from datetime import datetime
from typing import Optional
from sqlalchemy import String, Text, Date, DateTime, ForeignKey, func
from sqlalchemy.orm import Mapped, mapped_column
from app.database import Base


class Task(Base):
    __tablename__ = "tasks"

    id: Mapped[int] = mapped_column(primary_key=True)
    title: Mapped[str] = mapped_column(String(255), nullable=False)
    status: Mapped[str] = mapped_column(String(20), default="todo")  # todo | in_progress | done
    due_date: Mapped[Optional[datetime]] = mapped_column(Date, nullable=True)
    assigned_to: Mapped[Optional[int]] = mapped_column(ForeignKey("users.id", ondelete="SET NULL"), nullable=True)
    parent_id: Mapped[Optional[int]] = mapped_column(ForeignKey("tasks.id", ondelete="CASCADE"), nullable=True)
    created_by: Mapped[int] = mapped_column(ForeignKey("users.id", ondelete="CASCADE"), nullable=False)
    completed_at:      Mapped[Optional[datetime]] = mapped_column(DateTime, nullable=True)
    recurring_task_id: Mapped[Optional[int]]      = mapped_column(ForeignKey("recurring_tasks.id", ondelete="SET NULL"), nullable=True)
    created_at: Mapped[datetime] = mapped_column(DateTime, server_default=func.now())
    updated_at: Mapped[datetime] = mapped_column(DateTime, server_default=func.now(), onupdate=func.now())


class TaskComment(Base):
    __tablename__ = "task_comments"

    id: Mapped[int] = mapped_column(primary_key=True)
    task_id: Mapped[int] = mapped_column(ForeignKey("tasks.id", ondelete="CASCADE"), nullable=False)
    user_id: Mapped[int] = mapped_column(ForeignKey("users.id", ondelete="CASCADE"), nullable=False)
    body: Mapped[str] = mapped_column(Text, nullable=False)
    attachment_path: Mapped[Optional[str]] = mapped_column(String(500), nullable=True)
    created_at: Mapped[datetime] = mapped_column(DateTime, server_default=func.now())