"""项目成本汇总模型

存储项目的成本计算结果
"""

from datetime import datetime
from decimal import Decimal
from typing import TYPE_CHECKING

from sqlalchemy import BigInteger, DateTime, DECIMAL, ForeignKey
from sqlalchemy.orm import Mapped, mapped_column, relationship

from app.models.base import BaseModel

if TYPE_CHECKING:
    from app.models.project import Project


class ProjectCostSummary(BaseModel):
    """项目成本汇总表"""
    
    __tablename__ = "project_cost_summaries"
    
    project_id: Mapped[int] = mapped_column(
        BigInteger,
        ForeignKey("projects.id", ondelete="CASCADE"),
        nullable=False,
        unique=True,
        index=True,
        comment="项目ID"
    )
    material_cost: Mapped[Decimal] = mapped_column(
        DECIMAL(12, 2),
        nullable=False,
        default=0,
        comment="耗材成本"
    )
    equipment_cost: Mapped[Decimal] = mapped_column(
        DECIMAL(12, 2),
        nullable=False,
        default=0,
        comment="设备折旧成本"
    )
    labor_cost: Mapped[Decimal] = mapped_column(
        DECIMAL(12, 2),
        nullable=False,
        default=0,
        comment="人工成本"
    )
    fixed_cost_allocation: Mapped[Decimal] = mapped_column(
        DECIMAL(12, 2),
        nullable=False,
        default=0,
        comment="固定成本分摊"
    )
    total_cost: Mapped[Decimal] = mapped_column(
        DECIMAL(12, 2),
        nullable=False,
        default=0,
        comment="总成本（最低成本线）"
    )
    calculated_at: Mapped[datetime] = mapped_column(
        DateTime,
        nullable=False,
        comment="计算时间"
    )
    
    # 关系
    project: Mapped["Project"] = relationship(
        "Project",
        back_populates="cost_summary"
    )