Add tap/knock language

README.md

@@ -288,6 +288,7 @@ o
 - [X] `southpark`: converts letters to Kenny's language from Southpark (whitespace is also handled)
 - [X] `southpark-icase`: case insensitive variant of `southpark`
 - [X] `tomtom`: similar to `morse`, using slashes and backslashes
+- [X] `tap` : converts tap/knock code commonly used by prisoners
 
 #### Others
 

codext/languages/__init__.py

@@ -7,4 +7,5 @@
 from .radio import *
 from .southpark import *
 from .tomtom import *
+from .tap import *
 

codext/languages/tap.py

@@ -0,0 +1,56 @@
+# -*- coding: UTF-8 -*-
+"""Tap code - Tap/knock code encoding.
+
+This codec:
+- en/decodes strings from str to str
+- en/decodes strings from bytes to bytes
+- decodes file content to str (read)
+- encodes file content from str to bytes (write)
+"""
+from ..__common__ import *
+
+
+__examples__ = {
+    'enc(tap)': {'this is a test' : '.... ....  .. ...  .. ....  .... ...  .. ....  .... ...  . .  .... ....  . .....  .... ...  .... ....'},
+    'dec(tap)': {'.... ....  .. ...  .. ....  .... ...  .. ....  .... ...  . .  .... ....  . .....  .... ...  .... ....' : 'thisisatest'}
+}
+
+
+def build_encmap(map) : 
+    dict = {}
+    i = 0
+    for col in range(1,6) : 
+        for row in range(1,6) : 
+            dict[map[i]] = "" + col * "." + " " + row * "."
+            i += 1
+    dict['k'] = dict['c']
+    return dict
+
+def encode_tap(text, errors = 'strict') : 
+    map = 'abcdefghijlmnopqrstuvwxyz'
+    ENCMAP = build_encmap(map)
+    encoded = ""
+    for i, letter in enumerate(text) :
+        try : 
+            encoded += ENCMAP[letter.lower()]
+        except KeyError : 
+            pass
+        if i != len(text) - 1 and letter != ' ': 
+            encoded += '  '
+    return encoded, len(text)    
+
+
+def decode_tap(text, errors = 'ignore') : 
+    map = 'abcdefghijlmnopqrstuvwxyz'
+    ENCMAP = build_encmap(map)
+    decoded = ""
+    for elem in text.split("  ") :
+        try : 
+            decoded += next(key for key, value in ENCMAP.items() if value == elem)
+        except StopIteration : 
+            print("Invalid character(s) in the input. This is what could be decoded :")
+    return decoded, len(text)    
+
+
+add("tap", encode_tap, decode_tap, ignore_case="both")
+

docs/enc/languages.md

@@ -164,3 +164,19 @@ This codec is similar to morse. It converts text into slashes and backslashes.
 'THIS IS A TEST'
 ```
 
+-----
+
+### Tap
+
+Converts tap/knock code [commonly used by prisoners](https://en.wikipedia.org/wiki/Tap_code). Uses 25 letters, 'k' codes as 'c'.  
+
+**Codec** | **Conversions** | **Aliases** | **Comment**
+:---: | :---: | --- | ---
+`tap` | text <-> tap/knock encoded text | `tap` | uses '&nbsp; &nbsp;' (double space) as a separator for letters. No spaces between words after decoding. 
+
+```python
+>>> codext.encode("this is a test", "tap")
+'.... ....  .. ...  .. ....  .... ...  .. ....  .... ...  . .  .... ....  . .....  .... ...  .... ....'
+>>> codext.decode(".... ....  .. ...  .. ....  .... ...  .. ....  .... ...  . .  .... ....  . .....  .... ...  .... ....", "tap")
+'thisisatest'
+```