#!/usr/bin/python

#########################################################################
# PDF2DJVU version 0.12 -- Converts a PDF file to a DJVU file.
#
# Copyright 2005, 2006 Jonathan Hanke            
# Original Author: Jonathan Hanke
# Last updated by Jonathan Hanke on March 4, 2006 
# 
# 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
# (at your option) 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 this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301, USA
#########################################################################
# Version History:
#
#    Version 0.12 -- Padded the page number strings to give correct page orderings
#    Version 0.11 -- Ported from Bash to Python
#    Version 0.10 -- Original Bash script
#
#########################################################################
#  To Do:
#      - Add a flag to reinstate the page rotation feature
#
#########################################################################

import os, sys, time, tempfile, string

## Print the current version
print "Using pdf2dj v0.12 -- Written by Jonathan Hanke, last modified 3/4/2006"


## Get an argument list from the command line
arg_list = sys.argv[1:]


## Filter for only ".pdf" suffixes
pdf_args = [ name  for name in arg_list if name.endswith(".pdf") ]
print " There are", len(pdf_args), " PDF files to convert."


###############
## FILE LOOP ##
###############
for pdf_filename in pdf_args:

    ## Make the temporary directory
    tmp_dir = tempfile.mkdtemp("", pdf_filename + "__", "/tmp")

    ## (Partially) protect the filename(s) for Bash
    bashpdf_filename = pdf_filename.replace("(", "\(").replace(")", "\)")          # Protect parentheses
    bashpdf_filename = bashpdf_filename.replace("'", "\'").replace('"', '\"')  # Protect single and double quotes
    #bashtmp_dir = tmp_dir
    bashtmp_dir = tmp_dir.replace("(", "\(").replace(")", "\)")          # Protect parentheses
    bashtmp_dir = bashtmp_dir.replace("'", "\'").replace('"', '\"')      # Protect single and double quotes

    ## Find the number of pages in the pdf file    
    pages_text = os.popen("pdfinfo " + bashpdf_filename + " | grep 'Pages:'").readline()
    num_of_pages = int(pages_text.lstrip("Pages:").strip())
    print "There are", num_of_pages, "pages in the PDF file", pdf_filename


    ###############
    ## PAGE LOOP ##
    ###############
    for num in range(1, num_of_pages + 1):
        num_str = string.zfill(num, 8)  # Allows up to 10 million (correctly ordered) pages 

        if os.path.exists(tmp_dir + "/" + num_str + ".djvu"):
            print "  Found page ", num, " -- ", time.asctime()

        else:
            print "  Generating page ", num, " -- ", time.asctime()

            # Extract the current page
            extracted_pagename = bashtmp_dir + "/newpage_" + num_str 
            GS_Basic = "gs -q -r300 -dNOPAUSE -dBATCH -dSAFER -sDEVICE=ppmraw"
            GS_Custom = "-dFirstPage=" + str(num) + " -dLastPage=" + str(num) + " -sOutputFile=" + extracted_pagename  + " -- " + bashpdf_filename
            os.system(GS_Basic + " " + GS_Custom)


#            ######################################
#            ## ADD THIS FUNCTIONALITY AS A FLAG ##
#            ######################################
#
#            # Rotate CCW by the number of degrees in the second argument!
#            if [ $# = 1 ]; then
#                 ## echo "    No extra operations!"
#                 sleep 0   #Dummy command
#            else
#                 ## echo "    Rotating clockwise by $2 degrees!"
#                 convert -rotate $2 $tmp_dir/newpage_$num $tmp_dir/newpage_$num-rot$2.ppm
#                 rm -f $tmp_dir/newpage_$num         # Needed to ensure that we only convert the rotated image!
#            fi



            # Convert the page djvu format, then remove it
            converted_pagename = bashtmp_dir + "/" + num_str + ".djvu"
            os.system("cpaldjvu -dpi 300 " + extracted_pagename + " " + converted_pagename)
            os.system("rm -f " + extracted_pagename)
            

    # Assemble each multi-page djvu document
    djvu_filename  = bashpdf_filename.rstrip(".pdf") + ".djvu"  # This is the filename with .pdf replaced by .djvu
    os.system("djvm -c " + djvu_filename + " " + bashtmp_dir + "/*.djvu")


    # Remove the temporary directory
    os.system("rm -rf " + bashtmp_dir)