#!/usr/bin/python3
# ex: set filetype=python

import argparse
import os
import urllib.parse
import xml.etree.cElementTree as xml
from mutagen.easyid3 import EasyID3
from mutagen.mp3 import MP3
from shutil import copyfile



class Track():
    """
    Stores all the information of a track inside an object.
    Can be used to easily access the tracks stored in the database.
    """

    def __init__(self, xml_doc):
        it = iter(xml_doc)
        for k, v in zip(it, it):
            setattr(self, k.text.replace(' ', ''), v.text)


def parseXml(xml_file):
    """
    Parses an xml file and returns the DOM tree.
    """
    tree = xml.parse(xml_file)
    root = tree.getroot()
    tracks = []
    for t in root.findall('.//dict/dict/dict'):
        tracks.append(Track(t))
    return tracks


def copy_file(track: Track, targetFolder, cnt, max) -> str:
    """
    Copies a track from its source to the destination folder
    """
    path = urllib.parse.unquote(track.Location[7:])
    dst = os.path.join(targetFolder, os.path.basename(path))
    if (os.path.exists(path)):
        print('Copying file {0} [{1}/{2}]'.format(path,cnt,max))
        copyfile(path, dst)
    else:
        print('File {0} not found.'.format(path))
        return None
    return dst


def tag_file(track: Track, file_name: str, cnt, max):
    """
    Adds ID3 tags to a file.
    """
    if not file_name.endswith('.mp3'):
        print('Skipping file {0}. It\'s not an mp3 file. [{1}/{2}]'
              .format(file_name, cnt, max))
        return

    print('Tagging file {0} [{1}/{2}]'.format(file_name, cnt, max))
    mp3file = MP3(file_name, ID3=EasyID3)
    if hasattr(track, 'Album'):
        mp3file['album'] = track.Album
    if hasattr(track, 'BPM'):
        mp3file['bpm'] = track.BPM
    if hasattr(track, 'Compilation'):
        mp3file['compilation'] = 'true'
    if hasattr(track, 'Composer'):
        mp3file['composer'] = track.Composer
    if hasattr(track, 'TotalTime'):
        mp3file['length'] = track.TotalTime
    if hasattr(track, 'Name'):
        mp3file['title'] = track.Name
    if hasattr(track, 'Artist'):
        mp3file['artist'] = track.Artist
    if hasattr(track, 'AlbumArtist'):
        mp3file['albumartist'] = track.AlbumArtist
    if hasattr(track, 'DiscNumber'):
        mp3file['discnumber'] = track.DiscNumber
    if hasattr(track, 'TrackNumber'):
        if hasattr(track, 'TrackCount'):
            mp3file['tracknumber'] = '{0}/{1}'.format(track.TrackNumber,
                                                      track.TrackCount)
        else:
            mp3file['tracknumber'] = track.TrackNumber
    if hasattr(track, 'Genre'):
        mp3file['genre'] = track.Genre
    mp3file.save()


def main():
    """
    Setup our main program
    """
    parser = argparse.ArgumentParser()
    parser.add_argument('-t', '--target', type=str,
                        help='The target path to store the scraped \
                                                          files into',
                        default='~/itunesscrape')
    parser.add_argument('-l', '--logfile', type=str,
                        help='The path to the logfile to use.',
                        default='~/itunesscrape.log')
    parser.add_argument('libraryFile',
                        help='The iTunes library file in XML format.')
    args = parser.parse_args()

    print('Parsing library file...')
    tracks = parseXml(args.libraryFile)
    print('{0} tracks found.'.format(len(tracks)))

    if not os.path.isdir(args.target):
        os.mkdir(args.target)

    count = 0
    maxcount = len(tracks)
    for t in tracks:
        count += 1
        new_file = copy_file(t, args.target)
        if new_file is not None:
            tag_file(t, new_file)

    print('Done. Copied {0} of {1} files.'.format(count, maxcount))


if __name__ == "__main__":
    main()