javascript - How to implement the function of sending shopping coupons (valid for three months) to new users upon registration?

The company now plans to launch the function of new shopping coupons for new users, and the current requirement is
1. The current website shopping coupons have no expiration date and can be used forever.
2. The shopping voucher can be used together with the original shopping voucher and has the same name in the eyes of the customer.
3. During the validity period, the customer will see the total number of shopping coupons (assuming the customer recharges 100, plus the 100 gifted, then the customer will see 200 shopping coupons on their account)
4. The shopping vouchers given by registration expire after three months, and any unused vouchers will be cleared.
5. Shopping vouchers obtained by customers in other ways are also available indefinitely.

Reply content:

The company now plans to launch the function of new shopping coupons for new users, and the current requirement is
1. The current website shopping coupons have no expiration date and can be used forever.
2. The shopping voucher can be used together with the original shopping voucher and has the same name in the eyes of the customer.
3. During the validity period, the customer will see the total number of shopping coupons (assuming the customer recharges 100, plus the 100 gifted, then the customer will see 200 shopping coupons on their account)
4. The shopping vouchers given by registration expire after three months, and any unused vouchers will be cleared.
5. Shopping vouchers obtained by customers in other ways are also available indefinitely.

The database gives a coupon field mark, start time and expiration time, and whether it can be used. A 0 for expiration means it cannot be used, and vice versa

The problem lies in #3, the customer can see that the total amount of the shopping voucher has nothing to do with the need to store the shopping voucher number in the system.

Although it is understandable that other information except the total amount of available coupons is useless, if there is a problem, you still have to tell the customer which coupon change caused the balance change.

The correct answer is that coupons always have an expiration time set. This is the original logic.

It can be divided into recharge shopping coupons and gift shopping coupons. Priority is given to using gift shopping coupons. There is also a place to display expired shopping coupons, just like the coupons on Jingdong Mall

This should be separated. You can give priority to the shopping coupons with the closest validity period. If you don’t separate them, if they expire, the customer will complain because he doesn’t know why he lost 100
1. All shopping coupons have an expiration date and are permanently valid. The same is true for it, which is convenient for display and reading, and also convenient for data design
2. Shopping coupons must also have types

To understand it simply:
1. Shopping vouchers are divided into types, including gift shopping vouchers and recharged shopping vouchers. Recharged shopping vouchers will never expire, while complimentary shopping vouchers will expire;
2. The shopping coupon is designed as a data table. The data table stores the ID, type, creation time, user ID, expiration time, etc. of the shopping coupon. It is specifically designed according to the business logic;
3. Every time you shop, Check the remaining status of the shopping coupons, and use the free shopping coupons first. If the free shopping coupons have expired, use the recharge shopping coupons
In short, according to your business design, shopping coupons need to be distinguished by type, otherwise Easy to get confused