from datetime import datetime
from app import db
from app.models.version import Version

class Product(db.Model):
    """产品模型"""
    __tablename__ = 'product'

    product_id = db.Column(db.String(32), primary_key=True)
    product_name = db.Column(db.String(64), nullable=False)
    description = db.Column(db.Text, nullable=True)
    status = db.Column(db.Integer, nullable=False, default=1)  # 0=禁用, 1=启用
    create_time = db.Column(db.DateTime, default=datetime.utcnow)
    update_time = db.Column(db.DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)

    # 关联关系
    versions = db.relationship('Version', backref='product', lazy='dynamic', cascade='all, delete-orphan')
    licenses = db.relationship('License', backref='product', lazy='dynamic', cascade='all, delete-orphan')
    devices = db.relationship('Device', backref='product', lazy='dynamic', cascade='all, delete-orphan')
    tickets = db.relationship('Ticket', backref='product', lazy='dynamic', cascade='all, delete-orphan')

    def __init__(self, product_id=None, **kwargs):
        super(Product, self).__init__(**kwargs)
        if product_id:
            self.product_id = product_id
        elif not self.product_id:
            # 自动生成产品ID
            import uuid
            self.product_id = f"PROD_{uuid.uuid4().hex[:8]}".upper()

    def get_stats(self):
        """获取产品统计信息"""
        # 如果已经有缓存的统计信息（来自批量查询），直接使用
        if hasattr(self, '_cached_stats'):
            return self._cached_stats
        
        # 否则执行单个查询（用于单个产品详情等场景）
        total_licenses = self.licenses.count()
        active_licenses = self.licenses.filter_by(status=1).count()
        total_devices = self.devices.filter_by(status=1).count()

        return {
            'total_licenses': total_licenses,
            'active_licenses': active_licenses,
            'total_devices': total_devices,
            'latest_version': self.get_latest_version()
        }

    def get_latest_version(self):
        """获取最新版本"""
        latest_version = self.versions.filter_by(publish_status=1).order_by(
            db.desc(Version.create_time)
        ).first()
        return latest_version.version_num if latest_version else None

    def is_enabled(self):
        """产品是否启用"""
        return self.status == 1

    def to_dict(self, include_stats=False):
        """转换为字典"""
        data = {
            'product_id': self.product_id,
            'product_name': self.product_name,
            'description': self.description,
            'status': self.status,
            'status_name': '启用' if self.status == 1 else '禁用',
            'create_time': self.create_time.strftime('%Y-%m-%d %H:%M:%S'),
            'update_time': self.update_time.strftime('%Y-%m-%d %H:%M:%S')
        }

        if include_stats:
            data.update(self.get_stats())

        return data

    def __repr__(self):
        return f'<Product {self.product_name}>'