Edit book: Allow editing of KEPUB files

Note that all Kobo markup is removed when opening the file and
automatically re-inserted when saving it.

manual/edit.rst

@@ -4,10 +4,10 @@ Editing e-books
 ========================
 
 calibre has an integrated e-book editor that can be used to edit books in the
-EPUB and AZW3 (Kindle) formats. The editor shows you the HTML and CSS that is
-used internally inside the book files, with a live preview that updates as you
-make changes. It also contains various automated tools to perform common
-cleanup and fixing tasks.
+EPUB, KEPUB (Kobo) and AZW3 (Kindle) formats. The editor shows you the HTML and
+CSS that is used internally inside the book files, with a live preview that
+updates as you make changes. It also contains various automated tools to
+perform common cleanup and fixing tasks.
 
 You can use this editor by right clicking on any book in calibre and selecting
 :guilabel:`Edit book`.

src/calibre/ebooks/oeb/polish/check/main.py

@@ -5,6 +5,7 @@ __license__ = 'GPL v3'
 __copyright__ = '2013, Kovid Goyal <kovid at kovidgoyal.net>'
 
 from collections import namedtuple
+from functools import partial
 
 from calibre.ebooks.oeb.base import OEB_DOCS, OEB_STYLES
 from calibre.ebooks.oeb.polish.check.base import WARN, run_checkers
@@ -65,8 +66,8 @@ def run_checks(container):
             items = raster_images
         if items is not None:
             items.append((name, mt, container.raw_data(name, decode=decode)))
-    if container.book_type == 'epub':
-        errors.extend(run_checkers(check_html_size, html_items))
+    if container.MAX_HTML_FILE_SIZE:
+        errors.extend(run_checkers(partial(check_html_size, max_size=container.MAX_HTML_FILE_SIZE), html_items))
     errors.extend(run_checkers(check_xml_parsing, xml_items))
     errors.extend(run_checkers(check_xml_parsing, html_items))
     errors.extend(run_checkers(check_raster_images, raster_images))

src/calibre/ebooks/oeb/polish/check/parsing.py

@@ -154,12 +154,11 @@ class EscapedName(BaseError):
 class TooLarge(BaseError):
 
     level = INFO
-    MAX_SIZE = 260 *1024
-    HELP = _('This HTML file is larger than %s. Too large HTML files can cause performance problems'
-             ' on some e-book readers. Consider splitting this file into smaller sections.') % human_readable(MAX_SIZE)
 
-    def __init__(self, name):
+    def __init__(self, name, max_size):
         BaseError.__init__(self, _('File too large'), name)
+        self.HELP = _('This HTML file is larger than {}. Too large HTML files can cause performance problems'
+                ' on some e-book readers. Consider splitting this file into smaller sections.').format(human_readable(max_size))
 
 
 class BadEntity(BaseError):
@@ -244,10 +243,10 @@ class EntitityProcessor:
         return b' ' * len(m.group())
 
 
-def check_html_size(name, mt, raw):
+def check_html_size(name, mt, raw, max_size=0):
     errors = []
-    if len(raw) > TooLarge.MAX_SIZE:
-        errors.append(TooLarge(name))
+    if max_size and len(raw) > max_size:
+        errors.append(TooLarge(name, max_size))
     return errors
 
 

src/calibre/ebooks/oeb/polish/container.py

@@ -49,7 +49,7 @@ from calibre.ebooks.oeb.polish.errors import DRMError, InvalidBook
 from calibre.ebooks.oeb.polish.parsing import decode_xml
 from calibre.ebooks.oeb.polish.parsing import parse as parse_html_tweak
 from calibre.ebooks.oeb.polish.utils import OEB_FONTS, CommentFinder, PositionFinder, adjust_mime_for_epub, guess_type, insert_self_closing, parse_css
-from calibre.ptempfile import PersistentTemporaryDirectory, PersistentTemporaryFile
+from calibre.ptempfile import PersistentTemporaryDirectory, PersistentTemporaryFile, TemporaryDirectory
 from calibre.utils.filenames import hardlink_file, nlinks_file, retry_on_fail
 from calibre.utils.ipc.simple_worker import WorkerError, fork_job
 from calibre.utils.logging import default_log
@@ -85,14 +85,14 @@ def clone_dir(src, dest):
                 shutil.copy2(spath, dpath)
 
