cxxfds-service/app/Models/ApplicationFile.php

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\BelongsTo;
use Illuminate\Support\Facades\Storage;
use Illuminate\Support\Facades\URL;

class ApplicationFile extends Model
{
    protected $fillable = [
        'application_id',
        'kind',
        'disk',
        'path',
        'original_name',
        'size',
        'mime',
    ];

    public function application(): BelongsTo
    {
        return $this->belongsTo(Application::class);
    }

    public function publicUrl(): string
    {
        $u = Storage::disk($this->disk)->url($this->path);

        return preg_replace('#([^:])//+#', '$1/', $u) ?? $u;
    }

    /**
     * 浏览器下载/「另存为」显示名：优先用户上传时的原始文件名，必要时按存储路径补全扩展名（避免无后缀时落到随机 storage 名）。
     */
    public function clientDownloadName(): string
    {
        $raw = $this->original_name !== null && trim($this->original_name) !== ''
            ? basename(str_replace(['\\', '/'], '_', $this->original_name))
            : '';
        $storageExt = strtolower((string) pathinfo($this->path, PATHINFO_EXTENSION));

        if ($raw !== '') {
            $baseExt = strtolower((string) pathinfo($raw, PATHINFO_EXTENSION));
            if ($storageExt !== '' && $baseExt === '') {
                $raw .= '.'.$storageExt;
            }

            return $raw;
        }

        return $storageExt !== '' ? '附件.'.$storageExt : '附件';
    }

    /**
     * PDF/图片在浏览器内联预览，其余类型用 attachment 以触发「保存为」时使用 clientDownloadName，避免地址栏/标题仍显示 storage 随机名。
     */
    public function preferredStreamDisposition(): string
    {
        $mime = strtolower((string) ($this->mime ?? ''));
        if ($mime !== '') {
            if (str_starts_with($mime, 'image/') || $mime === 'application/pdf') {
                return 'inline';
            }

            return 'attachment';
        }

        $ext = strtolower((string) pathinfo($this->path, PATHINFO_EXTENSION));
        if ($ext === 'pdf') {
            return 'inline';
        }

        return 'attachment';
    }

    /**
     * 选手端「预览」用 URL：走 web 签名路由直出文件，不依赖 public/storage 符号链接（生产环境未 link 时 /storage/... 会 404）。
     */
    public function participantPreviewSignedUrl(int $ttlSeconds = 172800): string
    {
        $u = URL::temporarySignedRoute(
            'participant.application-file.download',
            now()->addSeconds(max(60, $ttlSeconds)),
            ['file' => $this->id],
        );

        return preg_replace('#([^:])//+#', '$1/', $u) ?? $u;
    }
}