"""
字段映射模型

用于存储 AI 识别的字段映射结果
"""

from datetime import datetime
from typing import List, Optional

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

from app.models.base import BaseModel


class FieldMapping(BaseModel):
    """
    字段映射模型

    记录源字段到标准字段的映射关系
    """

    __tablename__ = "field_mappings"

    company_id: Mapped[int] = mapped_column(Integer, ForeignKey("companies.id"), nullable=False, index=True)
    file_id: Mapped[int] = mapped_column(Integer, ForeignKey("uploaded_files.id"), nullable=False, index=True)
    source_field: Mapped[str] = mapped_column(String(100), nullable=False, comment="源字段名")
    standard_field: Mapped[str] = mapped_column(String(100), nullable=False, comment="标准字段名")
    confidence: Mapped[float] = mapped_column(Float, nullable=False, default=0.0, comment="置信度 0-1")
    confirmed: Mapped[bool] = mapped_column(Boolean, nullable=False, default=False, comment="是否已确认")
    confirmed_by: Mapped[Optional[int]] = mapped_column(Integer, ForeignKey("users.id"), nullable=True)
    confirmed_at: Mapped[Optional[datetime]] = mapped_column(DateTime, nullable=True)
    sample_values: Mapped[Optional[dict]] = mapped_column(JSON, nullable=True, comment="样例值")
    reasoning: Mapped[Optional[str]] = mapped_column(Text, nullable=True, comment="AI 判断依据")
    is_skipped: Mapped[bool] = mapped_column(Boolean, nullable=False, default=False, comment="是否跳过")

    # 关系
    company = relationship("Company", back_populates="field_mappings")
    file = relationship("UploadedFile", back_populates="field_mappings")
    confirmed_by_user = relationship("User", foreign_keys=[confirmed_by])

    def __repr__(self) -> str:
        return f"<FieldMapping(source='{self.source_field}' -> standard='{self.standard_field}', confidence={self.confidence})>"