<?php

declare(strict_types=1);

namespace BattleForge\Application;

final class ImageUploadService
{
    public function __construct(
        private readonly string $userToken,
        private readonly string $uploadsRoot,
    ) {
    }

    public function store(string $tempPath, string $declaredMime): string
    {
        $validated = ImageValidator::validate($tempPath, $declaredMime);

        $namespace = $this->uploadsRoot . '/' . $this->userToken;
        if (!is_dir($namespace)) {
            mkdir($namespace, 0700, true);
        }

        $hash = bin2hex(random_bytes(16));
        $filename = $hash . '.' . $validated->extension;
        $destination = $namespace . '/' . $filename;

        if (!rename($tempPath, $destination)) {
            throw new InvalidImageException("Could not move upload to {$destination}.");
        }

        // Lock the file down: the namespace is already 0700; tighten the
        // file itself to 0600 in case the server's umask is permissive.
        chmod($destination, 0600);

        return '/assets/uploads/' . $this->userToken . '/' . $filename;
    }
}