calibre-web/cps/epub.py

# -*- coding: utf-8 -*-

#  This file is part of the Calibre-Web (https://github.com/janeczku/calibre-web)
#    Copyright (C) 2018 lemmsh, Kennyl, Kyosfonica, matthazinski
#
#  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/>.

import os
import zipfile
from lxml import etree

from . import isoLanguages, cover
from .helper import split_authors
from .constants import BookMeta


def _extract_cover(zip_file, cover_file, cover_path, tmp_file_name):
    if cover_file is None:
        return None
    else:
        cf = extension = None
        zip_cover_path = os.path.join(cover_path, cover_file).replace('\\', '/')

        prefix = os.path.splitext(tmp_file_name)[0]
        tmp_cover_name = prefix + '.' + os.path.basename(zip_cover_path)
        ext = os.path.splitext(tmp_cover_name)
        if len(ext) > 1:
            extension = ext[1].lower()
        if extension in cover.COVER_EXTENSIONS:
            cf = zip_file.read(zip_cover_path)
        return cover.cover_processing(tmp_file_name, cf, extension)


def get_epub_info(tmp_file_path, original_file_name, original_file_extension):
    ns = {
        'n': 'urn:oasis:names:tc:opendocument:xmlns:container',
        'pkg': 'http://www.idpf.org/2007/opf',
        'dc': 'http://purl.org/dc/elements/1.1/'
    }

    epub_zip = zipfile.ZipFile(tmp_file_path)

    txt = epub_zip.read('META-INF/container.xml')
    tree = etree.fromstring(txt)
    cf_name = tree.xpath('n:rootfiles/n:rootfile/@full-path', namespaces=ns)[0]
    cf = epub_zip.read(cf_name)
    tree = etree.fromstring(cf)

    cover_path = os.path.dirname(cf_name)

    p = tree.xpath('/pkg:package/pkg:metadata', namespaces=ns)[0]

    epub_metadata = {}

    for s in ['title', 'description', 'creator', 'language', 'subject']:
        tmp = p.xpath('dc:%s/text()' % s, namespaces=ns)
        if len(tmp) > 0:
            if s == 'creator':
                epub_metadata[s] = ' & '.join(split_authors(tmp))
            elif s == 'subject':
                epub_metadata[s] = ', '.join(tmp)
            else:
                epub_metadata[s] = tmp[0]
        else:
            epub_metadata[s] = 'Unknown'

    if epub_metadata['subject'] == 'Unknown':
        epub_metadata['subject'] = ''

    if epub_metadata['description'] == u'Unknown':
        description = tree.xpath("//*[local-name() = 'description']/text()")
        if len(description) > 0:
            epub_metadata['description'] = description
        else:
            epub_metadata['description'] = ""

    lang = epub_metadata['language'].split('-', 1)[0].lower()
    epub_metadata['language'] = isoLanguages.get_lang3(lang)

    epub_metadata = parse_epub_series(ns, tree, epub_metadata)

    cover_file = parse_epub_cover(ns, tree, epub_zip, cover_path, tmp_file_path)

    if not epub_metadata['title']:
        title = original_file_name
    else:
        title = epub_metadata['title']

    return BookMeta(
        file_path=tmp_file_path,
        extension=original_file_extension,
        title=title.encode('utf-8').decode('utf-8'),
        author=epub_metadata['creator'].encode('utf-8').decode('utf-8'),
        cover=cover_file,
        description=epub_metadata['description'],
        tags=epub_metadata['subject'].encode('utf-8').decode('utf-8'),
        series=epub_metadata['series'].encode('utf-8').decode('utf-8'),
        series_id=epub_metadata['series_id'].encode('utf-8').decode('utf-8'),
        languages=epub_metadata['language'],
        publisher="")


def parse_epub_cover(ns, tree, epub_zip, cover_path, tmp_file_path):
    cover_section = tree.xpath("/pkg:package/pkg:manifest/pkg:item[@id='cover-image']/@href", namespaces=ns)
    cover_file = None
    # if len(cover_section) > 0:
    for cs in cover_section:
        cover_file = _extract_cover(epub_zip, cs, cover_path, tmp_file_path)
        if cover_file:
            break
    if not cover_file:
        meta_cover = tree.xpath("/pkg:package/pkg:metadata/pkg:meta[@name='cover']/@content", namespaces=ns)
        if len(meta_cover) > 0:
            cover_section = tree.xpath(
                "/pkg:package/pkg:manifest/pkg:item[@id='"+meta_cover[0]+"']/@href", namespaces=ns)
            if not cover_section:
                cover_section = tree.xpath(
                    "/pkg:package/pkg:manifest/pkg:item[@properties='" + meta_cover[0] + "']/@href", namespaces=ns)
        else:
            cover_section = tree.xpath("/pkg:package/pkg:guide/pkg:reference/@href", namespaces=ns)
        for cs in cover_section:
            filetype = cs.rsplit('.', 1)[-1]
            if filetype == "xhtml" or filetype == "html":  # if cover is (x)html format
                markup = epub_zip.read(os.path.join(cover_path, cs))
                markup_tree = etree.fromstring(markup)
                # no matter xhtml or html with no namespace
                img_src = markup_tree.xpath("//*[local-name() = 'img']/@src")
                # Alternative image source
                if not len(img_src):
                    img_src = markup_tree.xpath("//attribute::*[contains(local-name(), 'href')]")
                if len(img_src):
                    # img_src maybe start with "../"" so fullpath join then relpath to cwd
                    filename = os.path.relpath(os.path.join(os.path.dirname(os.path.join(cover_path, cover_section[0])),
                                                            img_src[0]))
                    cover_file = _extract_cover(epub_zip, filename, "", tmp_file_path)
            else:
                cover_file = _extract_cover(epub_zip, cs, cover_path, tmp_file_path)
            if cover_file: break
    return cover_file


def parse_epub_series(ns, tree, epub_metadata):
    series = tree.xpath("/pkg:package/pkg:metadata/pkg:meta[@name='calibre:series']/@content", namespaces=ns)
    if len(series) > 0:
        epub_metadata['series'] = series[0]
    else:
        epub_metadata['series'] = ''

    series_id = tree.xpath("/pkg:package/pkg:metadata/pkg:meta[@name='calibre:series_index']/@content", namespaces=ns)
    if len(series_id) > 0:
        epub_metadata['series_id'] = series_id[0]
    else:
        epub_metadata['series_id'] = '1'
    return epub_metadata