<?php

namespace App\Traits;

//use App\Models\Previewer;
use App\Contracts\Previewable;
use App\Models\Preview;
use Illuminate\Database\Eloquent\Relations\MorphMany;

trait CanPreview
{
    //通用访客功能
    public function preview(Previewable $previewable):preview
    {
        $arr = [
            'previewed_id'   => $this->primaryId(),
            'previewed_type' => get_class(),
        ];
        $result = $this->hasPreviewed($previewable);
        if ($result) {
            $preview = $previewable->previews()->where($arr)->first();
            $preview->increment('num', 1);
        }else {
            $preview = new Preview($arr);
            $previewable->previews()->save($preview);
        }
        return $preview;
    }

    public function hasPreviewed(Previewable $previewable):bool
    {
        $preview = [
            'previewed_id'   => $this->primaryId(),
            'previewed_type' => get_class(),
        ];
        $result = $previewable->previews()->where($preview)->count();
        return $result;
    }

    //用户访问列表（所有服务）
    public function previews(): MorphMany
    {
        return $this->morphMany(Preview::class);
    }
}