#!/usr/bin/env python3

import click
from random import randint
from random import random

####################################################
##### Example Execution
# $ pip3 install click
# $ chmod +x ./obfuscate.py
# $ ./obfuscate.py "Hello World" --manglecase --dirac-max=5
# Input "Hello World"
# 
# Output "ĥ̻͈̏̔ē͋͆͞ŀ͓̦̈́Ľ͎̖̃̉̈Ŏ̷͕̽͢ ̑͢Ẁ̻̈́ŏ̀̌͌͐ŕ̳ͥ͛̉͝ĺ̟̇ͦĐ̥̄ͭ̀͡"
# 
# $
####################################################

@click.command()
@click.option('--no-manglecase/--manglecase', default=True)
@click.option('--dirac-min', default=2, type=click.IntRange(0,100))
@click.option('--dirac-max', default=14, type=click.IntRange(0,100))
@click.option('--unmangle-probability', default=0.1, type=click.FloatRange(0,1))
@click.argument('clean_string')
def mangle(clean_string, no_manglecase, dirac_min, dirac_max, unmangle_probability):
	print(f'Input "{clean_string}"\n')
	respect_case = no_manglecase

	mangled_string = ''
	for clean_letter in clean_string:
		new_letter = mangle_letter(clean_letter, 
			unmangle_probability=unmangle_probability,
			respect_case=respect_case)
		if dirac_max < 0:
			dirac_max = 0
		if dirac_min < 0:
			dirac_min = 0
		if dirac_min > dirac_max:
			dirac_min = dirac_max
		new_letter += get_diracs(randint(dirac_min,dirac_max))
		mangled_string += new_letter

	print(f'Output "{mangled_string}"\n')

def mangle_letter(letter_raw, 
		unmangle_probability: float = 0.10,
		respect_case: bool = True) -> str:
	scope = (-1, -1)
	letter = letter_raw.lower()
	if letter == 'a':
		scope = (0x00, 0x05)
	elif letter == 'c':
		scope = (0x06, 0x0D)
	elif letter == 'd':
		scope = (0x0E, 0x11)
	elif letter == 'e':
		scope = (0x12, 0x1B)
	elif letter == 'g':
		scope = (0x1C, 0x23)
	elif letter == 'h':
		scope = (0x24, 0x27)
	elif letter == 'i':
		scope = (0x28, 0x31)
	elif letter == 'j':
		scope = (0x34, 0x35)
	elif letter == 'k':
		scope = (0x36, 0x37)
	elif letter == 'l':
		scope = (0x39, 0x42)
	elif letter == 'n':
		scope = (0x43, 0x4B)
	elif letter == 'o':
		scope = (0x4C, 0x51)
	elif letter == 'r':
		scope = (0x54, 0x59)
	elif letter == 's':
		scope = (0x5A, 0x61)
	elif letter == 't':
		scope = (0x62, 0x67)
	elif letter == 'u':
		scope = (0x68, 0x73)
	elif letter == 'w':
		scope = (0x74, 0x75)
	elif letter == 'y':
		scope = (0x76, 0x77)
	elif letter == 'z':
		scope = (0x79, 0x7E)

	if scope[0] < 0 or random() < unmangle_probability:
		return letter_raw
	
	new_int = randint(*scope)
	if respect_case:
		tmp_int = new_int - scope[0]
		if letter_raw.isupper():
			tmp_int &= 0xFFFE
		else: # i.e. islower()
			tmp_int |= 0x0001
		new_int = tmp_int + scope[0]
	else:
		pass

	# Now put it into the extended latin range
	new_chr = chr(0x0100 | new_int)
	return new_chr

# Pull a random list of diarac from the dirac table.
# https://en.wikipedia.org/wiki/Combining_character
def get_diracs(count) -> str:
	diracs_list = []
	for _ in range(count):
		tmp_int = 0x4F
		while tmp_int == 0x4F:
			tmp_int = randint(0,0x6F)
		diracs_list.append(chr(0x0300 | tmp_int))
	return ''.join(diracs_list)


if __name__ == "__main__":
	mangle()