2347441308
git-svn-id: svn://svn.cy55.de/Zope3/src/cybertools/trunk@1244 fd906abe-77d9-0310-91a1-e0d9ade77398
81 lines
2.5 KiB
Python
81 lines
2.5 KiB
Python
#
|
|
# Copyright (c) 2006 Helmut Merz helmutm@cy55.de
|
|
#
|
|
# 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 2 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, write to the Free Software
|
|
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
#
|
|
|
|
"""
|
|
Batching implementation.
|
|
|
|
$Id$
|
|
"""
|
|
|
|
import itertools
|
|
from zope.interface import implements
|
|
from interfaces import IBatch
|
|
|
|
|
|
class Batch(object):
|
|
|
|
lastPage = False
|
|
|
|
def __init__(self, iterable, pageIndex=0, size=20, overlap=0, orphan=0):
|
|
if type(iterable) not in (tuple, list):
|
|
iterable = list(iterable)
|
|
self.iterable = iterable
|
|
length = len(self.iterable)
|
|
self.pages = range(0, length, size-overlap)
|
|
if pageIndex >= len(self.pages):
|
|
pageIndex = len(self.pages) - 1
|
|
if pageIndex < 0:
|
|
pageIndex = 0
|
|
self.pageIndex = pageIndex
|
|
self.start = pageIndex * (size - overlap)
|
|
self.size = self.actualSize = size
|
|
self.overlap = overlap
|
|
self.orphan = orphan
|
|
if length == 0: lastPage = 0
|
|
else: lastPage = self.pages[-1]
|
|
lastLen = length - lastPage
|
|
if lastLen <= orphan + overlap:
|
|
if length > 0:
|
|
del self.pages[-1]
|
|
if pageIndex == len(self.pages) - 1: #we're on the last page
|
|
self.actualSize = size + lastLen #take over the orphans
|
|
self.items = self.iterable[self.start:self.start+self.actualSize]
|
|
|
|
def __getitem__(self, idx):
|
|
return self.items[idx]
|
|
|
|
def next(self):
|
|
for item in self.items:
|
|
yield item
|
|
|
|
def __len__(self):
|
|
return len(self.items)
|
|
|
|
def getIndexRelative(self, ridx=1):
|
|
idx = self.pageIndex + ridx
|
|
if idx < 0:
|
|
return 0
|
|
if idx >= len(self.pages):
|
|
return max(len(self.pages) - 1, 0)
|
|
return idx
|
|
|
|
def getIndexAbsolute(self, idx=0):
|
|
if idx < 0:
|
|
idx = max(len(self.pages) + idx, 0)
|
|
return idx
|
|
|