<?php

declare(strict_types=1);

namespace ProxyManager\Factory;

use Closure;
use ProxyManager\Proxy\GhostObjectInterface;
use ProxyManager\ProxyGenerator\LazyLoadingGhostGenerator;
use ProxyManager\ProxyGenerator\ProxyGeneratorInterface;
use ProxyManager\Signature\Exception\InvalidSignatureException;
use ProxyManager\Signature\Exception\MissingSignatureException;

/**
 * Factory responsible of producing ghost instances
 *
 * @author Marco Pivetta <ocramius@gmail.com>
 * @license MIT
 */
class LazyLoadingGhostFactory extends AbstractBaseFactory
{
    /**
     * @var \ProxyManager\ProxyGenerator\LazyLoadingGhostGenerator|null
     */
    private $generator;

    /**
     * {@inheritDoc}
     */
    protected function getGenerator() : ProxyGeneratorInterface
    {
        return $this->generator ?: $this->generator = new LazyLoadingGhostGenerator();
    }

    /**
     * Creates a new lazy proxy instance of the given class with
     * the given initializer
     *
     * Please refer to the following documentation when using this method:
     *
     * @link https://github.com/Ocramius/ProxyManager/blob/master/docs/lazy-loading-ghost-object.md
     *
     * @param string  $className   name of the class to be proxied
     * @param Closure $initializer initializer to be passed to the proxy. The initializer closure should have following
     *                             signature:
     *
     *                             <code>
     *                             $initializer = function (
     *                                 GhostObjectInterface $proxy,
     *                                 string $method,
     *                                 array $parameters,
     *                                 & $initializer,
     *                                 array $properties
     *                             ) {};
     *                             </code>
     *
     *                             Where:
     *                              - $proxy is the proxy instance on which the initializer is acting
     *                              - $method is the name of the method that triggered the lazy initialization
     *                              - $parameters are the parameters that were passed to $method
     *                              - $initializer by-ref initializer - should be assigned null in the initializer body
     *                              - $properties a by-ref map of the properties of the object, indexed by PHP
     *                                            internal property name. Assign values to it to initialize the
     *                                            object state
     *
     * @param mixed[] $proxyOptions a set of options to be used when generating the proxy. Currently supports only
     *                              key "skippedProperties", which allows to skip lazy-loading of some properties.
     *                              "skippedProperties" is a string[], containing a list of properties referenced
     *                              via PHP's internal property name (i.e. "\0ClassName\0propertyName")
     *
     * @throws MissingSignatureException
     * @throws InvalidSignatureException
     * @throws \OutOfBoundsException
     */
    public function createProxy(
        string $className,
        Closure $initializer,
        array $proxyOptions = []
    ) : GhostObjectInterface {
        $proxyClassName = $this->generateProxy($className, $proxyOptions);

        return $proxyClassName::staticProxyConstructor($initializer);
    }
}