 
-def clone_container(container, dest_dir):
+def clone_container(container, dest_dir, container_class=None):
     ' Efficiently clone a container using hard links '
     dest_dir = os.path.abspath(os.path.realpath(dest_dir))
     clone_data = container.clone_data(dest_dir)
-    cls = type(container)
-    if cls is Container:
-        return cls(None, None, container.log, clone_data=clone_data)
-    return cls(None, container.log, clone_data=clone_data)
+    container_class = container_class or type(container)
+    if container_class is Container:
+        return container_class(None, None, container.log, clone_data=clone_data)
+    return container_class(None, container.log, clone_data=clone_data)
 
 
 def name_to_abspath(name, root):
@@ -229,6 +229,7 @@ class Container(ContainerBase):  # {{{
 
     SUPPORTS_TITLEPAGES = True
     SUPPORTS_FILENAMES = True
+    MAX_HTML_FILE_SIZE = 0
 
     @property
     def book_type_for_display(self):
@@ -1121,6 +1122,7 @@ def walk_dir(basedir):
 class EpubContainer(Container):
 
     book_type = 'epub'
+    MAX_HTML_FILE_SIZE = 260 * 1024
 
     @property
     def book_type_for_display(self):
@@ -1377,6 +1379,12 @@ class EpubContainer(Container):
                 f.write(decrypt_font_data(key, data, alg))
         if outpath is None:
             outpath = self.pathtoepub
+        self.commit_epub(outpath)
+        for name, data in iteritems(restore_fonts):
+            with self.open(name, 'wb') as f:
+                f.write(data)
+
+    def commit_epub(self, outpath: str) -> None:
         if self.is_dir:
             # First remove items from the source dir that do not exist any more
             for is_root, dirpath, fname in walk_dir(self.pathtoepub):
@@ -1413,9 +1421,6 @@ class EpubContainer(Container):
                     et = et.encode('ascii')
                 f.write(et)
             zip_rebuilder(self.root, outpath)
-            for name, data in iteritems(restore_fonts):
-                with self.open(name, 'wb') as f:
-                    f.write(data)
 
     @property
     def path_to_ebook(self):
@@ -1428,6 +1433,26 @@ class EpubContainer(Container):
 # }}}
 
 
+class KEPUBContainer(EpubContainer):
+    book_type = 'kepub'
+    MAX_HTML_FILE_SIZE = 512 * 1024
+
+    def __init__(self, pathtokepub, log, clone_data=None, tdir=None):
+        super().__init__(pathtokepub, log=log, clone_data=clone_data, tdir=tdir)
+        from calibre.ebooks.oeb.polish.kepubify import unkepubify_container
+        Container.commit(self, keep_parsed=True)
+        unkepubify_container(self)
+
+    def commit_epub(self, outpath: str) -> None:
+        if self.is_dir:
+            return super().commit_epub(outpath)
+        from calibre.ebooks.oeb.polish.kepubify import Options, kepubify_container
+        with TemporaryDirectory() as tdir:
+            container = clone_container(self, tdir, container_class=EpubContainer)
+            kepubify_container(container, Options())
+            container.commit(outpath)
+
+
 # AZW3 {{{
 
 class InvalidMobi(InvalidBook):
@@ -1590,8 +1615,13 @@ def get_container(path, log=None, tdir=None, tweak_mode=False, ebook_cls=None) -
         isdir = False
     own_tdir = not tdir
     if ebook_cls is None:
-        ebook_cls = (AZW3Container if path.rpartition('.')[-1].lower() in {'azw3', 'mobi', 'original_azw3', 'original_mobi'} and not isdir
-                else EpubContainer)
+        ext = path.rpartition('.')[-1].lower()
+        ebook_cls = EpubContainer
+        if not isdir:
+            if ext in {'azw3', 'mobi', 'original_azw3', 'original_mobi'}:
+                ebook_cls = AZW3Container
+            elif ext in {'kepub', 'original_kepub'}:
+                ebook_cls = KEPUBContainer
     if own_tdir:
         tdir = PersistentTemporaryDirectory(f'_{ebook_cls.book_type}_container')
     try:

