#!/usr/bin/python3
import music_tag
import os
import sys
import subprocess

def show_help():
    print("Usage: " + sys.argv[0] + " <mp3file> <command> {value}")
    print("  commands:")
    print("    album albumartist")
    print("    comment compilation composer")
    print("    discnumber")
    print("    genre")
    print("    rename")
    print("    totaldiscs totaltracks tracknumber tracktitle")
    print("    year")

if len(sys.argv) < 2:
    show_help()
    sys.exit()

filename = sys.argv[1]
mp3 = music_tag.load_file(filename)

if len(sys.argv) < 3:
    show_tags(mp3)
    sys.exit()

command = sys.argv[2]

# Dictionary to map commands to functions or subprocess commands
command_actions = {
    'rename': lambda: rename_mp3(mp3, filename),
    'folder': lambda: move_to_album_folder(mp3, filename),
    '_folder': lambda: move_to_parent_album_folder(mp3, filename),
    '~comment': lambda: remove_tag(mp3, 'comment'),
    '~albumartist': lambda: remove_tag(mp3, 'albumartist'),
    'album': lambda value: set_tag(mp3, 'album', value),
    'albumartist': lambda value: set_tag(mp3, 'albumartist', value),
    'artist': lambda value: set_tag(mp3, 'artist', value),
    'comment': lambda value: set_tag(mp3, 'comment', value),
    'composer': lambda value: set_tag(mp3, 'composer', value),
    'discnumber': lambda value: set_tag(mp3, 'discnumber', value),
    'totaldiscs': lambda value: set_tag(mp3, 'totaldiscs', value),
    'genre': lambda value: set_tag(mp3, 'genre', value),
    'totaltracks': lambda value: set_tag(mp3, 'totaltracks', value),
    'tracktitle': lambda value: set_tag(mp3, 'tracktitle', value),
    'tracknumber': lambda value: set_tag(mp3, 'tracknumber', value),
    'year': lambda value: set_tag(mp3, 'year', value),
}

if command in command_actions:
    if len(sys.argv) < 4:
        print("Value is missing!")
        sys.exit()
    
    value = sys.argv[3]
    command_actions[command](value)
else:
    print("Unknown command:", command)
    sys.exit()

def rename_mp3(mp3, filename):
    newfilename = f"{mp3['tracknumber'].value.zfill(3)}.{mp3['tracktitle']}.{bitrate_kbps(mp3)}.mp3"
    subprocess.run(['mv', filename, newfilename])

def move_to_album_folder(mp3, filename):
    folder = mp3['album']
    subprocess.run(['mkdir', folder])
    subprocess.run(['mv', filename, folder])

def move_to_parent_album_folder(mp3, filename):
    folder = mp3['album']
    subprocess.run(['mkdir', f'../{folder}'])
    subprocess.run(['mv', filename, f'../{folder}'])

def remove_tag(mp3, tag):
    mp3.remove_tag(tag)
    mp3.save()
    print(f"{tag} removed!")

def set_tag(mp3, tag, value):
    old_value = str(mp3[tag].value)
    mp3[tag] = value
    new_value = str(mp3[tag].value)
    mp3.save()
    print(f"{tag}: {old_value} -> {new_value}")

def bitrate_kbps(mp3):
    bitrate = int(int(mp3['#bitrate']) / 1000)
    return f"{bitrate}kbps"

def show_tags(mp3):
    print(f"{mp3['artist']} / {mp3['album']} / {mp3['tracknumber'].value.zfill(3)}.{mp3['tracktitle']}")
    print("========")
    print(f"album                      : {mp3['album']}")
    print(f"albumartist                : {mp3['albumartist']}")
    print(f"artist                     : {mp3['artist']}")
    print(f"artwork                    : {mp3['artwork']}")
    print(f"comment                    : {mp3['comment']}")
    print(f"compilation                : {mp3['compilation']}")
    print(f"composer                   : {mp3['composer']}")
    print(f"discnumber / totaldiscs    : {mp3['discnumber'].value} / {mp3['totaldiscs'].value}")
    print(f"genre                      : {mp3['genre']}")
    print(f"tracknumber / totaltracks  : {mp3['tracknumber'].value} / {mp3['totaltracks'].value}")
    print(f"tracktitle                 : {mp3['tracktitle']}")
    print(f"year                       : {mp3['year']}")
    print(f"isrc                       : {mp3['isrc']}")
    length = mp3['#length'].value
    min = int(length / 60)
    sec = int(length - min * 60 + .5)
    print("---")
    print(f"{bitrate_kbps(mp3)} / {mp3['#codec']} / {min}m{sec}s / {mp3['#channels']} channels / {mp3['#samplerate'] / 1000}kHz")