/**
 * <copyright> Copyright 2006 by Know-Center, Graz, Austria </copyright>
 * PDF-AS has been contracted by the E-Government Innovation Center EGIZ, a
 * joint initiative of the Federal Chancellery Austria and Graz University of
 * Technology.
 *
 * Licensed under the EUPL, Version 1.1 or - as soon they will be approved by
 * the European Commission - subsequent versions of the EUPL (the "Licence");
 * You may not use this work except in compliance with the Licence.
 * You may obtain a copy of the Licence at:
 * http://www.osor.eu/eupl/
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the Licence is distributed on an "AS IS" basis,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the Licence for the specific language governing permissions and
 * limitations under the Licence.
 *
 * This product combines work with different licenses. See the "NOTICE" text
 * file for details on the various modules and licenses.
 * The "NOTICE" text file is part of the distribution. Any derivative works
 * that you distribute must include a readable copy of the "NOTICE" text file.
 */
package at.gv.egiz.pdfas.io;

import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;

import at.gv.egiz.pdfas.api.io.DataSource;
import at.gv.egiz.pdfas.api.io.FileBased;
import at.gv.egiz.pdfas.impl.input.helper.DataSourceHelper;

/**
 * A FileBased DataSource implementation.
 * 
 * @author wprinz
 */
public class FileBasedDataSource implements DataSource, FileBased
{
  protected File file = null;

  protected String mimeType = null;

  protected String characterEncoding = null;

  protected byte[] cache = null;

  /**
   * @param file
   * @param mimeType
   * @throws IOException
   */
  public FileBasedDataSource(File file, String mimeType) throws IOException
  {
    this(file, mimeType, null);
  }

  /**
   * @param file
   * @param mimeType
   * @param characterEncoding
   * @throws IOException
   */
  public FileBasedDataSource(File file, String mimeType, String characterEncoding) throws IOException
  {
    if (file == null)
    {
      throw new IllegalArgumentException("The file must not be null.");
    }
    if (mimeType == null)
    {
      throw new IllegalArgumentException("The mimeType must not be null.");
    }
    if (!file.exists())
    {
      throw new FileNotFoundException("The file '" + file + "' does not exist.");
    }
    if (!file.canRead())
    {
      throw new IOException("The file '" + file + "' cannot be read.");
    }

    this.file = file;
    this.mimeType = mimeType;
    this.characterEncoding = characterEncoding;
    this.cache = DataSourceHelper.convertInputStreamToByteArrayIOEx(new FileInputStream(this.file));
  }

  /**
   * @see at.gv.egiz.pdfas.api.io.DataSource#createInputStream()
   */
  public InputStream createInputStream()
  {
    return new ByteArrayInputStream(this.cache);
  }

  /**
   * @see at.gv.egiz.pdfas.api.io.DataSource#getAsByteArray()
   */
  public byte[] getAsByteArray()
  {
    return this.cache;
  }

  /**
   * @see at.gv.egiz.pdfas.api.io.DataSource#getLength()
   */
  public int getLength()
  {
    return this.cache.length;
  }

  /**
   * @see at.gv.egiz.pdfas.api.io.DataSource#getMimeType()
   */
  public String getMimeType()
  {
    return this.mimeType;
  }

  /**
   * @see at.gv.egiz.pdfas.api.io.DataSource#getCharacterEncoding()
   */
  public String getCharacterEncoding()
  {
    return this.characterEncoding;
  }

  /**
   * @see at.gv.egiz.pdfas.api.io.FileBased#getFile()
   */
  public File getFile()
  {
    return this.file;
  }

}