<?php

declare (strict_types=1);
namespace HelpGent\Invoker;

use Closure;
use HelpGent\Invoker\Exception\NotCallableException;
use HelpGent\Psr\Container\ContainerInterface;
use HelpGent\Psr\Container\NotFoundExceptionInterface;
use ReflectionException;
use ReflectionMethod;
/**
 * Resolves a callable from a container.
 */
class CallableResolver
{
    /** @var ContainerInterface */
    private $container;
    public function __construct(ContainerInterface $container)
    {
        $this->container = $container;
    }
    /**
     * Resolve the given callable into a real PHP callable.
     *
     * @param callable|string|array $callable
     * @return callable Real PHP callable.
     * @throws NotCallableException|ReflectionException
     */
    public function resolve($callable) : callable
    {
        if (\is_string($callable) && \strpos($callable, '::') !== \false) {
            $callable = \explode('::', $callable, 2);
        }
        $callable = $this->resolveFromContainer($callable);
        if (!\is_callable($callable)) {
            throw NotCallableException::fromInvalidCallable($callable, \true);
        }
        return $callable;
    }
    /**
     * @param callable|string|array $callable
     * @return callable|mixed
     * @throws NotCallableException|ReflectionException
     */
    private function resolveFromContainer($callable)
    {
        // Shortcut for a very common use case
        if ($callable instanceof Closure) {
            return $callable;
        }
        // If it's already a callable there is nothing to do
        if (\is_callable($callable)) {
            // TODO with PHP 8 that should not be necessary to check this anymore
            if (!$this->isStaticCallToNonStaticMethod($callable)) {
                return $callable;
            }
        }
        // The callable is a container entry name
        if (\is_string($callable)) {
            try {
                return $this->container->get($callable);
            } catch (NotFoundExceptionInterface $e) {
                if ($this->container->has($callable)) {
                    throw $e;
                }
                throw NotCallableException::fromInvalidCallable($callable, \true);
            }
        }
        // The callable is an array whose first item is a container entry name
        // e.g. ['some-container-entry', 'methodToCall']
        if (\is_array($callable) && \is_string($callable[0])) {
            try {
                // Replace the container entry name by the actual object
                $callable[0] = $this->container->get($callable[0]);
                return $callable;
            } catch (NotFoundExceptionInterface $e) {
                if ($this->container->has($callable[0])) {
                    throw $e;
                }
                throw new NotCallableException(\sprintf('Cannot call %s() on %s because it is not a class nor a valid container entry', $callable[1], $callable[0]));
            }
        }
        // Unrecognized stuff, we let it fail later
        return $callable;
    }
    /**
     * Check if the callable represents a static call to a non-static method.
     *
     * @param mixed $callable
     * @throws ReflectionException
     */
    private function isStaticCallToNonStaticMethod($callable) : bool
    {
        if (\is_array($callable) && \is_string($callable[0])) {
            [$class, $method] = $callable;
            if (!\method_exists($class, $method)) {
                return \false;
            }
            $reflection = new ReflectionMethod($class, $method);
            return !$reflection->isStatic();
        }
        return \false;
    }
}
