def _process_progressive(text, key, method, _reverse=False):
"""
(De)cypher message to progressive caesar (increasing offset).
"""
base = ord('A')
modulo = ord('Z') - base + 1
if method == PROGRESS_GEOMETRIC:
# Basic is a specific case of geometric, with key = 1!
delta = key
elif method == PROGRESS_SHIFT:
delta = key
key = 1
if _reverse:
s = -1
else:
s = 1
if ' ' in text:
ret = []
for w in text.split():
ret.append("".join(utils.char_shift(c, base, modulo, delta * s)
for c in w))
delta = (delta + key) % modulo
return " ".join(ret)
else: # Mono-word...
ret = []
for c in text:
ret.append(utils.char_shift(c, base, modulo, delta * s))
delta = (delta + key) % modulo
return "".join(ret)
def _process_progressive(text, key, method, _reverse=False):
"""
(De)cypher message to progressive caesar (increasing offset).
"""
base = ord('A')
modulo = ord('Z') - base + 1
if method == PROGRESS_GEOMETRIC:
# Basic is a specific case of geometric, with key = 1!
delta = key
elif method == PROGRESS_SHIFT:
delta = key
key = 1
if _reverse:
s = -1
else:
s = 1
if ' ' in text:
ret = []
for w in text.split():
ret.append("".join(
utils.char_shift(c, base, modulo, delta * s) for c in w))
delta = (delta + key) % modulo
return " ".join(ret)
else: # Mono-word...
ret = []
for c in text:
ret.append(utils.char_shift(c, base, modulo, delta * s))
delta = (delta + key) % modulo
return "".join(ret)
def do_cypher_basic(text, key):
"""
Cypher message to basic caesar (constant offset).
"""
# Let’s use a dict here (as it’s a constant one to one mapping).
base = ord('A')
modulo = ord('Z') - base + 1
_map = {c: utils.char_shift(c, base, modulo, key) for c in set(text)}
_map[' '] = ' '
return "".join(_map[c] for c in text)
def do_cypher_basic(text, key):
"""
Cypher message to basic caesar (constant offset).
"""
# Let’s use a dict here (as it’s a constant one to one mapping).
base = ord('A')
modulo = ord('Z') - base + 1
_map = {c: utils.char_shift(c, base, modulo, key) for c in set(text)}
_map[' '] = ' '
return "".join(_map[c] for c in text)
