UNIT3D-Community-Edition/app/Models/PrivateMessage.php

<?php
/**
 * NOTICE OF LICENSE.
 *
 * UNIT3D Community Edition is open-sourced software licensed under the GNU Affero General Public License v3.0
 * The details is bundled with this project in the file LICENSE.txt.
 *
 * @project    UNIT3D Community Edition
 *
 * @author     HDVinnie <hdinnovations@protonmail.com>
 * @license    https://www.gnu.org/licenses/agpl-3.0.en.html/ GNU Affero General Public License v3.0
 */

namespace App\Models;

use App\Helpers\Bbcode;
use App\Helpers\Linkify;
use Illuminate\Database\Eloquent\Factories\HasFactory;
use Illuminate\Database\Eloquent\Model;
use voku\helper\AntiXSS;

class PrivateMessage extends Model
{
    use HasFactory;

    /**
     * The attributes that aren't mass assignable.
     *
     * @var string[]
     */
    protected $guarded = ['id', 'created_at', 'updated_at'];

    /**
     * Belongs To A User.
     *
     * @return \Illuminate\Database\Eloquent\Relations\BelongsTo<User, self>
     */
    public function sender(): \Illuminate\Database\Eloquent\Relations\BelongsTo
    {
        return $this->belongsTo(User::class, 'sender_id')->withDefault([
            'username' => 'System',
            'id'       => '1',
        ]);
    }

    /**
     * Belongs To A User.
     *
     * @return \Illuminate\Database\Eloquent\Relations\BelongsTo<User, self>
     */
    public function receiver(): \Illuminate\Database\Eloquent\Relations\BelongsTo
    {
        return $this->belongsTo(User::class, 'receiver_id')->withDefault([
            'username' => 'System',
            'id'       => '1',
        ]);
    }

    /**
     * Has a reply.
     *
     * @return \Illuminate\Database\Eloquent\Relations\HasOne<PrivateMessage>
     */
    public function reply(): \Illuminate\Database\Eloquent\Relations\HasOne
    {
        return $this->HasOne(PrivateMessage::class, 'related_to');
    }

    /**
     * Has a reply.
     *
     * @return \Illuminate\Database\Eloquent\Relations\HasOne<PrivateMessage>
     */
    public function replyRecursive(): \Illuminate\Database\Eloquent\Relations\HasOne
    {
        return $this->reply()->with('replyRecursive');
    }

    /**
     * Set The PM Message After Its Been Purified.
     */
    public function setMessageAttribute(string $value): void
    {
        $this->attributes['message'] = htmlspecialchars((new AntiXSS())->xss_clean($value), ENT_NOQUOTES);
    }

    /**
     * Parse Content And Return Valid HTML.
     */
    public function getMessageHtml(): string
    {
        $bbcode = new Bbcode();

        return (new Linkify())->linky($bbcode->parse($this->message));
    }
}