src/calibre/ebooks/oeb/polish/kepubify.py

@@ -450,14 +450,16 @@ def process_path(path: str, kobo_js_href: str, metadata_lang: str, opts: Options
 def do_work_in_parallel(container: Container, kobo_js_name: str, opts: Options, metadata_lang: str, max_workers: int) -> None:
     names_that_need_work = tuple(name for name, mt in container.mime_map.items() if mt in OEB_DOCS or mt in OEB_STYLES)
     num_workers = calculate_number_of_workers(names_that_need_work, container, max_workers)
-    paths = tuple(map(container.name_to_abspath, names_that_need_work))
+    def name_to_abspath(name: str) -> str:
+        return container.get_file_path_for_processing(name, allow_modification=True)
+
     if num_workers < 2:
         for name in names_that_need_work:
-            process_path(container.name_to_abspath(name), container.name_to_href(kobo_js_name, name), metadata_lang, opts, container.mime_map[name])
+            process_path(name_to_abspath(name), container.name_to_href(kobo_js_name, name), metadata_lang, opts, container.mime_map[name])
     else:
         with ThreadPoolExecutor(max_workers=num_workers) as executor:
             futures = tuple(executor.submit(
-                process_path, container.name_to_abspath(name), container.name_to_href(kobo_js_name, name),
+                process_path, name_to_abspath(name), container.name_to_href(kobo_js_name, name),
                 metadata_lang, opts, container.mime_map[name]) for name in names_that_need_work)
             for future in futures:
                 future.result()

src/calibre/ebooks/oeb/polish/main.py

@@ -51,7 +51,7 @@ CUSTOMIZATION = {
     'remove_ncx': True,
 }
 
-SUPPORTED = {'EPUB', 'AZW3'}
+SUPPORTED = {'EPUB', 'AZW3', 'KEPUB'}
 
 # Help {{{
 HELP = {'about': _(

src/calibre/ebooks/oeb/polish/tests/kepubify.py

@@ -3,7 +3,7 @@
 
 
 from calibre.ebooks.oeb.base import OEB_DOCS, OEB_STYLES
-from calibre.ebooks.oeb.polish.container import get_container
+from calibre.ebooks.oeb.polish.container import EpubContainer, get_container
 from calibre.ebooks.oeb.polish.kepubify import (
     CSS_COMMENT_COOKIE,
     DUMMY_COVER_IMAGE_NAME,
@@ -27,7 +27,7 @@ class KepubifyTests(BaseTest):
             path = get_book_for_kepubify(has_cover=has_cover, epub_version=epub_version)
             opts = Options()._replace(remove_widows_and_orphans=True, remove_at_page_rules=True)
             outpath = kepubify_path(path, opts=opts, allow_overwrite=True)
-            c = get_container(outpath, tweak_mode=True)
+            c = get_container(outpath, tweak_mode=True, ebook_cls=EpubContainer)
             spine_names = tuple(n for n, is_linear in c.spine_names)
             cname = 'titlepage.xhtml' if has_cover else f'{DUMMY_TITLE_PAGE_NAME}.xhtml'
             self.assertEqual(spine_names, (cname, 'index_split_000.html', 'index_split_001.html'))

src/calibre/ebooks/oeb/polish/tts.py

@@ -452,7 +452,7 @@ def remove_embedded_tts(container):
 
 def embed_tts(container, report_progress=None, callback_to_download_voices=None):
     report_progress = report_progress or ReportProgress()
-    if container.book_type != 'epub':
+    if container.book_type not in ('epub', 'kepub'):
         raise UnsupportedContainerType(_('Only the EPUB format has support for embedding speech overlay audio'))
     if container.opf_version_parsed[0] < 3:
         if report_progress(_('Updating book internals'), '', 0, 0):

src/calibre/ebooks/oeb/polish/upgrade.py

@@ -169,7 +169,7 @@ def epub_2_to_3(container, report, previous_nav=None, remove_ncx=True):
 
 
 def upgrade_book(container, report, remove_ncx=True):
-    if container.book_type != 'epub' or container.opf_version_parsed.major >= 3:
+    if container.book_type not in ('epub', 'kepub') or container.opf_version_parsed.major >= 3:
         report(_('No upgrade needed'))
         return False
     epub_2_to_3(container, report, remove_ncx=remove_ncx)