Initial import

ebook_converter/ebooks/metadata/utils.py

@@ -0,0 +1,104 @@
+#!/usr/bin/env python2
+# vim:fileencoding=utf-8
+# License: GPLv3 Copyright: 2016, Kovid Goyal <kovid at kovidgoyal.net>
+
+from __future__ import absolute_import, division, print_function, unicode_literals
+
+from collections import namedtuple
+
+from calibre.ebooks.chardet import xml_to_unicode
+from calibre.ebooks.oeb.base import OPF
+from calibre.ebooks.oeb.polish.utils import guess_type
+from calibre.spell import parse_lang_code
+from calibre.utils.cleantext import clean_xml_chars
+from calibre.utils.localization import lang_as_iso639_1
+from calibre.utils.xml_parse import safe_xml_fromstring
+from polyglot.builtins import filter, map
+
+OPFVersion = namedtuple('OPFVersion', 'major minor patch')
+
+
+def parse_opf_version(raw):
+    parts = (raw or '').split('.')
+    try:
+        major = int(parts[0])
+    except Exception:
+        return OPFVersion(2, 0, 0)
+    try:
+        v = list(map(int, raw.split('.')))
+    except Exception:
+        v = [major, 0, 0]
+    while len(v) < 3:
+        v.append(0)
+    v = v[:3]
+    return OPFVersion(*v)
+
+
+def parse_opf(stream_or_path):
+    stream = stream_or_path
+    if not hasattr(stream, 'read'):
+        stream = open(stream, 'rb')
+    raw = stream.read()
+    if not raw:
+        raise ValueError('Empty file: '+getattr(stream, 'name', 'stream'))
+    raw, encoding = xml_to_unicode(raw, strip_encoding_pats=True, resolve_entities=True, assume_utf8=True)
+    raw = raw[raw.find('<'):]
+    root = safe_xml_fromstring(clean_xml_chars(raw))
+    if root is None:
+        raise ValueError('Not an OPF file')
+    return root
+
+
+def normalize_languages(opf_languages, mi_languages):
+    ' Preserve original country codes and use 2-letter lang codes where possible '
+    def parse(x):
+        try:
+            return parse_lang_code(x)
+        except ValueError:
+            return None
+    opf_languages = filter(None, map(parse, opf_languages))
+    cc_map = {c.langcode:c.countrycode for c in opf_languages}
+    mi_languages = filter(None, map(parse, mi_languages))
+
+    def norm(x):
+        lc = x.langcode
+        cc = x.countrycode or cc_map.get(lc, None)
+        lc = lang_as_iso639_1(lc) or lc
+        if cc:
+            lc += '-' + cc
+        return lc
+    return list(map(norm, mi_languages))
+
+
+def ensure_unique(template, existing):
+    b, e = template.rpartition('.')[::2]
+    if b and e:
+        e = '.' + e
+    else:
+        b, e = template, ''
+    q = template
+    c = 0
+    while q in existing:
+        c += 1
+        q = '%s-%d%s' % (b, c, e)
+    return q
+
+
+def create_manifest_item(root, href_template, id_template, media_type=None):
+    all_ids = frozenset(root.xpath('//*/@id'))
+    all_hrefs = frozenset(root.xpath('//*/@href'))
+    href = ensure_unique(href_template, all_hrefs)
+    item_id = ensure_unique(id_template, all_ids)
+    manifest = root.find(OPF('manifest'))
+    if manifest is not None:
+        i = manifest.makeelement(OPF('item'))
+        i.set('href', href), i.set('id', item_id)
+        i.set('media-type', media_type or guess_type(href_template))
+        manifest.append(i)
+        return i
+
+
+def pretty_print_opf(root):
+    from calibre.ebooks.oeb.polish.pretty import pretty_opf, pretty_xml_tree
+    pretty_opf(root)
+    pretty_xml_tree(root)