<?php

declare(strict_types=1);

namespace app\miniapi\http;

final class Pagination
{
    public readonly int $page;
    public readonly int $pageSize;

    public function __construct(array $query)
    {
        $this->page = Input::integer($query['page'] ?? 1, 'page', 1, 1000000);
        $this->pageSize = Input::integer($query['page_size'] ?? config('mini_api.default_page_size', 20), 'page_size', 1, (int) config('mini_api.max_page_size', 100));
        if (config('mini_protection.enabled', false) && $this->offset() >= (int) config('mini_protection.max_list_offset', 10000)) {
            throw new \app\miniapi\exception\ApiException(42201, '查询范围过大，请缩小筛选范围', 422, ['page' => '超出允许的分页查询范围']);
        }
    }

    public function offset(): int
    {
        return ($this->page - 1) * $this->pageSize;
    }

    public function result(array $items, int $total): array
    {
        return [
            'items' => array_values($items),
            'total' => $total,
            'page' => $this->page,
            'page_size' => $this->pageSize,
            'has_more' => $this->offset() + count($items) < $total,
        ];
    }
}