<?php

namespace App\Services;

use RuntimeException;

class EarnDeviceIdentity
{
    public function normalize(string $deviceId): string
    {
        return trim($deviceId);
    }

    public function valid(string $deviceId): bool
    {
        $length = strlen($deviceId);

        return $length >= 4 && $length <= 255 && preg_match('/^[\x20-\x7E]+$/D', $deviceId) === 1;
    }

    public function hash(string $deviceId): string
    {
        $key = (string) config('earn.device.hash_key');
        if (strlen($key) < 32) {
            throw new RuntimeException('Earn device hashing is not configured.');
        }

        return hash_hmac('sha256', $this->normalize($deviceId), $key);
    }

    public function preview(string $deviceId): string
    {
        $normalized = $this->normalize($deviceId);

        if (strlen($normalized) <= 10) {
            return substr($normalized, 0, 2).'••••'.substr($normalized, -2);
        }

        return substr($normalized, 0, 6).'…'.substr($normalized, -5);
    }
}