#! /usr/bin/env python
# -*- coding: ISO-8859-15 -*-

# A banner generator for PyKota
#
# PyKota - Print Quotas for CUPS and LPRng
#
# (c) 2003-2004 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 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
#
# $Id$
#
# $Log$
# Revision 1.8  2004/11/17 13:12:04  jalet
# Implemented the --savetoner command line option
#
# Revision 1.7  2004/11/15 22:29:01  jalet
# Moved title and filename to the left to free some space.
#
# Revision 1.6  2004/11/15 22:20:27  jalet
# Now outputs strings as-is, and not title-ized
#
# Revision 1.5  2004/11/15 22:01:34  jalet
# Improved banner handling.
# Fix for raw printing and banners.
#
# Revision 1.4  2004/11/15 19:59:34  jalet
# PyKota banners now basically work !
#
# Revision 1.3  2004/11/12 23:46:44  jalet
# Heavy work on pkbanner. Not finished yet though, but mostly works.
#
# Revision 1.2  2004/11/11 14:25:48  jalet
# Added some TODO comments
#
# Revision 1.1  2004/11/10 22:48:47  jalet
# Banner generator's skeleton added
#
#
#

import sys
import os
import time
import cStringIO
import popen2

try :
    from reportlab.pdfgen import canvas
    from reportlab.lib import pagesizes
    from reportlab.lib.units import cm
except ImportError :    
    hasRL = 0
else :    
    hasRL = 1
    
try :
    import PIL.Image 
except ImportError :    
    hasPIL = 0
else :    
    hasPIL = 1
    
from pykota.tool import Tool, PyKotaToolError, crashed, N_

__doc__ = N_("""pkbanner v%s (c) 2003-2004 C@LL - Conseil Internet & Logiciels Libres

Generates banners.

command line usage :

  pkbanner  [options]  [files]

options :

  -v | --version       Prints pkbanner's version number then exits.
  -h | --help          Prints this message then exits.
  
  -l | --logo img      Use the image as the banner's logo. The logo will
                       be drawn at the top center of the page. The default
                       logo is /usr/share/pykota/logos/pykota.jpeg
                       
  -p | --pagesize sz   Sets sz as the page size. Most well known
                       page sizes are recognized, like 'A4' or 'Letter'
                       to name a few. The default size is A4.
  
  -s | --savetoner s   Sets the text luminosity factor to d%%. This can be 
                       used to save toner. The default value is 0, which
                       means that no toner saving will be done.
  
  -u | --url u         Uses u as an url to be written at the bottom of 
                       the banner page. The default url is :
                       http://www.librelogiciel.com/software/
  
examples :                              

  Using pkbanner directly from the command line is not recommended,
  excepted for testing purposes. You should use pkbanner in the
  'startingbanner' or 'endingbanner' directives in pykota.conf
  
  For this reason, there's no example.

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., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.

Please e-mail bugs to: %s""")
        
class PyKotaBanner(Tool) :        
    """A class for pkbanner."""
    def getPageSize(self, pgsize) :
        """Returns the correct page size or None if not found."""
        try :
            return getattr(pagesizes, pgsize.upper())
        except AttributeError :    
            try :
                return getattr(pagesizes, pgsize.lower())
            except AttributeError :
                pass
                
    def getVar(self, varname) :            
        """Extracts a variable from the environment and returns its value or 'Unknown' in the current locale."""
        return os.environ.get(varname) or _("Unknown")
        
    def printVar(self, canvas, x, y, label, value, size, savetoner) :
        """Outputs a variable onto the PDF canvas.
        
