/**

  * Distribution License:

  * JSword is free software; you can redistribute it and/or modify it under

  * the terms of the GNU Lesser General Public License, version 2.1 or later

  * as published by the Free Software Foundation. This program is distributed

  * in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even

  * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

  * See the GNU Lesser General Public License for more details.

  *

  * The License is available on the internet at:

  *      http://www.gnu.org/copyleft/lgpl.html

  * or by writing to:

  *      Free Software Foundation, Inc.

  *      59 Temple Place - Suite 330

  *      Boston, MA 02111-1307, USA

  *

  * © CrossWire Bible Society, 2013 - 2016

  *

  */

 package org.crosswire.jsword.book.sword.state;

 import java.io.File;

 import java.io.IOException;

 import java.io.RandomAccessFile;

 import java.net.URI;

 import org.crosswire.common.util.FileUtil;

 import org.crosswire.common.util.IOUtil;

 import org.crosswire.common.util.Reporter;

 import org.crosswire.jsword.JSMsg;

 import org.crosswire.jsword.book.BookException;

 import org.crosswire.jsword.book.BookMetaData;

 import org.crosswire.jsword.book.sword.SwordUtil;

 import org.slf4j.Logger;

 import org.slf4j.LoggerFactory;

 /**

  * Stores the random access files required for processing the passage request.

  * 

  * The caller is required to close to correctly free resources and avoid File

  * pointer leaks.

  * 

  * @see gnu.lgpl.License The GNU Lesser General Public License for details.

  * @author DM Smith

  */

 public class ZLDBackendState extends RawLDBackendState {

     /**

      * This is default package access for forcing the use of the

      * OpenFileStateManager to manage the creation. Not doing so may result in

      * new instances of OpenFileState being created for no reason, and as a

      * result, if they are released to the OpenFileStateManager by mistake this

      * would result in leakage

      * 

      * @param bookMetaData the appropriate metadata for the book

      */

      ZLDBackendState(BookMetaData bookMetaData) throws BookException {

         super(bookMetaData);

         zdxFile = null;

         zdtFile = null;

         zdxRaf = null;

         zdtRaf = null;

         lastBlockNum = -1;

         lastUncompressed = EMPTY_BYTES;

         URI path = null;

         try {

             path = SwordUtil.getExpandedDataPath(bookMetaData);

         } catch (BookException e) {

             Reporter.informUser(this, e);

             return;

         }

         try {

             zdxFile = new File(path.getPath() + EXTENSION_Z_INDEX);

             zdtFile = new File(path.getPath() + EXTENSION_Z_DATA);

             if (!zdxFile.canRead()) {

                 // TRANSLATOR: Common error condition: The file could not be read. There can be many reasons.

                 // {0} is a placeholder for the file.

                 Reporter.informUser(this, new BookException(JSMsg.gettext("Error reading {0}", zdtFile.getAbsolutePath())));

                 return;

             }

             if (!zdtFile.canRead()) {

                 // TRANSLATOR: Common error condition: The file could not be read. There can be many reasons.

                 // {0} is a placeholder for the file.

                 Reporter.informUser(this, new BookException(JSMsg.gettext("Error reading {0}", zdtFile.getAbsolutePath())));

                 return;

             }

             // Open the files

             zdxRaf = new RandomAccessFile(zdxFile, FileUtil.MODE_READ);

             zdtRaf = new RandomAccessFile(zdtFile, FileUtil.MODE_READ);

         } catch (IOException ex) {

             //failed to open the files, so close them now

             IOUtil.close(zdxRaf);

             IOUtil.close(zdtRaf);

             LOGGER.error("failed to open files", ex);

             zdxRaf = null;

             zdtRaf = null;

             return;

         }

     }

     @Override

     public void releaseResources() {

         super.releaseResources();

         lastBlockNum = -1;

         lastUncompressed = EMPTY_BYTES;

         IOUtil.close(zdxRaf);

         IOUtil.close(zdtRaf);

             zdxRaf = null;

             zdtRaf = null;

     }

     /**

      * @return the zdxRaf

      */

     public RandomAccessFile getZdxRaf() {

         return zdxRaf;

     }

     /**

      * @return the zdtRaf

      */

     public RandomAccessFile getZdtRaf() {

         return zdtRaf;

     }

     /**

      * @return the lastBlockNum

      */

     public long getLastBlockNum() {

         return lastBlockNum;

     }

     /**

      * @return the lastUncompressed

      */

     public byte[] getLastUncompressed() {

         return lastUncompressed;

     }

     /**

      * @param lastBlockNum the lastBlockNum to set

      */

     public void setLastBlockNum(long lastBlockNum) {

         this.lastBlockNum = lastBlockNum;

     }

     /**

      * @param lastUncompressed the lastUncompressed to set

      */

     public void setLastUncompressed(byte[] lastUncompressed) {

         this.lastUncompressed = lastUncompressed;

     }

     private static final byte[] EMPTY_BYTES = new byte[0];

     private static final String EXTENSION_Z_INDEX = ".zdx";

     private static final String EXTENSION_Z_DATA = ".zdt";

     /**

      * The compressed index.

      */

     private File zdxFile;

     /**

      * The compressed index random access file.

      */

     private RandomAccessFile zdxRaf;

     /**

      * The compressed text.

      */

     private  File zdtFile;

     /**

      * The compressed text random access file.

      */

     private  RandomAccessFile zdtRaf;

     /**

      * The index of the block that is cached.

      */

     private  long lastBlockNum;

     /**

      * The cache for a read of a compressed block.

      */

     private  byte[] lastUncompressed;

     /**

      * The log stream

      */

     private static final Logger LOGGER = LoggerFactory.getLogger(ZLDBackendState.class);

 }