math_cms/app/Models/Textbook.php

<?php

namespace App\Models;

use Illuminate\Database\Eloquent\Model;

class Textbook extends Model
{
    protected $table = 'textbooks';

    protected $fillable = [
        'series_id',
        'stage',
        'schooling_system',
        'grade',
        'semester',
        'naming_scheme',
        'track',
        'module_type',
        'volume_no',
        'legacy_code',
        'curriculum_standard_year',
        'curriculum_revision_year',
        'approval_authority',
        'approval_year',
        'edition_label',
        'official_title',
        'display_title',
        'aliases',
        'isbn',
        'cover_path',
        'status',
        'sort_order',
        'meta',
    ];

    protected $casts = [
        // 移除 array cast，直接使用 JSON 字符串
    ];

    public function series()
    {
        return $this->belongsTo(TextbookSeries::class);
    }

    public function catalogs()
    {
        return $this->hasMany(TextbookCatalog::class);
    }
}