import json
from app.extensions import db, beijing_time
from datetime import datetime


class PurchaseRequest(db.Model):
    """
    采购申请表
    """
    __tablename__ = 'purchase_request'

    id = db.Column(db.Integer, primary_key=True)
    request_no = db.Column(db.String(100), unique=True, nullable=False, index=True)
    name = db.Column(db.String(255), nullable=False, comment='采购名称')
    spec_model = db.Column(db.String(255), comment='规格型号')
    quantity = db.Column(db.Numeric(19, 4), nullable=False, comment='采购数量')
    purchase_date = db.Column(db.Date, nullable=False, comment='采购时间')
    supplier_link = db.Column(db.String(500), comment='商家地址链接')
    remark = db.Column(db.Text, comment='备注信息')
    images = db.Column(db.Text, comment='图片列表JSON')
    unit_price = db.Column(db.Numeric(19, 4), default=0, comment='单价')
    total_price = db.Column(db.Numeric(19, 4), default=0, comment='总价')
    status = db.Column(db.Integer, default=0, nullable=False)
    requester_id = db.Column(db.Integer, nullable=False, index=True)
    approver_id = db.Column(db.Integer, index=True)
    approved_at = db.Column(db.DateTime)
    reject_reason = db.Column(db.Text)
    created_at = db.Column(db.DateTime, default=beijing_time, nullable=False)
    updated_at = db.Column(db.DateTime, default=beijing_time, onupdate=beijing_time, nullable=False)

    def _safe_parse_json(self, value):
        if value is None:
            return []
        if isinstance(value, (list, dict)):
            return value
        if isinstance(value, str):
            val = value.strip()
            if not val:
                return []
            try:
                parsed = json.loads(val)
                return parsed if isinstance(parsed, list) else []
            except Exception:
                return []
        return []

    def get_images(self):
        return self._safe_parse_json(self.images)

    def set_images(self, image_list):
        self.images = json.dumps(image_list, ensure_ascii=False) if image_list else '[]'

    def _get_user_name(self, user_id):
        if not user_id:
            return ""
        from app.models.system import SysUser
        try:
            user = db.session.get(SysUser, user_id)
            return user.username if user else f"未知用户({user_id})"
        except Exception:
            return f"用户({user_id})"

    def to_dict(self):
        return {
            'id': self.id,
            'request_no': self.request_no,
            'name': self.name,
            'spec_model': self.spec_model or '',
            'quantity': float(self.quantity) if self.quantity else 0,
            'purchase_date': self.purchase_date.strftime('%Y-%m-%d') if self.purchase_date else None,
            'supplier_link': self.supplier_link or '',
            'remark': self.remark or '',
            'images': self.get_images(),
            'unit_price': float(self.unit_price) if self.unit_price else 0,
            'total_price': float(self.total_price) if self.total_price else 0,
            'status': self.status,
            'status_text': ['待审批', '已通过', '已驳回', '已完成'][self.status] if self.status in [0, 1, 2, 3] else '未知',
            'requester_id': self.requester_id,
            'requester_name': self._get_user_name(self.requester_id),
            'approver_id': self.approver_id,
            'approver_name': self._get_user_name(self.approver_id) if self.approver_id else None,
            'approved_at': self.approved_at.strftime('%Y-%m-%d %H:%M:%S') if self.approved_at else None,
            'reject_reason': self.reject_reason or '',
            'created_at': self.created_at.strftime('%Y-%m-%d %H:%M:%S') if self.created_at else None,
            'updated_at': self.updated_at.strftime('%Y-%m-%d %H:%M:%S') if self.updated_at else None,
        }