import datetime

from sqlalchemy import Date, ForeignKey, Integer, UniqueConstraint
from sqlalchemy.orm import Mapped, mapped_column, relationship

from fooder.domain.base import Base, CommonMixin
from fooder.domain.meal import Meal


class Diary(Base, CommonMixin):
    """Diary represents user diary for given day."""

    __table_args__ = (UniqueConstraint("user_id", "date"),)

    meals: Mapped[list[Meal]] = relationship(
        lazy="selectin", order_by=Meal.order.desc()
    )
    date: Mapped[datetime.date] = mapped_column(Date)
    user_id: Mapped[int] = mapped_column(Integer, ForeignKey("user.id"))
    # snapshot of user settings at diary creation time — intentionally decoupled
    # from UserSettings so historical goals don't change when settings are updated
    protein_goal: Mapped[float]
    carb_goal: Mapped[float]
    fat_goal: Mapped[float]
    fiber_goal: Mapped[float]
    calories_goal: Mapped[float]

    @property
    def calories(self) -> float:
        return sum(meal.calories for meal in self.meals)

    @property
    def protein(self) -> float:
        return sum(meal.protein for meal in self.meals)

    @property
    def carb(self) -> float:
        return sum(meal.carb for meal in self.meals)

    @property
    def fat(self) -> float:
        return sum(meal.fat for meal in self.meals)

    @property
    def fiber(self) -> float:
        return sum(meal.fiber for meal in self.meals)