result = {'widgettype': 'Message', 'options': {'title': 'Error', 'message': 'Invalid', 'type': 'error'}}

try:
    product_id = params_kw.get('product_id', '')
    if not product_id:
        raise ValueError('缺少产品ID')

    userid = await get_user()
    if not userid:
        raise ValueError('请先登录')

    userorgid = await get_userorgid()
    dbname = get_module_dbname('product_management')

    async with DBPools().sqlorContext(dbname) as sor:
        recs = await sor.sqlExe(
            "SELECT * FROM product WHERE id = ${id}$ AND status = '1'",
            {'id': product_id}
        )
        if not recs:
            raise ValueError('产品不存在或已下架')

        p = recs[0]
        order_id = getID()
        now = timestampstr()
        order = {
            'id': order_id,
            'product_id': p.id,
            'product_code': p.product_code or '',
            'product_name': p.product_name or '',
            'buyer_id': userid,
            'buyer_org_id': userorgid or '0',
            'quantity': 1,
            'unit_price': float(p.price or 0),
            'total_price': float(p.price or 0),
            'currency': p.currency or 'CNY',
            'status': 'pending',
            'purchase_data': '{}',
            'created_at': now,
            'updated_at': now
        }
        await sor.C('purchase_orders', order)

    result = {
        'widgettype': 'Message',
        'options': {
            'title': '购买成功',
            'message': f"已提交购买订单: {p.product_name}，订单号: {order_id}",
            'type': 'success',
            'timeout': 5
        }
    }
except Exception as e:
    result['options'] = {'title': '购买失败', 'message': str(e), 'type': 'error', 'timeout': 5}

return json.dumps(result, ensure_ascii=False)