OrderableCollection.php

<?php

namespace Baril\Orderly;

use Illuminate\Database\Eloquent\Collection as EloquentCollection;

class OrderableCollection extends EloquentCollection
{
    public function saveOrder()
    {
        if ($this->isEmpty()) {
            return $this;
        }

        $instance = $this->first();
        $orderColumn = $instance->getOrderColumn();
        $groupColumn = $instance->getGroupColumn();

        // Check that all items are in the same group:
        if ($groupColumn) {
            foreach ((array) $groupColumn as $column) {
                if ($this->pluck($column)->unique()->count() > 1) {
                    throw new GroupException('All models must be in same group!');
                }
            }
        }

        // Get current positions:
        $positions = $this->pluck($orderColumn)->sort()->all();
        reset($positions);

        // Save the new order:
        $instance->getConnection()->transaction(function () use ($orderColumn, &$positions) {
            $this->values()->each(function ($model) use ($orderColumn, &$positions) {
                // Update the order field without triggering the listeners:
                $model->newQuery()->whereKey($model->getKey())->update([$orderColumn => current($positions)]);
                $model->setAttribute($orderColumn, current($positions));
                next($positions);
            });
        });

        return $this;
    }

    public function setOrder($ids)
    {
        $count = $this->count();
        $ordered = $this->sortBy(function ($item) use ($ids, $count) {
            $index = array_search($item->getKey(), $ids);
            return ($index === false) ? $count + $item->getPosition() : $index;
        });
        return $ordered->saveOrder();
    }
}