Псевдонимы пользователей могут быть изменены дважды за три месяца

User nicknames can be changed twice every three months (30 days per month, that is 90 days). If they are not used up twice in three months, the number of changes they have in the next three months will be reset.
Two more times.

CREATE TABLE `users` (
  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,
  ` username `varchar (255) COLLATE utf8mb4_unicode_ci DEFAULT NULL COMMENT'Add Time',
  ` create_time `timestamp NULL DEFAULT NULL COMMENT'add time',
  ` username_update_num`int(10) unsigned NOT NULL DEFAULT'0'COMMENT'Number of User Nickname Modifications',
  PRIMARY KEY (`id`),
) ENGINE = InnoDB DEFAULT CHARSET = utf8 COLLATE = utf8_unicode_ci COMMENT='user master table';

public function handle($request, Closure $next)
    {   
        /**
         * The problem to be solved is that nicknames can be changed twice every three months (90 days).
         * Here's the solution logic
         */
        // Get the user information
        $user = User::where('id', session('uid'))->first();

        // User registration time, create_time uses the timestamp type, so you need to convert it for easy calculation.
        $create_time = strtotime($user->create_time);

        /**
         * Calculations have gone through 90 days since the registration date, that is, several rounds.
         * Current time minus registration time divided by 90 days of seconds = n rounds
         * The resulting value n has very few integers, such as: 1.2; 
         * At this point, it needs to be processed in one way, because as long as it is more than 90 days, even one second more, it needs to enter the next round.
         */
        $n = ceil( round( (time() - $create_time) / (90 * 24 * 3600), 2) );

        /**
         * The data table username_update_num+1 can be modified twice every 90 days.
         * The total number of modifications: How many modifications have been made by users since the registration date?
         * The number of modifications per round: users have two modification opportunities every 90 days
         * The total number of modifications/the number of modifications per round = the number of modifications to the first round; expressed in $a
         */ 
        $a = $user->username_update_num / 2;

        // What's written here is >=, in fact, $a can't be greater than $n.
        if($a >= $n){
            Return response () - > JSON (['code'=> 0,'message'=>'user nickname can only be modified twice in three months, your number of times has run out','data'=>']);
        }else{
            // Number of times that have not been used up in the previous ($n - 1) wheel
            if( ($n - $a) > 1){
                // Change the database manually and fill in the number of modifications. That is to say, before default, every round used up two chances.
                $user->update(['username_update_num' => (($n - 1) * 2)]);
            }
        }
        
        /**
         * Here is the judgement of the required parameters, which has nothing to do with the above logic.
         */
        if(empty($request->post('username'))){
            Return ['code'=> 0,'message'=>'user nickname cannot be empty','data'=>'];
        }
        if($request->post('username') === $user->username){
            Return ['code'=> 0,'message'=>'the modified nickname can't match the original nickname','data'=>'];
        }
        
        return $next($request);
    }

/**
     * User nickname modification (two modifications in three months)
     * 
     * @param \Illuminate\Http\Request
     * @return \Illuminate\Http\Response
     */
    public function usernameUpdate(Request $request)
    {
        $user = User::where('id', session('uid'))->first();

        $data = [
            'username' => $request->post('username'),
            'username_update_num' => $user->username_update_num + 1,
        ];

        if( !$user->update($data) ){
            Return ['code'=> 0,'message'=>'failed to change user nickname','data'=>'];
        }

        Return ['code'=> 1,'message'=>'Successful change of user nickname','data'=>'];
    }