comic2pdf

#!/usr/bin/env python

# Convert cbr/cbz or a directory of images to a letter sized PDF
#
# (c) 2014 Sudhi Herle <sw-at-herle.net>
# GPLv2
#
# XXX Python doesn't have rarfile in its standard lib; macports
#     doesn't have a ready package. So, we do subprocess
#


import sys, os, os.path
import tempfile
import zipfile, subprocess

from os.path import join, splitext, abspath, basename, dirname

from reportlab.lib.pagesizes import letter
from reportlab.platypus import Image
from reportlab.pdfgen import canvas


Z = os.path.basename(sys.argv[0])

def warn(fmt, *args):
    sfmt = '%s: %s' % (Z, fmt)
    if len(args) > 0:
        s = sfmt % args
    else:
        s = sfmt

    if not s.endswith('\n'):
        s += '\n'

    sys.stdout.flush()
    sys.stderr.write(s)
    sys.stderr.flush()

def die(fmt, *args):
    warn(fmt, *args)
    exit(1)


def rmtree(dir):
    """pythonic rm -rf"""

    for root, dirs, files in os.walk(dir, 0):
        for f in files:
            here  = join(root, f)
            os.unlink(here)

        for d in dirs:
            here  = join(root, d)
            os.rmdir(here)

    os.rmdir(dir)

def run(cmd, *args):
    """Run 'cmd' with optional args. Die if error"""

    v = [cmd] + list(args)
    #print os.getcwd()
    #print ' '.join(v)
    p = subprocess.Popen(v, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    err = p.stderr.readlines()
    ex  = p.wait()
    if ex < 0:
        warn("Process '%s' caught signal %d and died!",
               cmd, -ex)
        if len(err) > 0:
            die(''.join(err))
        else:
            exit(1)

    elif ex > 0:
        warn("Process '%s' exited abnormally (code %d); error follows..", cmd, ex)
        if len(err) > 0:
            die(''.join(err))
        else:
            exit(1)


def unrar(nm, dest):
    """Unrar file into destination 'dest'"""
    pwd = os.getcwd()
    #os.makedirs(dest, 0750)
    os.chdir(dest)
    run('unrar', 'x', nm)
    os.chdir(pwd)

def unzip(nm, dest):
    """Unzip file into destination 'dest'"""
    cf = zipfile.ZipFile(nm)
    cf.extractall(dest)
    cf.close()


_ext = ('jpg', 'jpeg', 'png', 'gif')
ext  = dict([ ('.%s' % x, True) for x in _ext ])
def images(dn):
    """Gather all images in dn"""
    global ext

    extn = ext

    img = []
    for root, dirs, files in os.walk(dn):
        for f in files:
            fn = join(root, f)
            bn, ex = splitext(f)

            if ex.lower() in extn:
                img.append(fn)

    #print "Images:\n\t%s" % ', '.join(img)
    return img


def img2pdf(pdf, imgs):
    """Convert a list of images into a PDF """
    try:
        # put each image into its own page and resize dynamically.
        c = canvas.Canvas(pdf, pagesize=letter)
        for img in imgs:
            i = Image(img)
            c.setPageSize((i.drawWidth, i.drawHeight))
            c.drawImage(img, 0, 0, i.drawWidth, i.drawHeight)
            c.showPage()

        c.save()

    except Exception as ex:
        warn("Exception while converting %s: %s", fn, ex)

def process(fn):
    """Convert a cbr/cbz into a pdf"""

    dn = abspath(tempfile.mkdtemp(dir='.'))

    if fn.endswith('.cbz'):
        unzip(fn, dn)
    elif fn.endswith('.cbr'):
        unrar(fn, dn)
    else:
        die("Don't know how to grok %s", fn)

    imgs   = images(dn)
    bn, ex = splitext(fn)
    pdf    = bn + '.pdf'

    print("%s --> %s" % (basename(fn), basename(pdf)))
    img2pdf(pdf, imgs)

    rmtree(dn)



# XXX Add command line parsing - e.g., destination directory for PDF


def main():

    for f in sys.argv[1:]:
        fn = abspath(f)
        if os.path.isfile(fn):
            process(fn)
        elif os.path.isdir(fn):
            imgs = images(fn)
            dn   = basename(fn)
            pdf  = dn + '.pdf'

            print("%s --> %s" % (dn, basename(pdf)))
            img2pdf(pdf, imgs)


main()

# EOF