (IO), {@link
 * PathFilter} (NIO) interfaces via our own {@link IOFileFilter} interface.
 *
 * <p>Note that a subclass MUST override one of the {@code accept} methods, otherwise that subclass
 * will infinitely loop.
 *
 * @since 1.0
 */
public abstract class AbstractFileFilter implements IOFileFilter, PathVisitor {

  static FileVisitResult toDefaultFileVisitResult(final boolean accept) {
    return accept ? FileVisitResult.CONTINUE : FileVisitResult.TERMINATE;
  }

  /** What to do when this filter accepts. */
  private final FileVisitResult onAccept;

  /** What to do when this filter rejects. */
  private final FileVisitResult onReject;

  /** Constructs a new instance. */
  public AbstractFileFilter() {
    this(FileVisitResult.CONTINUE, FileVisitResult.TERMINATE);
  }

  /**
   * Constructs a new instance.
   *
   * @param onAccept What to do on acceptance.
   * @param onReject What to do on rejection.
   * @since 2.12.0.
   */
  protected AbstractFileFilter(final FileVisitResult onAccept, final FileVisitResult onReject) {
    this.onAccept = onAccept;
    this.onReject = onReject;
  }

  /**
   * Checks to see if the File should be accepted by this filter.
   *
   * @param file the File to check
   * @return true if this file matches the test
   */
  @Override
  public boolean accept(final File file) {
    Objects.requireNonNull(file, "file");
    return accept(file.getParentFile(), file.getName());
  }

  /**
   * Checks to see if the File should be accepted by this filter.
   *
   * @param dir the directory File to check
   * @param name the file name within the directory to check
   * @return true if this file matches the test
   */
  @Override
  public boolean accept(final File dir, final String name) {
    Objects.requireNonNull(name, "name");
    return accept(new File(dir, name));
  }

  void append(final List<?> list, final StringBuilder buffer) {
    for (int i = 0; i < list.size(); i++) {
      if (i > 0) {
        buffer.append(",");
      }
      buffer.append(list.get(i));
    }
  }

  void append(final Object[] array, final StringBuilder buffer) {
    for (int i = 0; i < array.length; i++) {
      if (i > 0) {
        buffer.append(",");
      }
      buffer.append(array[i]);
    }
  }

  FileVisitResult get(final IOSupplier<FileVisitResult> supplier) {
    try {
      return supplier.get();
    } catch (final IOException e) {
      return handle(e);
    }
  }

  /**
   * Handles exceptions caught while accepting.
   *
   * @param t the caught Throwable.
   * @return the given Throwable.
   * @since 2.9.0
   */
  protected FileVisitResult handle(final Throwable t) {
    return FileVisitResult.TERMINATE;
  }

  @Override
  public FileVisitResult postVisitDirectory(final Path dir, final IOException exc)
      throws IOException {
    return FileVisitResult.CONTINUE;
  }

  @Override
  public FileVisitResult preVisitDirectory(final Path dir, final BasicFileAttributes attributes)
      throws IOException {
    return accept(dir, attributes);
  }

  /**
   * Converts a boolean into a FileVisitResult.
   *
   * @param accept accepted or rejected.
   * @return a FileVisitResult.
   */
  FileVisitResult toFileVisitResult(final boolean accept) {
    return accept ? onAccept : onReject;
  }

  /**
   * Provides a String representation of this file filter.
   *
   * @return a String representation
   */
  @Override
  public String toString() {
    return getClass().getSimpleName();
  }

  @Override
  public FileVisitResult visitFile(final Path file, final BasicFileAttributes attributes)
      throws IOException {
    return accept(file, attributes);
  }

  @Override
  public FileVisitResult visitFileFailed(final Path file, final IOException exc)
      throws IOException {
    return FileVisitResult.CONTINUE;
  }
}
