<?php
final class Pagination {
    public static function calculate(int $count,int $size,int $current,string $action=''): array {
        $count=max(0,$count);$size=max(1,min(100,$size));$last=max(1,(int)ceil($count/$size));
        $page=match($action){'first'=>1,'previous'=>$current-1,'next'=>$current+1,'last'=>$last,default=>$current};
        $page=max(1,min($last,$page));$offset=($page-1)*$size;
        return ['size'=>$size,'page'=>$page,'offset'=>$offset,'start'=>$count?$offset+1:0,'end'=>min($count,$offset+$size)];
    }
    public static function session(string $scope,int $count,int $size,string $action=''): array {
        if(!is_array($_SESSION[Base::PAGINATION_PAGE]??null))$_SESSION[Base::PAGINATION_PAGE]=[];
        $result=self::calculate($count,$size,(int)($_SESSION[Base::PAGINATION_PAGE][$scope]??1),$action);
        $_SESSION[Base::PAGINATION_PAGE][$scope]=$result['page'];return $result;
    }
}