1 files changed, 187 insertions, 0 deletions
diff --git a/share/extensions/barcode/Code93.py b/share/extensions/barcode/Code93.py
new file mode 100644
index 0000000..1417b3e
--- /dev/null
+++ b/share/extensions/barcode/Code93.py
@@ -0,0 +1,187 @@
+# coding=utf-8
+#
+# 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA.
+#
+"""
+Python barcode renderer for Code93 barcodes. Designed for use with Inkscape.
+"""
+
+from .Base import Barcode
+
+PALLET = list("0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ-. $/+%")
+PALLET.append("($)")
+PALLET.append("(/)")
+PALLET.append("(+)")
+PALLET.append("(%)")
+PALLET.append("MARKER")
+
+MAP = dict((PALLET[i], i) for i in range(len(PALLET)))
+
+
+def get_map(array):
+    """Extended ENCODE maps for full ASCII Code93"""
+    result = {}
+    pos = 10
+    for char in array:
+        result[chr(char)] = PALLET[pos]
+        pos += 1
+    return result
+
+
+# MapA is eclectic, but B, C, D are all ASCII ranges
+MAP_A = get_map(
+    [
+        27,
+        28,
+        29,
+        30,
+        31,
+        59,
+        60,
+        61,
+        62,
+        63,
+        91,
+        92,
+        93,
+        94,
+        95,
+        123,
+        124,
+        125,
+        126,
+        127,
+        0,
+        64,
+        96,
+        127,
+        127,
+        127,
+    ]
+)  # %
+MAP_B = get_map(range(1, 26))  # $
+MAP_C = get_map(range(33, 58))  # /
+MAP_D = get_map(range(97, 122))  # +
+
+ENCODE = [
+    "100010100",
+    "101001000",
+    "101000100",
+    "101000010",
+    "100101000",
+    "100100100",
+    "100100010",
+    "101010000",
+    "100010010",
+    "100001010",
+    "110101000",
+    "110100100",
+    "110100010",
+    "110010100",
+    "110010010",
+    "110001010",
+    "101101000",
+    "101100100",
+    "101100010",
+    "100110100",
+    "100011010",
+    "101011000",
+    "101001100",
+    "101000110",
+    "100101100",
+    "100010110",
+    "110110100",
+    "110110010",
+    "110101100",
+    "110100110",
+    "110010110",
+    "110011010",
+    "101101100",
+    "101100110",
+    "100110110",
+    "100111010",
+    "100101110",
+    "111010100",
+    "111010010",
+    "111001010",
+    "101101110",
+    "101110110",
+    "110101110",
+    "100100110",
+    "111011010",
+    "111010110",
+    "100110010",
+    "101011110",
+    "",
+]
+
+
+class Code93(Barcode):
+    """Encode Code93 Barcode"""
+
+    def encode(self, text):
+        # start marker
+        bits = ENCODE[MAP.get("MARKER", -1)]
+
+        # Extend to ASCII charset ( return Array )
+        text = Code93.encode_ascii(text)
+
+        # Calculate the checksums
+        text.append(Code93.checksum(text, 20))  # C
+        text.append(Code93.checksum(text, 15))  # K
+
+        # Now convert text into the ENCODE bits (black and white stripes)
+        for char in text:
+            bits = bits + ENCODE[MAP.get(char, -1)]
+
+        # end marker and termination bar
+        return bits + ENCODE[MAP.get("MARKER", -1)] + "1"
+
+    @staticmethod
+    def checksum(text, mod):
+        """Generate a code 93 checksum"""
+        weight = len(text) % mod
+        check = 0
+        for char in text:
+            check = check + (MAP[char] * weight)
+            # Reset the weight is required
+            weight -= 1
+            if weight == 0:
+                weight = mod
+
+        return PALLET[check % 47]
+
+    @staticmethod
+    def encode_ascii(text):
+        """Some characters need re-ENCODE into the code93 specification"""
+        result = []
+        for char in text:
+            if char in MAP:
+                result.append(char)
+            elif char in MAP_A:
+                result.append("(%)")
+                result.append(MAP_A[char])
+            elif char in MAP_B:
+                result.append("($)")
+                result.append(MAP_B[char])
+            elif char in MAP_C:
+                result.append("(/)")
+                result.append(MAP_C[char])
+            elif char in MAP_D:
+                result.append("(+)")
+                result.append(MAP_D[char])
+        return result