<?php

namespace App\Traits;

use Auth;
use App\Models\Change;

trait TrackChanges
{
    public static function bootTrackChanges()
    {
        static::updated(function ($object) {
            $changes = [];
            $now = date('Y-m-d H:i:s');
            foreach ($object->getDirty() as $attribute => $value) {
                //only store updates of non guarded stuff, i.e. attributes that are mass assignable
                if (!in_array($attribute, $object->guarded)) {
                    //get the old value
                    $original = $object->getOriginal($attribute);
                    // skip trivial changes
                    if ($original !== $object->$attribute) {
                        $changes[] = [
                            'object_type' => self::class,
                            'object_id' => $object->id,
                            'attribute' => $attribute,
                            'old_value' => $original,
                            'new_value' => $object->$attribute, // leave this out if you like normalized tables
                            'actor_id' => Auth::check() ? Auth::user()->id : null,
                            'created_at' => $now,
                            'updated_at' => $now,
                        ];
                    }
                }
            }
            // bulk insert
            Change::insert($changes);
        });
    }

    public function changes()
    {
        return $this->hasMany(Change::class, 'object_id')->where('object_type', static::class);
    }
}