【laralve】访问器的灵活使用

<?php
namespace App\Models;
use Illuminate\Database\Eloquent\Model;
/**
 * 商品分类
 */
class GoodsCategory extends Model
{
    protected  $fillable = ['name', 'category_image'];
    protected $appends = ['levels'];
    public function parent()
    {
        //反向关联
        return $this->belongsTo(GoodsCategory::class);
    }
    public function children() {
        //一对多
        return $this->hasMany(GoodsCategory::class, 'parent_id');
    }
    //定义一个访问器，获取所有祖先类目的ID值
    public function getPossessIdsAttribute()
    {
        //array_filter 将数组中的空值移除
        return array_filter(explode('-', trim($this->possess, '-')));
    }
    //定义一个访问器，获取祖先类目并按层级排序
    public function getAncestorsAttribute()
    {
        return GoodsCategory::query()
            ->whereIn('id', $this->possess_ids)
            //按层级排序
            ->orderBy('level')->get();
    }
    //定义一个访问器，获取以 - 为分隔的所有祖先类目的名称以及当前类目的名称
    public function getFullNameAttribute()
    {
        return $this->ancestors //获取所有祖先类
            ->pluck('name') //获取祖先类目的name 字段为一个数组
            ->push($this->name)//获取当前类目的 name 字段加到数组的末尾
            ->implode(' - '); //用 - 符合将数组的值组成一个字符串
    }
    public function getLevelsAttribute($value) {
        $data = [
            '0' => '根目录',
            '1' => '二级',
            '2' => '三级',
        ];
        // return (is_null($value)) ? $data : $data[$value];
        return (is_null($this->attributes['level'])) ? $data : $data[$this->attributes['level']];
    }
    /**
     * 测试方法
     * @return [type] [description]
     */
    public function test() {
        $category = GoodsCategory::where('id', 105)->first();
        $data = $category->ancestors->toArray();
        return $data;
    }
}