if isinstance(data, str):

return data

elif isinstance(data, unicode):

if u'\xfffd' in data:

raise AssertionError('Uknown character in %r. Please set up system '

'locale properly, or use ASCII only.' % data)

return data.encode(calibre.preferred_encoding)

else:

if (len(argv) > 1 and argv[1] in ('--help', '-h')):

print usage(argv[0])

sys.exit(0)

if len(argv) > 2:

print >>sys.stderr, usage()

sys.exit(1)

dbdir = argv[1].rstrip(os.sep) if len(argv) > 1 else '.'

dbname = os.path.join(dbdir, 'metadata.db')

dbpath = os.path.abspath(dbname)

print >>sys.stderr, 'info: Reading Calibre database: ' + dbpath

if not os.path.isfile(dbname):

raise AssertionError('Calibre database missing: %s' % dbpath)

dbdirpath = os.path.dirname(dbpath)

# Reads the whole metadata.db to memory.

db = database2.LibraryDatabase2(dbdirpath)

fm = db.FIELD_MAP

fm_path = fm['path']

# TODO(pts): Do we have to replace / with os.sep on Windows?

book_path_items = [(i, encode_unicode(row[fm_path]))

for i, row in enumerate(db.data._data) if row is not None]

print >>sys.stderr, 'info: Found %d book%s in metadata.db.' % (

len(book_path_items), 's' * (len(book_path_items) != 1))

book_opf_items = []

for i, book_path in book_path_items:

opf_path = os.path.join(dbdirpath, book_path, 'metadata.opf')

if not os.path.exists(opf_path):

book_opf_items.append((i, opf_path))

print >>sys.stderr, 'info: Found %d book%s with missing metadata.opf.' % (

len(book_opf_items), 's' * (len(book_opf_items) != 1))

# TODO(pts): Find directories not corresponding to any books in the database.

for i, opf_path in book_opf_items:

mi = db.get_metadata(i, index_is_id=True)

print >>sys.stderr, 'info: Creating metadata.opf: %s' % opf_path

# This creates a very different .opf.

# opf_creator = opf2.OPFCreator(os.path.dirname(opf_path), mi)

# sio = cStringIO.StringIO()

# opf_creator.render(sio)

if mi.has_cover and not mi.cover:

mi.cover = 'cover.jpg'

data = opf2.metadata_to_opf(mi)

with open(opf_path, 'wb') as f:

f.write(data)