shimmie2/ext/link_scan/main.php

<?php

declare(strict_types=1);

namespace Shimmie2;

class LinkScan extends Extension
{
    public function get_priority(): int
    {
        return 10; // be able to intercept post/list
    }

    public function onPageRequest(PageRequestEvent $event): void
    {
        global $config, $page;

        if ($event->page_matches("post/list") && isset($_GET['search'])) {
            $trigger = $config->get_string("link_scan_trigger", "https?://");
            if (preg_match("#.*{$trigger}.*#", $_GET['search'])) {
                $ids = $this->scan($_GET['search']);
                $page->set_mode(PageMode::REDIRECT);
                $page->set_redirect(search_link(["id=".implode(",", $ids)]));
                $event->stop_processing = true;
            }
        }
    }

    private function scan(string $text): array 
    {
        $ids = [];
        $matches = [];
        preg_match_all("/post\/view\/(\d+)/", $text, $matches);
        foreach($matches[1] as $match) {
            $ids[] = $match;
        }
        preg_match_all("/\b([0-9a-fA-F]{32})\b/", $text, $matches);
        foreach($matches[1] as $match) {
            $ids[] = Image::by_hash($match)->id;
        }
        return array_unique($ids);
    }
}