/*
    * 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.imaging.bytesource;
  
  import java.io.File;
  import java.io.IOException;
  import java.io.InputStream;
  import java.nio.file.Path;
  import java.util.Objects;
  
  import org.apache.commons.imaging.common.BinaryFunctions;
  import org.apache.commons.io.IOUtils;
  import org.apache.commons.io.build.AbstractOrigin;
  import org.apache.commons.io.build.AbstractOrigin.ByteArrayOrigin;
  import org.apache.commons.io.build.AbstractOrigin.FileOrigin;
  import org.apache.commons.io.build.AbstractOrigin.PathOrigin;
  
  public class ByteSource {
  
      public static ByteSource array(final byte[] array) {
          return new ByteSource(new ByteArrayOrigin(array), null);
      }
  
      public static ByteSource array(final byte[] array, final String name) {
          return new ByteSource(new ByteArrayOrigin(array), name);
      }
  
      public static ByteSource file(final File file) {
          return new ByteSource(new FileOrigin(file), file.getName());
      }
  
      public static final InputStream getInputStream(final ByteSource byteSource, final long skip) throws IOException {
          InputStream is = null;
          boolean succeeded = false;
          try {
              is = byteSource.getInputStream();
              BinaryFunctions.skipBytes(is, skip);
              succeeded = true;
          } finally {
              if (!succeeded) {
                  IOUtils.close(is);
              }
          }
          return is;
      }
  
      public static ByteSource inputStream(final InputStream is, final String name) throws IOException {
          return new InputStreamByteSource(is, name);
      }
  
      public static ByteSource path(final Path file) {
          return new ByteSource(new PathOrigin(file), Objects.toString(file.getFileName(), null));
      }
  
      private final String fileName;
      private final AbstractOrigin<?, ?> origin;
  
      ByteSource(final AbstractOrigin<?, ?> origin, final String fileName) {
          this.origin = Objects.requireNonNull(origin, "origin");
          this.fileName = fileName; // may be null
      }
  
      public byte[] getByteArray(final long position, final int length) throws IOException {
          return origin.getByteArray(position, length);
      }
  
      public final String getFileName() {
          return fileName;
      }
  
      public InputStream getInputStream() throws IOException {
          return origin.getInputStream();
      }
  
      /**
       * This operation can be VERY expensive; for InputStream byte sources, the entire stream must be drained to determine its length.
       *
       * @return the byte source length
       * @throws IOException if it fails to read the byte source data
       */
      public long size() throws IOException {
          return origin.size();
      }
  
      @Override
     public String toString() {
         return getClass().getSimpleName() + "[" + getFileName() + "]";
     }
 
 }