"""Model representing a release artist."""

from flask import g
from oto import response
import sqlalchemy

from product_digital.connectors import mysql


class ReleaseArtist(mysql.BaseModel):
    """Release artist model."""

    __tablename__ = 'release_artist'

    release_artist_id = sqlalchemy.Column(
        sqlalchemy.Integer, primary_key=True, autoincrement=True,
        nullable=False)
    release_id = sqlalchemy.Column(sqlalchemy.Integer, nullable=False)
    upc = sqlalchemy.Column(sqlalchemy.BigInteger, nullable=False)
    role = sqlalchemy.Column(sqlalchemy.String, nullable=False)
    artist_name = sqlalchemy.Column(sqlalchemy.String, nullable=False)
    url = sqlalchemy.Column(sqlalchemy.String, nullable=True)
    artist_info_id = sqlalchemy.Column(sqlalchemy.Integer, nullable=True)

    def to_dict(self):
        """Return dictionary of release artist data.

        Returns:
            dict: release artist metadata.
        """
        return {
            'release_artist_id': self.release_artist_id,
            'release_id': self.release_id,
            'upc': self.upc,
            'role': self.role,
            'artist_name': self.artist_name,
            'artist_info_id': self.artist_info_id
        }


@mysql.wrap_db_errors
def get_release_artists_by_release_id(release_id):
    """Get all of the release artists for the given release.

    Args:
        release_id (int): id of the release.

    Returns:
        response.Response: response containing payload of release artists.
    """
    release_artist_dicts = []

    with mysql.db_session() as session:
        release_artists = session.query(ReleaseArtist).filter_by(
            release_id=release_id)
        for release_artist in release_artists:
            release_artist_dicts.append(release_artist.to_dict())

    return response.Response(message=release_artist_dicts)


@mysql.wrap_db_errors
def save_for_release_id(release_id, upc, release_artists):
    """Overwrite all of the release artists for the given release.

    Args:
        release_id (int): id of the release.
        upc (int): upc of the release.
        release_artists (list): list of dicts containing release artist data.

    Returns:
        response.Response: response object containing status and payload.
    """
    release_artist_dicts = []

    with mysql.db_session() as session:
        for release_artist_data in release_artists:
            release_artist_id = release_artist_data.get('release_artist_id')
            if release_artist_id:
                release_artist = session.query(ReleaseArtist)\
                    .get(release_artist_id)
                for key, value in release_artist_data.items():
                    setattr(release_artist, key, value)
            else:
                release_artist_data_copy = release_artist_data.copy()
                release_artist_data_copy['release_id'] = release_id
                release_artist_data_copy['upc'] = upc
                release_artist = ReleaseArtist(**release_artist_data_copy)
                session.add(release_artist)

            session.flush()
            release_artist_dicts.append(release_artist.to_dict())

        if (
            not hasattr(g, 'is_non_destructive_update') or not g.is_non_destructive_update
        ):
            # Delete all release artists that are not in the new list.
            release_artist_ids = [
                release_artist['release_artist_id']
                for release_artist in release_artist_dicts
            ]
            (session.query(ReleaseArtist)
                .filter_by(release_id=release_id)
                .filter(
                    ~ReleaseArtist.release_artist_id.in_(release_artist_ids))
                .delete(synchronize_session=False))

    return response.Response(message=release_artist_dicts)


def delete(product_id, session):
    """Delete release_artist entry for the product."""
    session.query(ReleaseArtist) \
        .filter(ReleaseArtist.release_id == product_id) \
        .delete()