<?php

namespace Kirby\Toolkit;

use Closure;
use Kirby\Filesystem\F;
use ReflectionFunction;

/**
 * A smart extension of Closures with
 * magic dependency injection based on the
 * defined variable names.
 *
 * @package   Kirby Toolkit
 * @author    Bastian Allgeier <bastian@getkirby.com>
 * @link      https://getkirby.com
 * @copyright Bastian Allgeier GmbH
 * @license   https://opensource.org/licenses/MIT
 */
class Controller
{
    protected $function;

    public function __construct(Closure $function)
    {
        $this->function = $function;
    }

    public function arguments(array $data = []): array
    {
        $info = new ReflectionFunction($this->function);
        $args = [];

        foreach ($info->getParameters() as $parameter) {
            $name = $parameter->getName();
            $args[] = $data[$name] ?? null;
        }

        return $args;
    }

    public function call($bind = null, $data = [])
    {
        $args = $this->arguments($data);

        if ($bind === null) {
            return call_user_func($this->function, ...$args);
        }

        return $this->function->call($bind, ...$args);
    }

    public static function load(string $file)
    {
        if (is_file($file) === false) {
            return null;
        }

        $function = F::load($file);

        if (is_a($function, 'Closure') === false) {
            return null;
        }

        return new static($function);
    }
}