"""
凭证模型

存储生成的会计凭证
"""

from datetime import datetime
from typing import Optional

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

from app.models.base import BaseModel


class VoucherStatus:
    """凭证状态"""
    DRAFT = "DRAFT"
    CONFIRMED = "CONFIRMED"
    EXPORTED = "EXPORTED"


class Voucher(BaseModel):
    """
    会计凭证模型

    Attributes:
        company_id: 企业ID
        task_id: 对账任务ID
        voucher_number: 凭证编号
        voucher_date: 凭证日期
        period: 会计期间
        summary: 摘要
        entries: 凭证分录（JSON）
        total_debit: 借方合计
        total_credit: 贷方合计
        status: 状态
        confirmed_by: 确认人
        confirmed_at: 确认时间
    """

    __tablename__ = "vouchers"

    company_id: Mapped[int] = mapped_column(Integer, ForeignKey("companies.id"), nullable=False, index=True)
    task_id: Mapped[int] = mapped_column(Integer, ForeignKey("reconciliation_tasks.id"), nullable=False, index=True)

    voucher_number: Mapped[str] = mapped_column(String(50), nullable=False, index=True, comment="凭证编号")
    voucher_date: Mapped[str] = mapped_column(String(20), nullable=False, comment="凭证日期 YYYY-MM-DD")
    period: Mapped[str] = mapped_column(String(20), nullable=False, index=True, comment="会计期间 YYYY-MM")

    summary: Mapped[str] = mapped_column(String(500), nullable=False, comment="摘要")
    entries: Mapped[dict] = mapped_column(JSON, nullable=False, comment="凭证分录列表")

    total_debit: Mapped[float] = mapped_column(Float, nullable=False, default=0.0, comment="借方合计")
    total_credit: Mapped[float] = mapped_column(Float, nullable=False, default=0.0, comment="贷方合计")

    status: Mapped[str] = mapped_column(String(20), nullable=False, default=VoucherStatus.DRAFT, index=True, comment="状态")
    confirmed_by: Mapped[Optional[int]] = mapped_column(Integer, ForeignKey("users.id"), nullable=True)
    confirmed_at: Mapped[Optional[datetime]] = mapped_column(DateTime, nullable=True)

    # 关系
    company = relationship("Company", backref="vouchers")
    task = relationship("ReconciliationTask", backref="vouchers")
    confirmer = relationship("User", foreign_keys=[confirmed_by])

    def __repr__(self) -> str:
        return f"<Voucher(number='{self.voucher_number}', period='{self.period}', status='{self.status}')>"