<?php

declare(strict_types=1);

namespace App\Models\Concerns;

use App\Models\Media;
use Illuminate\Database\Eloquent\Model;
use Illuminate\Database\Eloquent\Relations\BelongsTo;

/**
 * Keeps the media table in step with the image paths a record holds.
 *
 * The panel still uploads a file and stores its path, exactly as before; this
 * is what turns that path into something the frontend can render properly.
 * Models declare which of their attributes are images and expose an ordinary
 * `belongsTo` relation for each, so a listing can eager-load them instead of
 * asking once per row.
 */
trait HasImages
{
    /**
     * Attributes holding the path of an uploaded file.
     *
     * @return array<int, string>
     */
    abstract public function imageAttributes(): array;

    public static function bootHasImages(): void
    {
        static::saved(function (Model $model): void {
            foreach ($model->imageAttributes() as $attribute) {
                // Only on the way in or on a change: an unrelated save must
                // not queue work for an image nobody touched.
                if ($model->wasChanged($attribute) || $model->wasRecentlyCreated) {
                    Media::for($model->getAttribute($attribute));
                }
            }
        });
    }

    /**
     * Relation definition shared by every image attribute.
     *
     * The join is on the stored path rather than on an id, because the file is
     * the identity: two records pointing at one upload share its dimensions
     * and its derived versions instead of each deriving them again.
     */
    protected function imageRelation(string $attribute): BelongsTo
    {
        return $this->belongsTo(Media::class, $attribute, 'path')
            ->where('media.disk', (string) config('media.disk', 'public'));
    }
}