serializers.py

from django.conf import settings
from rest_framework import serializers
from taggit.models import Tag

from funkwhale_api.music.serializers import TrackSerializerNested

from . import models


class PlaylistTrackSerializer(serializers.ModelSerializer):
    track = TrackSerializerNested()

    class Meta:
        model = models.PlaylistTrack
        fields = ('id', 'track', 'playlist', 'position')


class PlaylistTrackCreateSerializer(serializers.ModelSerializer):

    class Meta:
        model = models.PlaylistTrack
        fields = ('id', 'track', 'playlist', 'index')

    def validate_playlist(self, value):
        existing = value.playlist_tracks.count()
        if existing >= settings.PLAYLISTS_MAX_TRACKS:
            raise serializers.ValidationError(
                'Playlist has reached the maximum of {} tracks'.format(
                    settings.PLAYLISTS_MAX_TRACKS))
        return value


class PlaylistSerializer(serializers.ModelSerializer):

    class Meta:
        model = models.Playlist
        fields = ('id', 'name', 'privacy_level', 'creation_date')
        read_only_fields = ['id', 'creation_date']