<?php

namespace NoccyLabs\React\CommandBus;

use ReflectionFunction;
use ReflectionNamedType;
use React\Promise\Deferred;
use React\Promise\Promise;
use React\Promise\PromiseInterface;

/**
 *
 */
class Command
{
    /** @var string $name The command name */
    private string $name;

    /** @var callable $handler The handler */
    private $handler;

    public function __construct(string $name, callable $handler)
    {
        $this->name = $name;
        $this->handler = $handler;
    }

    public function getName(): string
    {
        return $this->name;
    }

    public function call(Context $context): PromiseInterface
    {
        return new Promise(function (callable $resolve) use ($context) {
            $args = $context->toMethodParameters($this->handler);
            $resolve(call_user_func($this->handler, ...$args));
            //$resolve(call_user_func($this->handler, $context));
            return;
        });
    }

    public function parameters(): array
    {
        $refl = new ReflectionFunction($this->handler);
        $args = [];

        foreach ($refl->getParameters() as $parameter) {
            $name = $parameter->getName();
            $type = null;
            if (!$parameter->hasType()) {
                $type = 'any';
            } else {
                $type = $parameter->getType();
                if ($type instanceof ReflectionNamedType && $type->isBuiltin()) {
                    $type = ($type->allowsNull() ? "?" : "") . $type->getName();
                } else {
                    $type = null;
                }
            }
            
            if ($parameter->isDefaultValueAvailable()) $type = "{$type}=".\json_encode($parameter->getDefaultValue(),\JSON_UNESCAPED_SLASHES);
            if ($type !== null) $args[$name] = $type;
        }

        return $args;
    }

}