import json
import re
import glob
import os
import unicodedata
import hashlib
import mmap
import argparse


def make_metapackage(repodir, pkgname, pkgver, depends):
    dep = " ".join(depends)
    result = f"""
# Generated by musicrepo
pkgname={pkgname}
pkgver={pkgver}
pkgrel=0
pkgdesc="musicrepo"
options="!check"
url="https://music"
arch="noarch"
license="propriatary"
depends="{dep}"
    """
    result += '\npackage() {\n\tmkdir -p "$pkgdir"\n}\n'
    apkfile = os.path.join(repodir, pkgname, 'APKBUILD')
    apkdir = os.path.dirname(apkfile)
    os.makedirs(apkdir, exist_ok=True)

    with open(apkfile, 'w') as handle:
        handle.write(result)


def make_apkbuild(repodir, artist, album, path):
    artist_slug = slug(artist)
    album_slug = slug(album)
    pkgname = f"musicdir-{artist_slug}-{album_slug}"

    pkgver = 1
    if os.path.isfile(os.path.join(path, 'pkgver')):
        with open(os.path.join(path, 'pkgver')) as handle:
            raw = handle.read()
        pkgver = int(raw.strip())

    apkfile = os.path.join(repodir, pkgname, 'APKBUILD')
    apkdir = os.path.dirname(apkfile)
    os.makedirs(apkdir, exist_ok=True)
    os.makedirs(os.path.join(apkdir, "tracks"), exist_ok=True)

    sources = ""
    sha512sums = []
    for file in glob.glob(os.path.join(path, '*')):
        sname = "tracks/" + os.path.basename(file).replace(' ', '-')
        sources += f"{sname}\n"
        if not os.path.islink(os.path.join(apkdir, sname)):
            os.symlink(file, os.path.join(apkdir, sname))

        h = get_sha512sum(file)
        hname = os.path.basename(sname)
        sha512sums.append(f"{h}  {hname}")
    sha512sums = "\n".join(sha512sums)

    result = f"""
# Generated by musicrepo
pkgname={pkgname}
_artist="{artist}"
_album="{album}"
pkgver={pkgver}
pkgrel=0
pkgdesc="{album} from {artist}"
url="https://music"
arch="noarch"
license="propriatary"
options="!check"
source="
{sources}
"
    """
    result += """
package()
{
    cd tracks
    for _i in ./*; do
        install -Dm644 "$_i" "$pkgdir"/usr/share/music/"$_artist"/"$_album"/"$_i"
    done
}
    """

    result += f'\nsha512sums="{sha512sums}"\n'

    with open(apkfile, 'w') as handle:
        handle.write(result)

    return pkgname, pkgver


def slug(value):
    value = unicodedata.normalize('NFKD', value).encode('ascii', 'ignore').decode('ascii')
    value = re.sub('[^\w\s-]', '', value).strip().lower()
    return re.sub('[-\s]+', '-', value)


def get_sha512sum(filename):
    h = hashlib.sha512()
    with open(filename, 'rb') as f:
        with mmap.mmap(f.fileno(), 0, prot=mmap.PROT_READ) as mm:
            h.update(mm)
    return h.hexdigest()


def make_repository(musicdir, repodir):
    music = {}
    statefile = os.path.join(repodir, 'musicrepo.state.json')
    state = {}
    bump = set()
    if os.path.isfile(statefile):
        with open(statefile) as handle:
            state = json.loads(handle.read())

    for path in glob.glob(os.path.join(musicdir, '*/*'), recursive=True):
        part = path.split('/')
        album = part[-1]
        artist = part[-2]

        match = re.match(r'(.+)\(\d\d\d\d\)', album)
        if match:
            album = match.groups(0)[0].strip()

        if artist not in music:
            music[artist] = {}

        music[artist][album] = path

    artist_pkgs = []
    for artist in music:
        albums_pkgs = []
        for album in music[artist]:
            path = music[artist][album]
            pkgname, pkgver = make_apkbuild(repodir, artist, album, path)
            albums_pkgs.append(pkgname)
            artist_slug = slug(artist)

            if pkgname not in state:
                print(f"New album: {album} from {artist}")
                bump.add(f'musicdir-{artist_slug}')
                state[pkgname] = pkgver

        if len(albums_pkgs):
            pkgname = f'musicdir-{artist_slug}'
            pkgver = 0
            if pkgname in state:
                pkgver = state[pkgname]
            else:
                print(f"Artist {artist} is new, creating metapackage")
                state[pkgname] = 0
                bump.add('musicdir-all')
            if pkgname in bump:
                state[pkgname] += 1
                pkgver += 1
                print(f"Artist {artist} has new album packages, bumping version to {pkgver}")
            make_metapackage(repodir, pkgname, pkgver, albums_pkgs)
            artist_pkgs.append(f'musicdir-{artist_slug}')

    if 'musicdir-all' not in state:
        state['musicdir-all'] = 0
    if 'musicdir-all' in bump:
        state['musicdir-all'] += 1
        print(f"Artist list changed, bumping musicdir-all to {state['musicdir-all']}")
    make_metapackage(repodir, 'musicdir-all', state['musicdir-all'], artist_pkgs)

    with open(statefile, 'w') as handle:
        handle.write(json.dumps(state))


def main():
    parser = argparse.ArgumentParser(description="music repo generator")
    parser.add_argument('musicdir')
    parser.add_argument('repodir')
    args = parser.parse_args()

    make_repository(os.path.expanduser(args.musicdir), os.path.expanduser(args.repodir))


if __name__ == '__main__':
    main()