Iniital commit

barcode_gen.py

@@ -0,0 +1,120 @@
+#!/usr/bin/env python3
+
+import math
+import itertools
+import textwrap
+
+import click
+from reedmuller import reedmuller
+
+
+class Tag:
+    """ Helper class to ease creation of SVG. All API functions that create SVG allow you to substitute this with your
+    own implementation by passing a ``tag`` parameter. """
+
+    def __init__(self, name, children=None, root=False, **attrs):
+        if (fill := attrs.get('fill')) and isinstance(fill, tuple):
+            attrs['fill'], attrs['fill-opacity'] = fill
+        if (stroke := attrs.get('stroke')) and isinstance(stroke, tuple):
+            attrs['stroke'], attrs['stroke-opacity'] = stroke
+        self.name, self.attrs = name, attrs
+        self.children = children or []
+        self.root = root
+
+    def __str__(self):
+        prefix = '<?xml version="1.0" encoding="utf-8"?>\n' if self.root else ''
+        opening = ' '.join([self.name] + [f'{key.replace("__", ":").replace("_", "-")}="{value}"' for key, value in self.attrs.items()])
+        if self.children:
+            children = '\n'.join(textwrap.indent(str(c), '  ') for c in self.children)
+            return f'{prefix}<{opening}>\n{children}\n</{self.name}>'
+        else:
+            return f'{prefix}<{opening}/>'
+
+
+    @classmethod
+    def setup_svg(kls, tags, bounds, margin=0, unit='mm', pagecolor='white', inkscape=False):
+        (min_x, min_y), (max_x, max_y) = bounds
+
+        if margin:
+            min_x -= margin
+            min_y -= margin
+            max_x += margin
+            max_y += margin
+
+        w, h = max_x - min_x, max_y - min_y
+        w = 1.0 if math.isclose(w, 0.0) else w
+        h = 1.0 if math.isclose(h, 0.0) else h
+
+        if inkscape:
+            tags.insert(0, kls('sodipodi:namedview', [], id='namedview1', pagecolor=pagecolor,
+                    inkscape__document_units=unit))
+            namespaces = dict(
+                xmlns="http://www.w3.org/2000/svg",
+                xmlns__xlink="http://www.w3.org/1999/xlink",
+                xmlns__sodipodi='http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd',
+                xmlns__inkscape='http://www.inkscape.org/namespaces/inkscape')
+
+        else:
+            namespaces = dict(
+                xmlns="http://www.w3.org/2000/svg",
+                xmlns__xlink="http://www.w3.org/1999/xlink")
+
+        return kls('svg', tags,
+                width=f'{w}{unit}', height=f'{h}{unit}',
+                viewBox=f'{min_x} {min_y} {w} {h}',
+                style=f'background-color:{pagecolor}',
+                **namespaces,
+                root=True)
+
+
+@click.command()
+@click.option('-h', '--height', type=float, default=20, help='Bar height in mm')
+@click.option('-t/-n', '--text/--no-text', default=True, help='Whether to add text containing the data under the bar code')
+@click.option('-f', '--font', default='sans-serif', help='Font for the text underneath the bar code')
+@click.option('-s', '--font-size', type=float, default=10, help='Font size for the text underneath the bar code in points (pt)')
+@click.option('-b', '--bar-width', type=float, default=1.0, help='Bar width in mm')
+@click.option('-m', '--margin', type=float, default=2.0, help='Margin around bar code in mm')
+@click.option('-c', '--color', default='black', help='SVG color for the bar code')
+@click.option('--text-color', default=None, help='SVG color for the text (defaults to the bar code\'s color)')
+@click.option('--dpi', type=float, default=96, help='DPI value to assume for internal SVG unit conversions')
+@click.argument('data')
+@click.argument('outfile', type=click.File('w'), default='-')
+def cli(data, outfile, height, text, font, font_size, bar_width, margin, color, text_color, dpi):
+    data = int(data, 16)
+    text_color = text_color or color
+
+    NUM_BITS = 26
+
+    data_bits = [bool(data & (1<<i)) for i in range(NUM_BITS)]
+    data_encoded = itertools.chain(*[
+        (a, not a) for a in data_bits
+        ])
+    data_encoded = [True, False, True, False, *data_encoded, False, True, True, False, True]
+
+    bars = 32/2*3 + 2
+    width = bars * bar_width
+    # 1 px = 0.75 pt
+    pt_to_mm = lambda pt: pt / 0.75 /dpi * 25.4
+    font_size = pt_to_mm(font_size)
+    total_height = height + font_size*2
+
+    tags = []
+    for key, group in itertools.groupby(enumerate(data_encoded), key=lambda x: x[1]):
+        if key:
+            group = list(group)
+            x0, _key = group[0]
+            w = len(group)
+            tags.append(Tag('path', stroke=color, stroke_width=w, d=f'M {(x0 + w/2)*bar_width} 0 l 0 {height}'))
+    
+    if text:
+        tags.append(Tag('text', children=[f'{data:07x}'],
+                        x=width/2, y=height + 0.5*font_size,
+                        font_family=font, font_size=f'{font_size:.3f}px',
+                        text_anchor='middle', dominant_baseline='hanging',
+                        fill=text_color))
+
+    outfile.write(str(Tag.setup_svg(tags, bounds=((0, 0), (width, total_height)), margin=margin)))
+
+
+if __name__ == '__main__':
+    cli()