root / pkpgcounter / trunk / pkpgpdls / plain.py @ 527

#! /usr/bin/env python
# -*- coding: ISO-8859-15 -*-
#
# pkpgcounter : a generic Page Description Language parser
#
# (c) 2003, 2004, 2005, 2006, 2007 Jerome Alet <alet@librelogiciel.com>
# 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 3 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, see <http://www.gnu.org/licenses/>.
#
# $Id$
#

"""This modules implements a page counter for plain text documents."""

import pdlparser
import version

class Parser(pdlparser.PDLParser) :
    """A parser for plain text documents."""
    totiffcommands = [ 'enscript --quiet --portrait --no-header --columns 1 --output - "%(infname)s" | gs -sDEVICE=tiff24nc -dPARANOIDSAFER -dNOPAUSE -dBATCH -dQUIET -r"%(dpi)i" -sOutputFile="%(outfname)s" -',
                       'a2ps --borders 0 --quiet --portrait --no-header --columns 1 --output - "%(infname)s" | gs -sDEVICE=tiff24nc -dPARANOIDSAFER -dNOPAUSE -dBATCH -dQUIET -r"%(dpi)i" -sOutputFile="%(outfname)s" -',
                     ]  
    required = [ "a2ps | enscript", "gs" ]
    openmode = "rU"                 
    def isValid(self) :    
        """Returns True if data is plain text, else False.
        
           It's hard to detect a plain text file, so we just try to
           extract lines from the first block (sufficiently large).
           If it's impossible to find one we consider it's not plain text.
        """   
        lines = self.firstblock.split("\r\n")
        if len(lines) == 1 :
            lines = lines[0].split("\r")
            if len(lines) == 1 :
                lines = lines[0].split("\n")
        if len(lines) > 1 :
            self.logdebug("DEBUG: Input file seems to be in the plain text format.")
            return True
        else :    
            return False
            
    def getJobSize(self) :
        """Counts pages in a plain text document."""
        pagesize = 66   # TODO : Does this vary wrt the default page size ?
                        # TODO : /etc/papersize and /etc/paper.config
        pagecount = 0
        linecount = 0
        for line in self.infile :
            if line.endswith("\n") :
                linecount += 1    
                if (linecount > pagesize) :
                    pagecount += 1
                    linecount = 0
                else :    
                    cnt = line.count("\f")
                    if cnt :
                        pagecount += cnt
                        linecount = 0
            else :        
                raise pdlparser.PDLParserError, "Unsupported file format. Please send the file to %s" % version.__authoremail__
        return pagecount + 1    # NB : empty files are catched in isValid()