# Copyright 2016 Christoph Reiter
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.

try:
    import musicbrainzngs
except ImportError:
    from quodlibet import plugins
    raise plugins.MissingModulePluginException("musicbrainzngs")

from quodlibet import app
from quodlibet import const
from quodlibet import util


VARIOUS_ARTISTS_ARTISTID = '89ad4ac3-39f7-470e-963a-56509c546377'


def is_mbid(id_):
    return len(id_) == 36


def search_releases(query):
    """Returns a list of ReleaseResult or raises MusicBrainzError"""

    musicbrainzngs.set_useragent(app.name, const.VERSION)
    return [Release(r) for r in
            musicbrainzngs.search_releases(query)["release-list"]]


def _get_release(release_id):
    """Returns a release containing all recordings and artists or raises
    MusicBrainzError
    """

    assert is_mbid(release_id)

    return musicbrainzngs.get_release_by_id(
        release_id,
        includes=["recordings", "artists", "artist-credits", "labels"]
    )["release"]


class Artist:

    def __init__(self, name, sort_name, id_):
        self.name = name
        self.sort_name = sort_name
        self.id = id_  # MusicBrainz Artist ID / Album Artist ID

    @property
    def is_various(self):
        return self.id == VARIOUS_ARTISTS_ARTISTID

    @classmethod
    def from_credit(cls, mbcredit):
        artists = []
        for credit in mbcredit:
            try:
                artist = credit["artist"]
            except TypeError:
                # join strings
                pass
            else:
                artists.append(
                    Artist(artist["name"], artist["sort-name"], artist["id"]))
        return artists


class ReleaseTrack:
    """Part of a Release, combines per track and per medium data"""

    def __init__(self, mbtrack, discnumber, track_count, disctitle):
        self._mbtrack = mbtrack
        self.discnumber = discnumber
        self.track_count = track_count
        self.disctitle = disctitle

    @property
    def id(self):
        """MusicBrainz release track ID"""

        return self._mbtrack["id"]

    @property
    def artists(self):
        return Artist.from_credit(self._mbtrack["artist-credit"])

    @property
    def title(self):
        return self._mbtrack["recording"]["title"]

    @property
    def tracknumber(self):
        return self._mbtrack["position"]


class Release:

    def __init__(self, mbrelease):
        self._mbrelease = mbrelease

    @property
    def labelid(self):
        label_list = self._mbrelease.get("label-info-list", [])
        if not label_list:
            return u""
        return label_list[0].get("catalog-number", u"")

    @property
    def id(self):
        """MusicBrainz release ID"""

        return self._mbrelease["id"]

    @property
    def date(self):
        return self._mbrelease.get("date", u"")

    @property
    def medium_format(self):
        formats = []
        for medium in self._mbrelease["medium-list"]:
            format_ = medium.get("format", u"")
            if format_:
                formats.append(format_)
        formats = util.list_unique(formats)
        return u"/".join(formats)

    @property
    def country(self):
        return self._mbrelease.get("country", u"")

    @property
    def disc_count(self):
        return self._mbrelease["medium-count"]

    @property
    def track_count(self):
        """Number of tracks for all included mediums"""

        track_count = 0
        for medium in self._mbrelease["medium-list"]:
            if "track-count" in medium:
                track_count += medium["track-count"]
            if "pregap" in medium:
                track_count += 1
        return track_count

    @property
    def tracks(self):
        tracks = []
        for medium in self._mbrelease["medium-list"]:
            disc = medium["position"]
            title = medium.get("title", u"")
            track_count = medium["track-count"]
            if "pregap" in medium:
                track_count += 1
                tracks.append(
                    ReleaseTrack(medium["pregap"], disc, track_count, title))
            for track in medium["track-list"]:
                tracks.append(ReleaseTrack(track, disc, track_count, title))
        return tracks

    @property
    def title(self):
        return self._mbrelease["title"]

    @property
    def is_single_artist(self):
        """If all tracks have the same artists as the release"""

        ids = [a.id for a in self.artists]
        for track in self.tracks:
            track_ids = [a.id for a in track.artists]
            if ids != track_ids:
                return False
        return True

    @property
    def is_various_artists(self):
        artists = self.artists
        return len(artists) == 1 and artists[0].is_various

    @property
    def artists(self):
        return Artist.from_credit(self._mbrelease["artist-credit"])

    def fetch_full(self):
        """Returns a new Release instance containing more info
        or raises MusicBrainzError

        This method is blocking...
        """

        return Release(_get_release(self.id))
