# more info on the M3U file format available here:
# http://n4k3d.com/the-m3u-file-format/

import sys
import hexdump
import codecs

class track():
    def __init__(self, length, title, path, attrs=None):
        self.length = length
        self.title = title
        self.path = path
        self.attrs = attrs


# # # song info lines are formatted like:
#EXTINF:419,Alice In Chains - Rotten Apple
# length (seconds)
# Song title
# # # file name - relative or absolute path of file
# ..\Minus The Bear - Planet of Ice\Minus The Bear_Planet of Ice_01_Burying Luck.mp3
def parseM3U(infile):
    inf = open(infile,'r')

    # # # all m3u files should start with this line:
        #EXTM3U
    # this is not a valid M3U and we should stop..
    line = inf.readline()
    line = line.lstrip('\xef\xbb\xbf')
    line = line.rstrip('\n')
    line = line.strip()
    if not line.startswith('#EXTM3U'):
       return

    # initialize playlist variables before reading file
    playlist=[]
    song=track(None,None,None)

    for line in inf:
        line = line.lstrip('\xef\xbb\xbf')
        line = line.rstrip('\n')
        line = line.strip()
        if line.startswith('#EXTINF:'):
            # pull length and title from #EXTINF line
            prefix,title=line.split('#EXTINF:')[1].split(',',1)
            title=title.strip()
            length,attrstr=prefix.split(' ',1)
            attrs={}

            while attrstr:

              attrstr=attrstr.strip()
              key,tail=attrstr.split('=',1)
              if tail[0]=='\"':
                tail=tail[1:]
                value,attrstr=tail.split('"',1)
              else:
                try:
                  value,attrstr=tail.split(' ',1)
                except ValueError:
                  value=tail
                  attrstr=''
              attrstr=attrstr.strip()
              attrs[key]=value 
            
            title=title.decode('string_escape')
            song=track(length,title,None,attrs)
        elif (len(line) != 0):
            # pull song path from all other, non-blank lines
            song.path=line
            playlist.append(song)

            # reset the song variable so it doesn't use the same EXTINF more than once
            song=track(None,None,None)

    inf.close()

    return playlist

# for now, just pull the track info and print it onscreen
# get the M3U file path from the first command line argument
def main():
    m3ufile=sys.argv[1]
    playlist = parseM3U(m3ufile)
    for track in playlist:
        print (track.title, track.length, track.path)

if __name__ == '__main__':
    main()