#!/usr/bin/env python
######################################################
# Removes or adds line numbers from a .txt file
# Leave newName as None to write to the .txt file
#
# Written by Sunjay Varma
# Check out www.sunjay-varma.com for more cool stuff
######################################################

DEFAULT_PREFIX = ". "

import sys

## Adds line numbers to the contents of a .txt file.
def addLNumbers(filename, newName=None, widthIndex=None, prefix=None):
  # first open the filename
  f = open(filename, 'r')

  # fix up the widthIndex
  widthIndex = widthIndex or 3

  # fix up the prefix
  prefix = prefix or DEFAULT_PREFIX

  # The list where the newly formatted lines will go.
  nlines = []

  # The number to add to the line.
  num = 1

  # go through the lines in the .txt file
  for line in f.readlines():
    # add a formatted line to nlines
    nlines.append(("%"+("."+str(widthIndex)+"i"))%num + prefix + line)
    # incrment num
    num += 1

  # close the file
  f.close()
  
  # get the new file name
  newName = newName or filename

  # write the new lines
  newfile = open(newName, 'w')
  newfile.write(''.join(nlines))
  newfile.close()

# Removes line numbers from a the contents of a .txt file.
def removeLNumbers(filename, newName=None, prefix=None):
  # first open the filename
  f = open(filename, 'r')

  # fix up the prefix
  prefix = prefix or DEFAULT_PREFIX
  
  # a list of the tranfered lines.
  nlines = []

  # go through all the lines
  for line in f.readlines():
    # fix the line
    try: nlines.append(line[line.index(prefix)+1:])
    except: continue # line must not have the prefix...

  # close the file
  f.close()

  # get the new file name
  newName = newName or filename

  # write the new lines
  newfile = open(newName, 'w')
  newfile.write(''.join(nlines))
  newfile.close()



if __name__ == '__main__':
  if raw_input("Type add if you want to add line numbers and remove if you want to remove them:\n\t").lower().startswith('add'):
    # get the file name
    fname = raw_input("Enter the complete file path of the file you want to convert:\n\t")
    if raw_input("Would you like to write to a new file? ").lower().startswith('y'):
      nname = raw_input("Please enter the new file path. ")

    else: nname=None

    if raw_input("Is there a specific prefix you want after each line number? ").lower().startswith('y'):
      prefix = str(raw_input("Please enter the prefix: "))

    else: prefix = None

    if raw_input("Is there a maximum amount of 0s you would like to use? ").lower().startswith('y'):
      index = input("Please enter the max width before each line number:\n\t")

    else:
      index = None

    still_running = 1
    
    try: addLNumbers(fname, nname, index, prefix)
    except:
      still_running = 0
      for item in sys.exc_info(): print item
      raw_input("Press Enter to exit.")

    if still_running:
      print ""
      print "Your file has had line numbers added to it sucessfully."
      print "New File Location: ", nname or fname
      print "WidthIndex: ", index or "3 (Default)"
      print "The prefix used: \""+(prefix or DEFAULT_PREFIX)+"\""
      print ""
      print "Thank you for using LineNumConverter.py"
      print "Check out www.sunjay-varma.com for more stuff."
      print ""
      print "Bye Bye!"
      raw_input("Press Enter to exit")
    
  else:
    # get the file name
    fname = raw_input("Enter the complete file path of the file you want to convert:\n\t")
    if raw_input("Would you like to write to a new file? ").lower().startswith('y'):
      nname = raw_input("Please enter the new file path. ")

    else: nname=None

    if raw_input("Is there a specific prefix after each line number? ").lower().startswith('y'):
      prefix = raw_input("Please enter the prefix: ")

    else: prefix = None

    still_running = 1

    try: removeLNumbers(fname, nname, prefix)
    except:
      still_running = 0
      for item in sys.exc_info(): print item
      raw_input("Press Enter to exit.")

    if still_running:
      print ""
      print "Your file has been sucessfully cleaned of line numbers."
      print "New File Location: ", nname or fname
      print "The prefix used: \""+(prefix or DEFAULT_PREFIX)+"\""
      print ""
      print "Thank you for using LineNumConverter.py"
      print "Check out www.sunjay-varma.com for more stuff."
      print ""
      print "Bye Bye!"
      raw_input("Press Enter to exit")