<?php
class DumpFile
{
    public function __construct($score_id) {
        $this->score_id = $score_id;
    }

    public function show($dir, $ext, $content_type)
    {
        $dirname = sprintf("%s/%d", $dir, floor($this->score_id / 1000) * 1000);
        $filename = sprintf("%s/%d.%s.gz", $dirname, $this->score_id, $ext);

        if (!file_exists($filename)) {
            http_response_code(404);
            return;
        }

        $content_encoding = self::get_content_encoding();

        header("Content-Type: ".$content_type);
        if ($content_encoding !== FALSE) {
            header("Content-Encoding: ".$content_encoding);
            readfile($filename);
        } else {
            readgzfile($filename);
        }
    }

    private static function browser_accept_encodings()
    {
        if (!isset($_SERVER["HTTP_ACCEPT_ENCODING"])) return [];

        return array_map('trim', explode(",", $_SERVER["HTTP_ACCEPT_ENCODING"]));
    }


    private static function get_content_encoding()
    {
        $supported_gzip_encodings = array_intersect(
            self::browser_accept_encodings(),
            ['gzip', 'x-gzip']);

        return count($supported_gzip_encodings) > 0 ?
            $supported_gzip_encodings[0] : FALSE;
    }

}