evidence of me fixing dave's code

readcue.py

#!/usr/bin/env python3

#############################################################################
## readcue.py
## This file is part of readcue
## Copyright (C) 2014 Dhaval Anjaria
## Copyright (C) 2014 Darcy Bras da Silva
##
## This program is free software: you can redistribute it and/or modify
## it under the terms of the GNU General Public License as published by
## the Free Software Foundation, either version 3 of the License, or
## (at your option) any later version.
##
## This program is distributed in the hope that it will be useful,
## but WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
## GNU General Public License for more details.
##
## You should have received a copy of the GNU General Public License
## along with this program.  If not, see <http://www.gnu.org/licenses/
#############################################################################
## this script reads the cue file from a folder, reads the name of the
## flac file and from that separates it into it's individual songs
#############################################################################

import argparse

def ReadTrack(filepath):
        """
        Generates a list of tracks from a given file
        """
        ## some tracks don't have 00 and 01 index.
        ## keep track of the previous index to use as start
        previous = None
        ## keep track if we are in a track collecting metadata ?
        inTrack =  False
        ## which part of the collection are we ?
        stage = 0
        ## track data
        title = ""
        performer = ""
        s_index = 0
        e_index = 0

        with open(filepath, 'r') as f:
                for line in f:
                        ## check if we are currently collecting
                        if inTrack == False:
                                ## we are not collecting
                                ## see if we need to be
                                if 'TRACK' in line:
                                        inTrack = True
                                        continue

                        ## we are currently collecting
                        if 'TITLE' in line:
                                s = line.find('"')+1
                                e = line.rfind('"')
                                title = line[s:e]
                                stage = stage + 1
                                continue
                        if 'PERFORMER' in line:
                                s = line.find('"')+1
                                e = line.rfind('"')
                                performer = line[s:e]
                                stage = stage + 1
                                continue
                        if 'INDEX' in line:
                                if '01 ' in line:
                                        ## we don't have 2 indexes
                                        t = line.find('01 ')+3
                                        e_index = line[t:].strip()
                                        stage = 0
                                        #yield data
                                        inTrack = False
                                        if previous == None:
                                                s_index = '00:00:00'
                                                previous = e_index
                                        else:
                                                s_index = previous
                                                previous = e_index
                                        yield title,performer,s_index,e_index
                                ## we have two indexes
                                elif '00 ' in line and 3 == stage + 1:
                                        ## we have 2 indexes
                                        t = line.find('00 ')+3
                                        s_index = line[t:].strip()
                                        stage = stage + 1
                                        ## read second index
                                        line = f.readline()
                                        if '01 ' in line and 4 == stage + 1:
                                                t = line.find('01 ')+3
                                                e_index = line[t:].strip()
                                                stage = 0
                                                inTrack = False
                                                yield title,performer,s_index,e_index

def create_argparser():
        """
        creates and configures the argparser
        for use
        """
#  configure the argument parser
        parser = argparse.ArgumentParser(
                description=
                """
                Converts the tracks listed in a cue file
                to individual ['alac','flac'] files
                if no arguments are provided it will attempt to
                use 'readcue.txt' file with codec configured to alac
                """
        )

        parser.add_argument('-f', '--file',
                            help="takes a cue file as extra argument")

        # don't allow verbose with quiet at the same time

        group_vq = parser.add_mutually_exclusive_group()

        group_vq.add_argument('-v','--verbose', action='store_true',
                              help='increase output verbosity')

        group_vq.add_argument('-q', '--quiet', action='store_true',
                              help='no output messages will be displayed')

        parser.add_argument('-c', '--codec',
                            choices=['alac','flac'],
                            help='enables conversion to alac or flac file format')

        return parser

if __name__ == '__main__':
        parser = create_argparser()
        # parse the arguments
        args = parser.parse_args()

        cue_file = 'readcue.txt'
        if args.file != None:
                cue_file = args.file

        for _title,_performer,_idx,__idx in ReadTrack(cue_file):
                print("we got\n\t{}\n\t{}\n\t{}\n\t{}\n".format(_title,_performer,_idx,__idx))