dcat-admin2/src/Traits/BuilderEvents.php

<?php

namespace Dcat\Admin\Traits;

trait BuilderEvents
{
    /**
     * Register a resolving listener.
     *
     * @param callable $callback
     * @param bool $once
     */
    public static function resolving(callable $callback, bool $once = false)
    {
        static::setListeners('builder.resolving', $callback, $once);
    }

    /**
     * @param array ...$params
     */
    protected function callResolving(...$params)
    {
        $this->callBuilderListeners('builder.resolving', ...$params);
    }

    /**
     * Register a composing listener.
     *
     * @param callable $callback
     * @param bool $once
     */
    public static function composing(callable $callback, bool $once = false)
    {
        static::setListeners('builder.composing', $callback, $once);
    }

    /**
     * @param array ...$params
     */
    protected function callComposing(...$params)
    {
        $this->callBuilderListeners('builder.composing', ...$params);
    }

    /**
     * @param $listeners
     * @param array ...$params
     */
    protected function callBuilderListeners($key, ...$params)
    {
        $object = app('admin.object');

        $key = static::formatBuilderEventKey($key);

        $listeners = $object->get($key) ?: [];

        foreach ($listeners as $k => $listener) {
            list($callback, $once) = $listener;

            if ($once) {
                unset($listeners[$k]);
            }

            call_user_func($callback, $this, ...$params);
        }

        $object[$key] = $listeners;
    }

    /**
     * @param string $key
     * @param callable $callback
     * @param bool $once
     */
    protected static function setListeners($key, $callback, $once)
    {
        $object = app('admin.object');

        $key = static::formatBuilderEventKey($key);

        $listeners = $object->get($key) ?: [];

        $listeners[] = [$callback, $once];

        $object[$key] = $listeners;
    }

    protected static function formatBuilderEventKey($key)
    {
        return static::class.'::'.$key;
    }

}