import logging
import os

from django.conf import settings
from django.core.files.base import ContentFile
from musicbrainzngs import ResponseError

from funkwhale_api.common import preferences
from funkwhale_api.federation import activity, actors
from funkwhale_api.federation import serializers as federation_serializers
from funkwhale_api.providers.acoustid import get_acoustid_client
from funkwhale_api.providers.audiofile import tasks as audiofile_tasks
from funkwhale_api.taskapp import celery

from . import lyrics as lyrics_utils
from . import models
from . import utils as music_utils

logger = logging.getLogger(__name__)


@celery.app.task(name="acoustid.set_on_track_file")
@celery.require_instance(models.TrackFile, "track_file")
def set_acoustid_on_track_file(track_file):
    client = get_acoustid_client()
    result = client.get_best_match(track_file.audio_file.path)

    def update(id):
        track_file.acoustid_track_id = id
        track_file.save(update_fields=["acoustid_track_id"])
        return id

    if result:
        return update(result["id"])


def import_track_from_remote(library_track):
    metadata = library_track.metadata
    try:
        track_mbid = metadata["recording"]["musicbrainz_id"]
        assert track_mbid  # for null/empty values
    except (KeyError, AssertionError):
        pass
    else:
        return models.Track.get_or_create_from_api(mbid=track_mbid)[0]

    try:
        album_mbid = metadata["release"]["musicbrainz_id"]
        assert album_mbid  # for null/empty values
    except (KeyError, AssertionError):
        pass
    else:
        album, _ = models.Album.get_or_create_from_api(mbid=album_mbid)
        return models.Track.get_or_create_from_title(
            library_track.title, artist=album.artist, album=album
        )[0]

    try:
        artist_mbid = metadata["artist"]["musicbrainz_id"]
        assert artist_mbid  # for null/empty values
    except (KeyError, AssertionError):
        pass
    else:
        artist, _ = models.Artist.get_or_create_from_api(mbid=artist_mbid)
        album, _ = models.Album.get_or_create_from_title(
            library_track.album_title, artist=artist
        )
        return models.Track.get_or_create_from_title(
            library_track.title, artist=artist, album=album
        )[0]

    # worst case scenario, we have absolutely no way to link to a
    # musicbrainz resource, we rely on the name/titles
    artist, _ = models.Artist.get_or_create_from_name(library_track.artist_name)
    album, _ = models.Album.get_or_create_from_title(
        library_track.album_title, artist=artist
    )
    return models.Track.get_or_create_from_title(
        library_track.title, artist=artist, album=album
    )[0]


def _do_import(import_job, use_acoustid=False):
    logger.info("[Import Job %s] starting job", import_job.pk)
    from_file = bool(import_job.audio_file)
    mbid = import_job.mbid
    replace = import_job.replace_if_duplicate
    acoustid_track_id = None
    duration = None
    track = None
    # use_acoustid = use_acoustid and preferences.get('providers_acoustid__api_key')
    # Acoustid is not reliable, we disable it for now.
    use_acoustid = False
    if not mbid and use_acoustid and from_file:
        # we try to deduce mbid from acoustid
        client = get_acoustid_client()
        match = client.get_best_match(import_job.audio_file.path)
        if match:
            duration = match["recordings"][0]["duration"]
            mbid = match["recordings"][0]["id"]
            acoustid_track_id = match["id"]
    if mbid:
        logger.info(
            "[Import Job %s] importing track from musicbrainz recording %s",
            import_job.pk,
            str(mbid),
        )
        track, _ = models.Track.get_or_create_from_api(mbid=mbid)
    elif import_job.audio_file:
        logger.info(
            "[Import Job %s] importing track from uploaded track data at %s",
            import_job.pk,
            import_job.audio_file.path,
        )
        track = audiofile_tasks.import_track_data_from_path(import_job.audio_file.path)
    elif import_job.library_track:
        logger.info(
            "[Import Job %s] importing track from federated library track %s",
            import_job.pk,
            import_job.library_track.pk,
        )
        track = import_track_from_remote(import_job.library_track)
    elif import_job.source.startswith("file://"):
        tf_path = import_job.source.replace("file://", "", 1)
        logger.info(
            "[Import Job %s] importing track from local track data at %s",
            import_job.pk,
            tf_path,
        )
        track = audiofile_tasks.import_track_data_from_path(tf_path)
    else:
        raise ValueError(
            "Not enough data to process import, "
            "add a mbid, an audio file or a library track"
        )

    track_file = None
    if replace:
        logger.info("[Import Job %s] deleting existing audio file", import_job.pk)
        track.files.all().delete()
    elif track.files.count() > 0:
        logger.info(
            "[Import Job %s] skipping, we already have a file for this track",
            import_job.pk,
        )
        if import_job.audio_file:
            import_job.audio_file.delete()
        import_job.status = "skipped"
        import_job.save()
        return

