from rest_framework import serializers

from taggit.managers import TaggableManager
from rp.models import Article


class TagListSerializer(serializers.Field):
    class Meta:
        model = TaggableManager(blank=True)

    def to_representation(self, obj):
        if type(obj) is not list:
            return [tag.name for tag in obj.all()]
        return obj

    def to_internal_value(self, data):
        return [tag.strip() for tag in data.split(",")]


class ArticleSerializer(serializers.ModelSerializer):
    #: List of short tags to describe the article (eg. "Privacy", "Copyright")
    tags = TagListSerializer(help_text="""
        List of short tags to describe the article (eg."Privacy, Copyright").
        Must be a list of tags, coma separated (or an empty string).
        """)
    und_score_up = serializers.IntegerField(
            required=False,
            help_text="This is used to increase the vote count by this value")
    und_score_down = serializers.IntegerField(
            required=False,
            help_text="This is used to decrease the vote count by this value")
    und_score = serializers.IntegerField(
            required=False,
            help_text="This is the actual computed score for an Article")

    class Meta:
        model = Article
        fields = ('id', 'url', 'title', 'tags', 'extracts', 'status',
                  'und_score_up', 'und_score_down', 'und_score')

    def create(self, validated_data):
        article = Article.add_new_url(**validated_data)
        article.save()
        return article