0.3a1

-----

-  Refactored to rely on `edbob <http://edbob.org/>`_.  (Most of Rattail's

   "guts" now live there instead.)

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                       Version 3, 19 November 2007

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include *.txt

Rattail

=======

Rattail is a retail software framework based on `edbob <http://edbob.org/>`_,

and released under the GNU Affero General Public License.

This is the core ``rattail`` package.

Please see Rattail's `home page <http://rattail.edbob.org/>`_ for more

information.

Installation

------------

Install the software with::

   $ pip install rattail

Usage

-----

Built-in help can be seen with::

   $ rattail help

#!/usr/bin/env python

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

################################################################################

#

#  Rattail -- Retail Software Framework

#  Copyright © 2010-2012 Lance Edgar

#

#  This file is part of Rattail.

#

#  Rattail is free software: you can redistribute it and/or modify it under the

#  terms of the GNU Affero General Public License as published by the Free

#  Software Foundation, either version 3 of the License, or (at your option)

#  any later version.

#

#  Rattail 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 Affero General Public License for

#  more details.

#

#  You should have received a copy of the GNU Affero General Public License

#  along with Rattail.  If not, see <http://www.gnu.org/licenses/>.

#

################################################################################

"""

``rattail`` -- Namespace Root

"""

from pkgutil import extend_path

__path__ = extend_path(__path__, __name__)

from edbob.db.extensions import Extension

import rattail.model

from rattail._version import __version__

from rattail.enum import *

from rattail.model import *

__all__ = rattail.model.__all__

class RattailExtension(Extension):

    name = 'rattail'

__version__ = '0.3a1'

#!/usr/bin/env python

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

################################################################################

#

#  Rattail -- Retail Software Framework

#  Copyright © 2010-2012 Lance Edgar

#

#  This file is part of Rattail.

#

#  Rattail is free software: you can redistribute it and/or modify it under the

#  terms of the GNU Affero General Public License as published by the Free

#  Software Foundation, either version 3 of the License, or (at your option)

#  any later version.

#

#  Rattail 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 Affero General Public License for

#  more details.

#

#  You should have received a copy of the GNU Affero General Public License

#  along with Rattail.  If not, see <http://www.gnu.org/licenses/>.

#

################################################################################

"""

``rattail.barcodes`` -- Barcode Utilities

"""

# import re

def upc_check_digit(data):

    """

    Calculates the check digit for ``data``, according to the standard

    `UPC algorithm <http://en.wikipedia.org/wiki/Check_digit#UPC>`_.  The check

    digit will be returned in integer form.

    """

    sum_ = 0

    for i in range(len(data) - 1, -1, -2):

        sum_ += int(data[i]) * 3

    for i in range(len(data) - 2, -1, -2):

        sum_ += int(data[i])

    remainder = sum_ % 10

    if remainder == 0:

        return 0

    return 10 - remainder

def luhn_check_digit(data):

    """

    Calculate the check digit for ``data`` according to the

    `Luhn algorithm <http://en.wikipedia.org/wiki/Luhn_algorithm>`_.  The check

    digit will be returned in integer form.

    """

    reverse_data = ''.join([x for x in reversed(data)])

    sum_ = 0

    for i in range(len(reverse_data)):

        digit = int(reverse_data[i])

        if i % 2 == 0:

            digit *= 2

            digit = sum([int(x) for x in str(digit)])

        sum_ += digit

    remainder = sum_ % 10

    if remainder == 0:

        return 0

    return 10 - remainder

def price_check_digit(data):

    """

    Returns the "price check digit" for ``data``, which must be a

    four-character string of digits.  The check digit is returned in integer

    form.

    This typically would be used to validate a random weight UPC.  See GS1's

    `Price Check Digit (North American POS Product Sold by Weight/Measure)

    <http://www.gs1us.org/GS1%20US%20BarCodes%20and%20eCom%20-%20The%20Global%20Language%20of%20Business.htm#PCD>`_

    for more information.

    """

    if not isinstance(data, basestring) and len(data) == 4:

        raise ValueError("'data' must be 4-character string; got: %s" % str(data))

    map1 = {0:0, 1:2, 2:4, 3:6, 4:8, 5:9, 6:1, 7:3, 8:5, 9:7}

    map2 = {0:0, 1:3, 2:6, 3:9, 4:2, 5:5, 6:8, 7:1, 8:4, 9:7}

    map3 = {0:0, 1:5, 2:9, 3:4, 4:8, 5:3, 6:7, 7:2, 8:6, 9:1}

    data = [int(x) for x in data]

    sum_ = map1[data[0]] + map1[data[1]] + map2[data[2]] + map3[data[3]]

    return int(str(3 * sum_)[-1])

def upce_to_upca(upce, include_check_digit=False):

    """

    Expands ``upce`` (which is assumed to be a valid UPC-E barcode) into its

    full UPC-A equivalent.  The return value will have either 11 or 12 digits,

    depending on ``include_check_digit``.

    """

    if len(upce) == 8:

        upce = upce[1:7]