"""Instant Grats Persister.

Handles doing CRUD operations on the track_instant_grat and related tables.
"""
from sqlalchemy import Column
from sqlalchemy import DateTime
from sqlalchemy import Enum
from sqlalchemy import ForeignKey
from sqlalchemy import func
from sqlalchemy import Integer
from sqlalchemy import TIMESTAMP

from backend.connectors import mysql


class InstantGrat(mysql.BaseModel):
    """Encapsulates Instant Grat data.

    Represents track_instant_grat table in the art_relations database.
    Instant Grats is a form which is being used in both ALW and OA
    and can be viewed/edited from both platforms. Each Instant Grat belongs to
    one track and one store. Instant Gratification allows customers to release
    some tracks of product before actual product release date.
    """

    __tablename__ = 'track_instant_grat'

    instant_grat_id = Column(
        'id', Integer, primary_key=True, autoincrement=True, nullable=False)
    tuid = Column(
        'unique_track_id', ForeignKey('track.id'), nullable=False)
    store_id = Column(
        'customer_master_master_id', Integer, nullable=False)
    active = Column(
        'active', Enum('Y', 'N'), default='Y', nullable=False)
    date = Column('date', DateTime, nullable=True)
    user_id = Column('added_by_user_id', Integer, nullable=True)
    user_type = Column('added_by_user_type', Enum('oa', 'alw'), default='oa')
    date_created = Column(
        'date_created', TIMESTAMP, server_default=func.now(),
        server_onupdate=func.now())

    @property
    def created_by(self):
        """String in format 'user_type:user_id' if type and id exist.

        Returns None if at least one of those fields is empty.
        """
        return (
            '{account_type}:{account_id}'.format(
                account_type=str(self.user_type),
                account_id=str(self.user_id))
            if self.user_id and self.user_type else '')

    def to_dict(self):
        """Python dict representation of Instant Grats model."""
        return {
            'tuid': self.tuid,
            'store_id': self.store_id,
            'date': self.date,
            'created_by': self.created_by,
            'created_at': self.date_created,
            'active': self.active
        }