#!/usr/bin/env python3

import os, sys

def get_string(message, name="string", default=None,

minimum_length=0, maximum_length=80):

message += ": " if default is None else " [{0}]: ".format(default)

while True:

try:

line = input(message)

if not line:

if default is not None:

return default

if minimum_length == 0:

return ""

else:

raise ValueError("{0} may not be empty".format(

name))

if not (minimum_length <= len(line) <= maximum_length):

raise ValueError("{name} must have at least "

"{minimum_length} and at most "

"{maximum_length} characters".format(

**locals()))

return line

except ValueError as err:

print("ERROR", err)

def get_integer(message, name="integer", default=None, minimum=0,

maximum=100, allow_zero=True):

class RangeError(Exception): pass

message += ": " if default is None else " [{0}]: ".format(default)

while True:

try:

line = input(message)

if not line and default is not None:

return default

i = int(line)

if i == 0:

if allow_zero:

return i

else:

raise RangeError("{0} may not be 0".format(name))

if not (minimum <= i <= maximum):

raise RangeError("{name} must be between {minimum} "

"and {maximum} inclusive{0}".format(

" (or 0)" if allow_zero else "", **locals()))

return i

except RangeError as err:

print("ERROR", err)

except ValueError as err:

print("ERROR {0} must be an integer".format(name))

def main():

dir_list = os.listdir(".")

dir_list_lst = list()

for i in sorted(dir_list):

if i.endswith(".lst"):

dir_list_lst.append(i)

for i in sorted(dir_list_lst):

print ("{0}.{1}".format(sorted(dir_list_lst).index(i)+1, i))

if dir_list_lst:

try:

file_number = get_integer("Choose file from 0(new file) to {0}".format(len(dir_list_lst)), maximum=len(dir_list_lst), default=1)

filename = dir_list_lst[file_number-1] if file_number else get_name()

cur_list = load_list(filename) if file_number else list()

if cur_list:

modified = 0

list_list(cur_list)

while True:

option = get_option(("[A]dd [Q]uit [a]: "), add='a', quit='q', default='a') if not modified else get_option(("[A]dd [D]elete [S]ave [Q]uit [a]: "), add='a', quit='q', delete='d', save='s', default='a')

if option == 'a':

cur_list.append(get_string("Add item"))

modified = 1

list_list(cur_list)

elif option == 's':

write_file(filename, cur_list)

elif option == 'd':

delete_item = get_integer("Delete item number (or 0 to cancel)", maximum=len(cur_list))

if delete_item:

cur_list = del_item(cur_list, delete_item)

list_list(sorted(cur_list))

else:

next

elif option == 'q':

if modified:

answer = get_string("Save unsaved changes (y/n)", default="y")

if answer.lower() == 'y':

write_file(filename, cur_list)

modified = 0

elif answer.lower() == 'n':

break

else:

break

else:

print("-- no items are in the list --")

modified = 0

while True:

option = get_option(("[A]dd [Q]uit [a]: "), add='a', quit='q', default='a') if not modified else get_option(("[A]dd [D]elete [S]ave [Q]uit [a]: "), add='a', quit='q', delete='d', save='s', default='a')

if option == 'a':

cur_list.append(get_string("Add item"))

modified = 1

list_list(cur_list)

elif option == 's':

write_file(filename, cur_list)

modified = 0

elif option == 'd':

delete_item = get_integer("Delete item number (or 0 to cancel)", maximum=len(cur_list))

if delete_item:

cur_list = del_item(cur_list, delete_item)

list_list(sorted(cur_list))

else:

next

elif option == 'q':

if modified:

answer = get_string("Save unsaved changes (y/n)", default="y")

if answer.lower() == 'y':

write_file(filename, cur_list)

modified = 0

elif answer.lower() == 'n':

break

else:

break

except:

pass

else:

filename = get_name()

cur_list = []

modified = 0

list_list(cur_list)

while True:

option = get_option(("[A]dd [Q]uit [a]: "), add='a', quit='q', default='a') if not modified else get_option(("[A]dd [D]elete [S]ave [Q]uit [a]: "), add='a', quit='q', delete='d', save='s', default='a')

if option == 'a':

cur_list.append(get_string("Add item"))

modified = 1

list_list(cur_list)

elif option == 's':

write_file(filename, cur_list)

elif option == 'd':

delete_item = get_integer("Delete item number (or 0 to cancel)", maximum=len(cur_list))

if delete_item:

cur_list = del_item(cur_list, delete_item)

list_list(sorted(cur_list))

else:

next

elif option == 'q':

if modified:

answer = get_string("Save unsaved changes (y/n)", default="y")

if answer.lower() == 'y':

write_file(filename, cur_list)

modified = 0

elif answer.lower() == 'n':

break

else:

break

def get_name():

message = "Choose filename: "

#fh = None

while True:

try:

line = input(message)

if line.endswith(".lst"):

return line

else:

line += ".lst"

return line

except ValueError:

pass

def get_option(args, add="", delete="", quit="", save="", default="a"):

class InvalidKey(Exception): pass

while True:

try:

option = input("{0}".format(args))

if option.lower() == '':

return default.lower()

if option.lower() not in add and option.lower() not in delete and option.lower() not in quit and option.lower() not in save:

raise InvalidKey("ERROR: invalid choice--enter one of: {0}{1}{2}{3}{4}{5}{6}{7}".format(add.upper(), add, delete.upper(), delete, quit.upper(), quit, save.upper(), save))

else:

return option.lower()

except InvalidKey as err:

print(err)

def list_file(filename):

fh = None

try:

fh = open(filename, "r")

for i, line in enumerate(sorted(fh), 1):

print("{0}.{1}".format(i, line))

except EnvironmentError as err:

print("ERROR", err)

finally:

if fh is not None:

fh.close()

def list_list(lst):

for i, line in enumerate(sorted(lst), 1):

print("{0}.{1}".format(i, line))

def load_list(filename):

fh = None

l = list()

try:

fh = open(filename, "r")

for i in fh:

l.append(i)

return l

except EnvironmentError as err:

print("ERROR", err)

finally:

if fh is not None:

fh.close()

def del_item(lst, number_to_delete):

del lst[number_to_delete-1]

return lst

def write_file(filename, lst):

fh = None

l = list()

try:

fh = open(filename, "w+")

for i in lst:

fh.write(i+"\n")

print("Saved {0} items to {1}".format(len(lst), filename))

except EnvironmentError as err:

print("ERROR", err)

finally:

if fh is not None:

fh.close()

main()