"""AI 抽取的待办（待看/待读/待办）。"""
from __future__ import annotations

from datetime import datetime
from enum import Enum

from sqlalchemy import DateTime, ForeignKey, Index, Integer, String, Text, func
from sqlalchemy.orm import Mapped, mapped_column, relationship

from app.core.db import Base


class TodoStatus(str, Enum):
    """待办状态。"""

    PENDING = "pending"
    DOING = "doing"
    DONE = "done"
    DROPPED = "dropped"


class Todo(Base):
    """AI 从截图中抽取的待办项。"""

    __tablename__ = "todos"
    __table_args__ = (
        Index("ix_todos_status", "status"),
        Index("ix_todos_screenshot_id", "screenshot_id"),
    )

    id: Mapped[int] = mapped_column(Integer, primary_key=True, autoincrement=True)
    screenshot_id: Mapped[int] = mapped_column(
        Integer,
        ForeignKey("screenshots.id", ondelete="CASCADE"),
        nullable=False,
    )
    title: Mapped[str] = mapped_column(String(512), nullable=False)
    note: Mapped[str | None] = mapped_column(Text, nullable=True)
    kind: Mapped[str | None] = mapped_column(String(32), nullable=True)  # 待看/待读/待办等
    status: Mapped[str] = mapped_column(String(16), default=TodoStatus.PENDING.value)

    created_at: Mapped[datetime] = mapped_column(
        DateTime, server_default=func.now(), nullable=False
    )
    completed_at: Mapped[datetime | None] = mapped_column(DateTime, nullable=True)

    screenshot = relationship("Screenshot", back_populates="todos")