paperless-asn-qr-codes/paperless_asn_qr_codes/avery_labels.py

import os
from collections.abc import Iterator
from reportlab.pdfgen import canvas
from reportlab.lib.pagesizes import LETTER, A4
from reportlab.lib.units import inch
from reportlab.pdfbase import pdfmetrics
from reportlab.pdfbase.ttfonts import TTFont
from reportlab.lib.units import mm

# Usage:
#   label = AveryLabels.AveryLabel(5160)
#   label.open( "labels5160.pdf" )
#   label.render( RenderAddress, 30 )
#   label.close()
#
# 'render' can either pass a callable, which receives the canvas object
# (with X,Y=0,0 at the lower right) or a string "form" name of a form
# previously created with canv.beginForm().


# labels across
# labels down
# label size w/h
# label gutter across/down
# page margins left/top
# page size

labelInfo = {
    "averyL4731": ( 7, 27, (25.4*mm, 10*mm), (2.5*mm, 0), (9*mm, 13.5*mm), A4),
    # 2.6 x 1 address labels
    "avery5160": ( 3, 10, (187,  72), (11, 0), (14, 36), LETTER),
    "avery5161": ( 2, 10, (288,  72), (0, 0), (18, 36), LETTER),
    # 4 x 2 address labels
    "avery5163": ( 2,  5, (288, 144), (0, 0), (18, 36), LETTER),
    # 1.75 x 0.5 return address labels
    "avery5167": ( 4, 20, (126,  36), (0, 0), (54, 36), LETTER),
    # 3.5 x 2 business cards
    "avery5371": ( 2,  5, (252, 144), (0, 0), (54, 36), LETTER),
}

RETURN_ADDRESS = 5167
BUSINESS_CARDS = 5371

class AveryLabel:

    def __init__(self, label, **kwargs):
        data = labelInfo[label]
        self.across = data[0]
        self.down = data[1]
        self.size = data[2]
        self.labelsep = self.size[0]+data[3][0], self.size[1]+data[3][1]
        self.margins = data[4]
        self.topDown = True
        self.debug = False
        self.pagesize = data[5]
        self.position = 0
        self.__dict__.update(kwargs)

    def open(self, filename):
        self.canvas = canvas.Canvas( filename, pagesize=self.pagesize )
        if self.debug:
            self.canvas.setPageCompression( 0 )
        self.canvas.setLineJoin(1)
        self.canvas.setLineCap(1)

    def topLeft(self, x=None, y=None):
        if x == None:
            x = self.position
        if y == None:
            if self.topDown:
                x,y = divmod(x, self.down)
            else:
                y,x = divmod(x, self.across)

        return (
            self.margins[0]+x*self.labelsep[0],
            self.pagesize[1] - self.margins[1] - (y+1)*self.labelsep[1]
        )

    def advance(self):
        self.position += 1
        if self.position == self.across * self.down:
            self.canvas.showPage()
            self.position = 0

    def close(self):
        if self.position:
            self.canvas.showPage()
        self.canvas.save()
        self.canvas = None

    # To render, you can either create a template and tell me
    # "go draw N of these templates" or provide a callback.
    # Callback receives canvas, width, height.
    #
    # Or, pass a callable and an iterator.  We'll do one label
    # per iteration of the iterator.

    def render( self, thing, count, *args ):
        assert callable(thing) or isinstance(thing, str)
        if isinstance(count, Iterator):
            return self.render_iterator( thing, count )

        canv = self.canvas
        for i in range(count):
            canv.saveState()
            canv.translate( *self.topLeft() )
            if self.debug:
                canv.setLineWidth( 0.25 )
                canv.rect( 0, 0, self.size[0], self.size[1] )
            if callable(thing):
                thing( canv, self.size[0], self.size[1], *args )
            elif isinstance(thing, str):
                canv.doForm(thing)
            canv.restoreState()
            self.advance()

    def render_iterator( self, func, iterator ):
        canv = self.canvas
        for chunk in iterator:
            canv.saveState()
            canv.translate( *self.topLeft() )
            if self.debug:
                canv.setLineWidth( 0.25 )
                canv.rect( 0, 0, self.size[0], self.size[1] )
            func( canv, self.size[0], self.size[1], chunk )
            canv.restoreState()
            self.advance()