"""
儀表板警示 Model
"""
from datetime import datetime
from typing import Optional, TYPE_CHECKING

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

from app.core.database import Base

if TYPE_CHECKING:
    from app.models.employee import Employee
    from app.models.kpi_sheet import KPISheet


class DashboardAlert(Base):
    """儀表板警示"""

    __tablename__ = "KPI_D_alerts"

    id: Mapped[int] = mapped_column(primary_key=True)
    alert_type: Mapped[str] = mapped_column(String(50), nullable=False)
    # deadline_approaching, overdue, weight_invalid
    severity: Mapped[str] = mapped_column(String(20), default="warning")  # info, warning, error
    title: Mapped[str] = mapped_column(String(200), nullable=False)
    description: Mapped[Optional[str]] = mapped_column(Text)
    related_sheet_id: Mapped[Optional[int]] = mapped_column(ForeignKey("KPI_D_sheets.id", ondelete="CASCADE"))
    related_employee_id: Mapped[Optional[int]] = mapped_column(ForeignKey("KPI_D_employees.id"))
    is_resolved: Mapped[bool] = mapped_column(Boolean, default=False)
    resolved_at: Mapped[Optional[datetime]] = mapped_column(DateTime)
    resolved_by: Mapped[Optional[int]] = mapped_column(ForeignKey("KPI_D_employees.id"))
    created_at: Mapped[datetime] = mapped_column(DateTime, default=datetime.utcnow)

    # Relationships
    related_sheet: Mapped[Optional["KPISheet"]] = relationship("KPISheet")
    related_employee: Mapped[Optional["Employee"]] = relationship("Employee", foreign_keys=[related_employee_id])
    resolver: Mapped[Optional["Employee"]] = relationship("Employee", foreign_keys=[resolved_by])

    def __repr__(self) -> str:
        return f"<DashboardAlert id={self.id} type={self.alert_type} severity={self.severity}>"