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- '''
- Copyright (C) 2007 Martin Owens
-
- 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
- '''
-
- import itertools
- import sys
- from lxml import etree
-
- class Barcode:
- def __init__(self, param={}):
- self.document = None
- self.x = 0
- self.y = 0
-
- if param.has_key('document'):
- self.document = param['document']
- if param.has_key('x'):
- self.x = param['x']
- if param.has_key('y'):
- self.y = param['y']
-
- if param.has_key('height'):
- self.height = param['height']
- else:
- self.height = 30
-
- self.text = param['text']
- self.label = self.text
- self.string = self.encode( self.text )
- if not self.string:
- return
- self.width = len(self.string)
- self.data = self.graphicalArray(self.string)
-
- def generate(self):
- svg_uri = u'http://www.w3.org/2000/svg'
- if not self.string or not self.data:
- return
-
- data = self.data;
-
- # create an SVG document if required
- # if not self.document:
- # self.document = UNKNOWN
-
- if not self.document:
- sys.stderr.write("No document defined to add barcode to\n")
- return
-
- # Collect document ids
- doc_ids = {}
- docIdNodes = self.document.xpath('//@id')
- for m in docIdNodes:
- doc_ids[m] = 1
-
- # We don't have svg documents so lets do something raw:
- name = 'barcode'
-
- # Make sure that the id/name is inique
- index = 0
- while (doc_ids.has_key(name)):
- name = 'barcode' + str(index)
- index = index + 1
-
- # use an svg group element to contain the barcode
- barcode = etree.Element('{%s}%s' % (svg_uri,'g'))
- barcode.set('id', name)
- barcode.set('style', 'fill: black;')
-
- draw = 1
- wOffset = int(self.x)
- id = 1
-
- for datum in data:
- # Datum 0 tells us what style of bar is to come next
- style = self.getStyle(int(datum[0]))
- # Datum 1 tells us what width in units,
- # style tells us how wide a unit is
- width = int(datum[1]) * int(style['width'])
-
- if style['write']:
- # Add height for styles such as EA8 where
- # the barcode goes into the text
-
- rect = etree.SubElement(barcode,'{%s}%s' % (svg_uri,'rect'))
- rect.set('x', str(wOffset))
- rect.set('y', str(style['top']))
- rect.set('width', str(width))
- rect.set('height', str(style['height']))
- rect.set('id', name + '_bar' + str(id))
- wOffset = int(wOffset) + int(width)
- id = id + 1
-
- barwidth = wOffset - int(self.x)
- # Add text at the bottom of the barcode
- text = etree.SubElement(barcode,'{%s}%s' % (svg_uri,'text'))
- text.set( 'x', str(int(self.x) + int(barwidth / 2)) )
- text.set( 'y', str(int(self.height) + 10 + int(self.y)) )
- text.set( 'style', 'font-size:' + self.fontSize() + 'px;text-align:center;text-anchor:middle;' )
- text.set( '{http://www.w3.org/XML/1998/namespace}space', 'preserve' )
- text.set( 'id', name + '_bottomtext' )
-
- text.text = str(self.label)
-
- return barcode
-
- # Converts black and white markers into a space array
- def graphicalArray(self, code):
- return [(x,len(list(y))) for x, y in itertools.groupby(code)]
-
- def getStyle(self, index):
- result = { 'width' : 1, 'top' : int(self.y), 'write' : False }
- if index==1: # Black Bar
- result['height'] = int(self.height)
- result['write'] = True
- return result
-
- def fontSize(self):
- return '9'
-