# app/models/buy.py
from app.extensions import db
from datetime import datetime


class StockBuy(db.Model):
    """
    采购入库库存表
    对应数据库表: stock_buy
    """
    __tablename__ = 'stock_buy'

    # 主键
    id = db.Column(db.Integer, primary_key=True)

    # 【核心关联】外键关联 material_base 表
    base_id = db.Column(db.Integer, db.ForeignKey('material_base.id'), nullable=False)

    # --- 身份标识 ---
    sku = db.Column(db.String(100))
    in_date = db.Column(db.Date)
    barcode = db.Column(db.String(100))  # 条码
    serial_number = db.Column(db.String(100))  # 序列号
    batch_number = db.Column(db.String(100))  # 批号

    # --- 数量 ---
    in_quantity = db.Column(db.Numeric(19, 4), default=0)
    stock_quantity = db.Column(db.Numeric(19, 4), default=0)
    available_quantity = db.Column(db.Numeric(19, 4), default=0)

    # --- 状态与位置 ---
    status = db.Column(db.String(50))  # 在库/出库/损耗
    inspection_status = db.Column(db.String(50))  # 未检/合格/不合格
    warehouse_location = db.Column(db.String(100))

    # --- 财务与商务 ---
    unit_price = db.Column(db.Numeric(19, 4), default=0)
    total_price = db.Column(db.Numeric(19, 4), default=0)
    currency = db.Column(db.String(20), default='CNY')
    exchange_rate = db.Column(db.Numeric(15, 6), default=1.0)

    supplier_name = db.Column(db.String(255))

    # [关键映射区]：Python属性名 = DB列名
    # 前端传 purchaser -> 存入 buyer_name
    buyer_name = db.Column(db.String(100))

    # 前端传 purchaser_email -> 存入 buyer_email
    buyer_email = db.Column(db.String(100))

    # 前端传 source_link -> 存入 original_link
    original_link = db.Column(db.Text)

    detail_link = db.Column(db.Text)
    arrival_photo = db.Column(db.Text)

    # [这就是报错缺失的字段]，请确保执行了 ALTER TABLE
    remark = db.Column(db.Text)

    # 【关系定义】
    # 建立与 MaterialBase 的关系，方便通过 stock.material 访问基础信息
    material = db.relationship('MaterialBase', back_populates='stock_buys')

    def to_dict(self):
        """
        序列化：将模型转换为字典，主要用于单条查询或内部调用
        列表查询主要依赖 Service 层的手动构建以提高性能
        """
        return {
            'id': self.id,
            'base_id': self.base_id,

            # 级联基础信息 (防止 None 报错)
            'material_name': self.material.name if self.material else '',
            'spec_model': self.material.spec_model if self.material else '',
            'category': self.material.category if self.material else '',
            'unit': self.material.unit if self.material else '',
            'material_type': self.material.material_type if self.material else '',

            # 实体信息
            'sku': self.sku,
            'inbound_date': self.in_date.strftime('%Y-%m-%d') if self.in_date else '',
            'barcode': self.barcode,
            'serial_number': self.serial_number,
            'batch_number': self.batch_number,
            'warehouse_loc': self.warehouse_location,
            'status': self.status,
            'inspection_status': self.inspection_status,
            'remark': self.remark,

            # 数量 (转为float防止json序列化报错)
            'in_quantity': float(self.in_quantity or 0),
            'qty_inbound': float(self.in_quantity or 0),  # 兼容字段
            'stock_quantity': float(self.stock_quantity or 0),
            'qty_stock': float(self.stock_quantity or 0),  # 兼容字段
            'available_quantity': float(self.available_quantity or 0),
            'qty_available': float(self.available_quantity or 0),  # 兼容字段

            # 财务
            'unit_price': float(self.unit_price or 0),
            'total_price': float(self.total_price or 0),
            'currency': self.currency,
            'exchange_rate': float(self.exchange_rate or 1.0),

            # 商务 (字段映射)
            'supplier_name': self.supplier_name,
            'purchaser': self.buyer_name,  # 映射回前端
            'purchaser_email': self.buyer_email,  # 映射回前端
            'source_link': self.original_link,  # 映射回前端
            'detail_link': self.detail_link,
            'arrival_photo': self.arrival_photo
        }