<?php

declare(strict_types=1);

namespace Blax\ReactPhpKernel\Tests;

use Blax\ReactPhpKernel\Contracts\Server;
use Blax\ReactPhpKernel\Kernel;
use Blax\ReactPhpKernel\Tests\Fixtures\RecordingServer;
use PHPUnit\Framework\TestCase;
use React\EventLoop\LoopInterface;
use React\EventLoop\StreamSelectLoop;

final class KernelTest extends TestCase
{
    public function test_uses_the_injected_loop(): void
    {
        $loop = new StreamSelectLoop;

        $this->assertSame($loop, (new Kernel($loop))->loop());
    }

    public function test_boots_and_shuts_down_registered_servers_with_hooks(): void
    {
        $loop = new StreamSelectLoop;
        $kernel = new Kernel($loop);

        $server = new RecordingServer;
        // Stop the kernel on the next tick so run() returns instead of blocking.
        $server->onBoot = fn (LoopInterface $l) => $l->futureTick(fn () => $kernel->stop());

        $bootHook = false;
        $shutdownHook = false;

        $kernel
            ->register($server)
            ->onBoot(function () use (&$bootHook) {
                $bootHook = true;
            })
            ->onShutdown(function () use (&$shutdownHook) {
                $shutdownHook = true;
            })
            ->run();

        $this->assertTrue($server->booted, 'server should have been booted');
        $this->assertTrue($server->wasShutDown, 'server should have been shut down');
        $this->assertTrue($bootHook, 'onBoot hook should have fired');
        $this->assertTrue($shutdownHook, 'onShutdown hook should have fired');
        $this->assertFalse($kernel->isRunning());
    }

    public function test_stop_is_idempotent_and_safe_before_run(): void
    {
        $kernel = new Kernel(new StreamSelectLoop);

        $kernel->stop(); // never ran — must be a harmless no-op
        $kernel->stop();

        $this->assertFalse($kernel->isRunning());
    }

    public function test_a_failing_server_shutdown_does_not_block_the_others(): void
    {
        $loop = new StreamSelectLoop;
        $kernel = new Kernel($loop);

        $throwing = new class implements Server
        {
            public function name(): string
            {
                return 'throwing';
            }

            public function boot(LoopInterface $loop): void {}

            public function shutdown(): void
            {
                throw new \RuntimeException('teardown failed');
            }
        };

        $good = new RecordingServer;
        $good->onBoot = fn (LoopInterface $l) => $l->futureTick(fn () => $kernel->stop());

        $kernel->register($throwing)->register($good)->run();

        $this->assertTrue($good->wasShutDown, 'a throwing teardown must not stop the others');
    }
}