/*
 *  DeletePDFPages
 *  A tool to manipulate PDF files by cropping each page by the specified
 *  amounts.
 *
 *  $URL: svn://svn.webarts.bc.ca/open/trunk/projects/WebARTS/ca/bc/webarts/tools/pdf/DeletePDFPages.java $
 *  Copyright (C) 2003 Tom Gutwin
 *  tgutwin@webarts.bc.ca
 *
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU General Public License
 *  as published by the Free Software Foundation; either version 2
 *  of the License, or any later version.
 *
 *  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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with the jEdit program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */

package ca.bc.webarts.tools.pdf;

import java.io.File;
import java.io.FileOutputStream;

import com.itextpdf.text.Document;
import com.itextpdf.text.PageSize;
import com.itextpdf.text.pdf.PdfContentByte;
import com.itextpdf.text.pdf.PdfImportedPage;
import com.itextpdf.text.pdf.PdfReader;
import com.itextpdf.text.pdf.PdfWriter;
import com.itextpdf.text.Rectangle;


/**
 *  A tool to manipulate PDF files by deleting each page specified by the input.
 *
 *  <br>
 *  This class can be called from the commandline or instantiated and used from
 *  other Java Objects.<br><br>
 *  <b><u>Commandline Syntax:</u></b><br>
 *  java ca.bc.webarts.tools.pdfDeletePDFPages PDFFilename page1ToDelete
 *  page2ToDelete page3ToDelete ...<br />
 *  where you can have as many integers on the commandline as pages you want
 *  to delete.<br>
 *
 * @author    tgutwin
 */
public class DeletePDFPages
{
  /** Default input filename. **/
  public static final String DEFAULT_INPUT_FILENAME = "infile.pdf";

  /**  The input filename that will be cropped and saved in output filename.
   *   DEFAULT = infile.pdf**/
  private static String inFileName_ = DEFAULT_INPUT_FILENAME;

  /**  The output filename string. DEFAULT = infile-Deleted.pdf**/
  private static String outFileName_ = "infile-Deleted.pdf";


  /**  The size of the resultant page. */
  private static Rectangle outputPageSize_ = PageSize.LETTER;//PageSize.A4;

  /**  Flags the auto execution of acro reader after the cropping.
   *   DEFAULT = false **/
  private static boolean launchAcroread_ = false;

  /**  Flags whether the gui launches on startup.
   *   DEFAULT = false **/
  private static boolean launchGui_ = false;

  /**  The path/command to run the acroreader. **/
  private static String acroCmd_ = "/home/tgutwin/bin/acro";

  /**  The usage string. **/
  private static String usage_ = "SYNTAX: DeletePDFPages PDFFilename [pageNumToDelete ...]";

  private int [] deletePages_ = null;


  /**
   * Default Constructor assumes default values for EVERYTHING.
   **/
   public DeletePDFPages()
   {

   }


  /**
   * Constructor that takes the edge crop sizes in inches.
   **/
   public DeletePDFPages(int [] deletePages)
   {
     setDeletePages(deletePages);
   }


  /**
   *  The main program for the DeletePDFPages class
   *
   * @param  args  The command line arguments
   */
  public static void main(String[] args)
  {
    DeletePDFPages instance = new DeletePDFPages();
    boolean validParms = instance.parseCmdlineParms(args);


    /*
     *  Parms are now parsed.... start the transform/crop
     */
    if (validParms)
    {
      if (launchGui_)
      {
        // launch gui for crop info
      }
      else
        // just do the crop
        instance.doDelete();
    }
    else
    {
      // nothing for now.
    }
  }


  /**
   * Parses the input commandline parameters and assigns the various class
   * variables.
   *
   * @return success or failure
   **/
  public boolean parseCmdlineParms(String [] args)
  {
    boolean retVal = false;

    if (args.length > 1)
    {
      setInFileName(args[0]);
      setOutFileName(null);
      deletePages_ = new int[args.length -1];
      for (int i = 0; i < args.length -1; i++)
        deletePages_[i] = Integer.parseInt(args[i+1]) -1;
      retVal = true;
    }
    else
      System.out.println(usage_);

    return retVal;
  }



  /**
   * Executes the deleting as specified by the class parms.
   *
   * @return success or failure
   **/
  public boolean doDelete()
  {
    boolean retVal = true;

    try
    {
      // we create a reader for a certain document
      System.out.println("Reading: " + inFileName_);
      PdfReader reader = new PdfReader(inFileName_);

      // step 1: creation of a document-object
      // we retrieve the total number of pages
      int numPages = reader.getNumberOfPages();
      Document document =
          new Document(outputPageSize_, 0, 0, 0, 0);// Margins: left, right,top, bottom

      // step 2: we create a writer that listens to the document
      System.out.println("Writing: " + outFileName_);
      FileOutputStream outFileStream = new FileOutputStream(outFileName_);
      PdfWriter writer = PdfWriter.getInstance(document, outFileStream);

      // step 3: we open the document
      document.open();

      // step 4: calculate the new scaling / layout postion
      PdfContentByte cb = writer.getDirectContent();
      System.out.println("There are " + numPages +
          " pages in the document.");
       System.out.println("Deleting " + deletePages_.length +
          " pages.");
      PdfImportedPage leftPage;
      int currentPage = 0;


      /*
       *  step 5: Start Copying the pages to the new Doc (in 2Up format)
       */
      /*
       *  ******* ******************************************************
       */
      System.out.print(" Adding pages: ");
      while (currentPage < numPages)
      {
        if (!pageToDelete(currentPage))
        {
          System.out.print((currentPage+1)+" " );
          document.newPage();
          leftPage = writer.getImportedPage(reader, ++currentPage);
          cb.addTemplate(leftPage,0.0f,0.0f); //, a, b, c, d, -(leftCropBorder_* 72.0f),
                                    //           -(bottomCropBorder_* 72.0f));
        }
        else
          currentPage++;
      }
      System.out.println(" ." );

      // step 6: we close the document
      document.close();
    }
    catch (Exception de)
    {
      de.printStackTrace();
      retVal = false;
    }

    return retVal;
  }


  private boolean pageToDelete(int num)
  {
    boolean retVal = false;
    for (int i=0; !retVal && i < deletePages_.length;i++)
      if (deletePages_[i] == num)
        retVal = true;
    return retVal;
  }


  /**
   * Setter.
   **/
  public void setDeletePages(int [] parm)
  {
    this.deletePages_ = parm;
  }


  /**
   * Getter.
   **/
  public int [] getDeletePages()
  {
    return deletePages_;
  }


  /**
   * Setter for input filename. IT MUST END WITH A ".pdf".
   **/
  public void setInFileName(String inFileName)
  {
    if (inFileName == null ||
        inFileName.equals("") ||
        !inFileName.endsWith(".pdf"))
      this.inFileName_ = DEFAULT_INPUT_FILENAME;
    else
      this.inFileName_ = inFileName;
  }


  /**
   * Getter.
   **/
  public String getInFileName()
  {
    return inFileName_;
  }


  /**
   * Setter.
   **/
  public void setOutFileName()
  {
    setOutFileName(null);
  }


  /**
   * Setter.
   **/
  public void setOutFileName(String outFileName)
  {
    if (outFileName == null || outFileName.equals(""))
      this.outFileName_ = this.inFileName_.substring(
                              0, this.inFileName_.length() - 4) + "-Deleted.pdf";
    else
      this.outFileName_ = outFileName;
  }


  /**
   * Getter.
   **/
  public String getOutFileName()
  {
    return outFileName_;
  }


}