    track_file = track_file or models.TrackFile(track=track, source=import_job.source)
    track_file.acoustid_track_id = acoustid_track_id
    if from_file:
        track_file.audio_file = ContentFile(import_job.audio_file.read())
        track_file.audio_file.name = import_job.audio_file.name
        track_file.duration = duration
    elif import_job.library_track:
        track_file.library_track = import_job.library_track
        track_file.mimetype = import_job.library_track.audio_mimetype
        if import_job.library_track.library.download_files:
            raise NotImplementedError()
        else:
            # no downloading, we hotlink
            pass
    elif not import_job.audio_file and not import_job.source.startswith("file://"):
        # not an inplace import, and we have a source, so let's download it
        logger.info("[Import Job %s] downloading audio file from remote", import_job.pk)
        track_file.download_file()
    elif not import_job.audio_file and import_job.source.startswith("file://"):
        # in place import, we set mimetype from extension
        path, ext = os.path.splitext(import_job.source)
        track_file.mimetype = music_utils.get_type_from_ext(ext)
    track_file.set_audio_data()
    track_file.save()
    # if no cover is set on track album, we try to update it as well:
    if not track.album.cover:
        logger.info("[Import Job %s] retrieving album cover", import_job.pk)
        update_album_cover(track.album, track_file)
    import_job.status = "finished"
    import_job.track_file = track_file
    if import_job.audio_file:
        # it's imported on the track, we don't need it anymore
        import_job.audio_file.delete()
    import_job.save()
    logger.info("[Import Job %s] job finished", import_job.pk)
    return track_file


def update_album_cover(album, track_file, replace=False):
    if album.cover and not replace:
        return

    if track_file:
        # maybe the file has a cover embedded?
        try:
            metadata = track_file.get_metadata()
        except FileNotFoundError:
            metadata = None
        if metadata:
            cover = metadata.get_picture("cover_front")
            if cover:
                # best case scenario, cover is embedded in the track
                logger.info("[Album %s] Using cover embedded in file", album.pk)
                return album.get_image(data=cover)
        if track_file.source and track_file.source.startswith("file://"):
            # let's look for a cover in the same directory
            path = os.path.dirname(track_file.source.replace("file://", "", 1))
            logger.info("[Album %s] scanning covers from %s", album.pk, path)
            cover = get_cover_from_fs(path)
            if cover:
                return album.get_image(data=cover)
    if not album.mbid:
        return
    try:
        logger.info(
            "[Album %s] Fetching cover from musicbrainz release %s",
            album.pk,
            str(album.mbid),
        )
        return album.get_image()
    except ResponseError as exc:
        logger.warning(
            "[Album %s] cannot fetch cover from musicbrainz: %s", album.pk, str(exc)
        )


IMAGE_TYPES = [("jpg", "image/jpeg"), ("png", "image/png")]


def get_cover_from_fs(dir_path):
    if os.path.exists(dir_path):
        for e, m in IMAGE_TYPES:
            cover_path = os.path.join(dir_path, "cover.{}".format(e))
            if not os.path.exists(cover_path):
                logger.debug("Cover %s does not exists", cover_path)
                continue
            with open(cover_path, "rb") as c:
                logger.info("Found cover at %s", cover_path)
                return {"mimetype": m, "content": c.read()}


@celery.app.task(name="ImportJob.run", bind=True)
@celery.require_instance(
    models.ImportJob.objects.filter(status__in=["pending", "errored"]), "import_job"
)
def import_job_run(self, import_job, use_acoustid=False):
    def mark_errored(exc):
        logger.error("[Import Job %s] Error during import: %s", import_job.pk, str(exc))
        import_job.status = "errored"
        import_job.save(update_fields=["status"])

    try:
        tf = _do_import(import_job, use_acoustid=use_acoustid)
        return tf.pk if tf else None
    except Exception as exc:
        if not settings.DEBUG:
            try:
                self.retry(exc=exc, countdown=30, max_retries=3)
            except Exception:
                mark_errored(exc)
                raise
        mark_errored(exc)
        raise


@celery.app.task(name="ImportBatch.run")
@celery.require_instance(models.ImportBatch, "import_batch")
def import_batch_run(import_batch):
    for job_id in import_batch.jobs.order_by("id").values_list("id", flat=True):
        import_job_run.delay(import_job_id=job_id)


@celery.app.task(name="Lyrics.fetch_content")
@celery.require_instance(models.Lyrics, "lyrics")
def fetch_content(lyrics):
    html = lyrics_utils._get_html(lyrics.url)
    content = lyrics_utils.extract_content(html)
    cleaned_content = lyrics_utils.clean_content(content)
    lyrics.content = cleaned_content
    lyrics.save(update_fields=["content"])


@celery.app.task(name="music.import_batch_notify_followers")
@celery.require_instance(
    models.ImportBatch.objects.filter(status="finished"), "import_batch"
)
def import_batch_notify_followers(import_batch):
    if not preferences.get("federation__enabled"):
        return

    if import_batch.source == "federation":
        return

    library_actor = actors.SYSTEM_ACTORS["library"].get_actor_instance()
    followers = library_actor.get_approved_followers()
    jobs = import_batch.jobs.filter(
        status="finished", library_track__isnull=True, track_file__isnull=False
    ).select_related("track_file__track__artist", "track_file__track__album__artist")
    track_files = [job.track_file for job in jobs]
    collection = federation_serializers.CollectionSerializer(
        {
            "actor": library_actor,
            "id": import_batch.get_federation_url(),
            "items": track_files,
            "item_serializer": federation_serializers.AudioSerializer,
        }
    ).data
    for f in followers:
        create = federation_serializers.ActivitySerializer(
            {
                "type": "Create",
                "id": collection["id"],
                "object": collection,
                "actor": library_actor.url,
                "to": [f.url],
            }
        ).data

        activity.deliver(create, on_behalf_of=library_actor, to=[f.url])