           Returns the number of points to substract to current Y coordinate.
        """   
        canvas.saveState()
        canvas.setFont("Helvetica-Bold", size)
        (r, g, b) =  [ color + (savetoner * (1.0 - color)) for color in (0, 0, 0) ] # Black * savetoner
        canvas.setFillColorRGB(r, g, b)
        message = "%s :" % _(label)
        canvas.drawRightString(x, y, message)
        canvas.setFont("Courier-Bold", size)
        (r, g, b) =  [ color + (savetoner * (1.0 - color)) for color in (1, 0, 0) ] # Red * savetoner
        canvas.setFillColorRGB(r, g, b)
        canvas.drawString(x + 0.5*cm, y, value)
        canvas.restoreState()
        return (size + 4)
    
    def genPDF(self, pagesize, logo, url, savetoner) :
        """Generates the banner in PDF format, return the PDF document as a string."""
        
        document = cStringIO.StringIO()
        c = canvas.Canvas(document, pagesize=pagesize, pageCompression=1)
        
        c.setAuthor("Jerome Alet")
        c.setTitle("PyKota generated Banner")
        c.setSubject("This is a print banner generated with PyKota")
        
        xcenter = pagesize[0] / 2.0
        ycenter = pagesize[1] / 2.0
                    
        ypos = pagesize[1] - (2 * cm)            
        
        if logo :
            try :    
                imglogo = PIL.Image.open(logo)
            except :    
                self.printInfo("Unable to open image %s" % logo, "warn")
            else :
                (width, height) = imglogo.size
                multi = float(width) / (8 * cm) 
                width = float(width) / multi
                height = float(height) / multi
                xpos = xcenter - (width / 2.0)
                ypos -= height
                c.drawImage(logo, xpos, ypos, width, height)
        
        # New top
        xpos = pagesize[0] / 5.0
        ypos -= (1 * cm) + 20
        
        printername = self.getVar("PYKOTAPRINTERNAME")
        username = self.getVar("PYKOTAUSERNAME")
        accountbanner = self.config.getAccountBanner(printername)
        
        # Outputs the username
        ypos -= self.printVar(c, xcenter, ypos, _("Username"), username, 20, savetoner) 
        
        # Printer and Job Id
        job = "%s - %s" % (printername, self.getVar("PYKOTAJOBID"))
        ypos -= self.printVar(c, xcenter, ypos, _("Job"), job, 14, savetoner) 
        
        # Current date (TODO : at the time the banner was printed ! Change this to job's submission date)
        datetime = time.strftime("%c", time.localtime())
        ypos -= self.printVar(c, xcenter, ypos, _("Date"), datetime, 14, savetoner) 
        
        # Result of the print job
        action = self.getVar("PYKOTAACTION")
        if action == "ALLOW" :
            action = _("Allowed")
        elif action == "DENY" :    
            action = _("Denied")
        elif action == "WARN" :    
            action = _("Allowed with Warning")
        ypos -= self.printVar(c, xcenter, ypos, _("Result"), action, 14, savetoner) 
        
        # skip some space
        ypos -= 20
        
        # Outputs title and filename
        # We put them at x=0.25*pagewidth so that the line is long enough to hold them
        title = self.getVar("PYKOTATITLE")
        ypos -= self.printVar(c, xcenter / 2.0, ypos, _("Title"), title, 10, savetoner) 
        
        filename = self.getVar("PYKOTAFILENAME")
        ypos -= self.printVar(c, xcenter / 2.0, ypos, _("Filename"), filename, 10, savetoner) 
        
        # skip some space
        ypos -= 20
        
        # Now outputs the user's account balance or page counter
        ypos -= self.printVar(c, xcenter, ypos, _("Pages printed so far on %s") % printername, self.getVar("PYKOTAPAGECOUNTER"), 14, savetoner) 
        limitby = self.getVar("PYKOTALIMITBY")
        if limitby == "balance" :  
            ypos -= self.printVar(c, xcenter, ypos, _("Account balance"), self.getVar("PYKOTABALANCE"), 14, savetoner) 
        else :
            ypos -= self.printVar(c, xcenter, ypos, _("Soft Limit"), self.getVar("PYKOTASOFTLIMIT"), 14, savetoner) 
            ypos -= self.printVar(c, xcenter, ypos, _("Hard Limit"), self.getVar("PYKOTAHARDLIMIT"), 14, savetoner) 
            ypos -= self.printVar(c, xcenter, ypos, _("Date Limit"), self.getVar("PYKOTADATELIMIT"), 14, savetoner) 
            
