import pickle
from typing import TYPE_CHECKING

from sqlalchemy import ForeignKey, Table, Column, UniqueConstraint, Index
from sqlalchemy.orm import Mapped, mapped_column, relationship

from models.base import BaseModel

if TYPE_CHECKING:
    from models import Project, BaseModel, Card

project_attribute = Table(
    'project_attribute',
    BaseModel.metadata,
    Column('project_id', ForeignKey('projects.id')),
    Column('attribute_id', ForeignKey('attributes.id')),
)


class AttributeType(BaseModel):
    __tablename__ = 'attribute_types'

    id: Mapped[int] = mapped_column(primary_key=True)
    type: Mapped[str] = mapped_column(nullable=False, unique=True)
    name: Mapped[str] = mapped_column(nullable=False, unique=True)
    is_deleted: Mapped[bool] = mapped_column(default=False)

    attributes: Mapped['Attribute'] = relationship(
        'Attribute',
        back_populates='type',
        lazy='noload',
    )


class Attribute(BaseModel):
    __tablename__ = 'attributes'

    id: Mapped[int] = mapped_column(primary_key=True)
    label: Mapped[str] = mapped_column(nullable=False)
    name: Mapped[str] = mapped_column(nullable=False, unique=True)
    is_applicable_to_group: Mapped[bool] = mapped_column(
        default=False,
        comment='Применять ли изменения атрибута карточки ко всем карточкам в группе',
    )
    is_nullable: Mapped[bool] = mapped_column(default=False, nullable=False)
    default_value: Mapped[bytes] = mapped_column(nullable=True)

    projects: Mapped[list['Project']] = relationship(
        'Project',
        uselist=True,
        secondary='project_attribute',
        back_populates='attributes',
        lazy='noload',
    )

    type_id: Mapped[int] = mapped_column(ForeignKey('attribute_types.id'), nullable=False)
    type: Mapped[AttributeType] = relationship(
        'AttributeType',
        back_populates='attributes',
        lazy='joined',
    )

    card_attributes: Mapped[list['CardAttribute']] = relationship(
        'CardAttribute',
        uselist=True,
        lazy='noload',
        back_populates='attribute',
    )


class CardAttribute(BaseModel):
    __tablename__ = 'card_attributes'

    id: Mapped[int] = mapped_column(primary_key=True)
    value: Mapped[bytes] = mapped_column(nullable=True)

    card_id: Mapped[int] = mapped_column(ForeignKey('cards.id'), nullable=False)
    card: Mapped['Card'] = relationship(
        'Card',
        back_populates='attributes',
        lazy='noload',
    )

    attribute_id: Mapped[int] = mapped_column(ForeignKey('attributes.id'), nullable=False)
    attribute: Mapped[Attribute] = relationship(
        'Attribute',
        back_populates='card_attributes',
        lazy='joined',
    )

    __table_args__ = (
        UniqueConstraint('card_id', 'attribute_id', name='uix_card_service'),
        Index('idx_card_id_attribute_id', 'card_id', 'attribute_id', unique=True)
    )

    def set_value(self, value):
        self.value = pickle.dumps(value)

    def get_value(self):
        return pickle.loads(self.value)