        # URL
        if url :
            c.saveState()
            c.setFont("Courier-Bold", 16)
            (r, g, b) =  [ color + (savetoner * (1.0 - color)) for color in (0, 0, 1) ] # Blue * savetoner
            c.setFillColorRGB(r, g, b)
            c.drawCentredString(xcenter, 2 * cm, url)
            c.restoreState()
        
        c.showPage()
        c.save()
        return document.getvalue()
        
    def main(self, files, options) :
        """Generates a banner."""
        if not hasRL :
            raise PyKotaToolError, "The ReportLab module is missing. Download it from http://www.reportlab.org"
        if not hasPIL :
            raise PyKotaToolError, "The Python Imaging Library is missing. Download it from http://www.pythonware.com/downloads"
            
        try :
            savetoner = int(options["savetoner"])
            if (savetoner < 0) or (savetoner > 99) :
                raise ValueError, _("Allowed range is (0..99)")
            savetoner /= 100.0    
        except (TypeError, ValueError), msg :
            self.printInfo(_("Invalid 'savetoner' option %s : %s") % (options["savetoner"], msg), "warn")
            savetoner = 0.0
            
        pagesize = self.getPageSize(options["pagesize"])
        if pagesize is None :
            pagesize = self.getPageSize("a4")
            self.printInfo(_("Invalid 'pagesize' option %s, defaulting to A4.") % options["pagesize"], "warn")
            
        self.logdebug("Generating the banner in PDF format...")    
        doc = self.genPDF(pagesize, options["logo"].strip(), options["url"].strip(), savetoner)
        
        self.logdebug("Converting the banner to PostScript...")    
        os.environ["PATH"] = "%s:/bin:/usr/bin:/usr/local/bin:/opt/bin:/sbin:/usr/sbin" % os.environ.get("PATH", "")
        child = popen2.Popen3("gs -q -dNOPAUSE -dBATCH -dPARANOIDSAFER -sDEVICE=pswrite -sOutputFile=- - 2>/tmp/errgs")
        child.tochild.write(doc)
        child.tochild.close()
        sys.stdout.write(child.fromchild.read())
        sys.stdout.flush()
        child.fromchild.close()
        status = child.wait()
        if os.WIFEXITED(status) :
            status = os.WEXITSTATUS(status)
        self.logdebug("PDF to PostScript converter exit code is %s" % str(status))
        self.logdebug("Banner completed.")
        return status

if __name__ == "__main__" :
    # TODO : --papertray : to print banners on a different paper (colored for example)
    retcode = 0
    try :
        defaults = { \
                     "savetoner" : "100", \
                     "pagesize" : "a4", \
                     "logo" : "/usr/share/pykota/logos/pykota.jpeg",
                     "url" : "http://www.librelogiciel.com/software/",
                   }
        short_options = "vhs:l:p:u:"
        long_options = ["help", "version", "savetoner=", "pagesize=", "logo=", "url="]
        
        # Initializes the command line tool
        banner = PyKotaBanner(doc=__doc__)
        
        # parse and checks the command line
        (options, args) = banner.parseCommandline(sys.argv[1:], short_options, long_options, allownothing=1)
        
        # sets long options
        options["help"] = options["h"] or options["help"]
        options["version"] = options["v"] or options["version"]
        options["savetoner"] = options["s"] or options["savetoner"] or defaults["savetoner"]
        options["pagesize"] = options["p"] or options["pagesize"] or defaults["pagesize"]
        options["url"] = options["u"] or options["url"] or defaults["url"]
        
        options["logo"] = options["l"] or options["logo"]
        if options["logo"] is None : # Allows --logo="" to disable the logo entirely
            options["logo"] = defaults["logo"]  
        
        if options["help"] :
            banner.display_usage_and_quit()
        elif options["version"] :
            banner.display_version_and_quit()
        else :
            retcode = banner.main(args, options)
    except SystemExit :        
        pass
    except :
        try :
            banner.crashed("pkbanner failed")
        except :    
            crashed("pkbanner failed")
        retcode = -1
        
    sys.exit(retcode)