404 Not Found

<?php

declare(strict_types=1);

namespace App\Core\Routing;

use App\Core\Http\Request;
use App\Core\Http\Response;

class Router
{
    private array $routes = [];
    private $notFoundHandler = null;

    public function get(string $path, array|callable $handler): self
    {
        $this->addRoute('GET', $path, $handler);
        return $this;
    }

    public function post(string $path, array|callable $handler): self
    {
        $this->addRoute('POST', $path, $handler);
        return $this;
    }

    public function put(string $path, array|callable $handler): self
    {
        $this->addRoute('PUT', $path, $handler);
        return $this;
    }

    public function delete(string $path, array|callable $handler): self
    {
        $this->addRoute('DELETE', $path, $handler);
        return $this;
    }

    public function any(string $path, array|callable $handler): self
    {
        foreach (['GET', 'POST', 'PUT', 'DELETE', 'PATCH'] as $method) {
            $this->addRoute($method, $path, $handler);
        }
        return $this;
    }

    public function setNotFound(callable $handler): void
    {
        $this->notFoundHandler = $handler;
    }

    private function addRoute(string $method, string $path, array|callable $handler): void
    {
        // Normalize path
        $path = '/' . trim($path, '/');
        if ($path === '//') {
            $path = '/';
        }

        // Convert {param} to regex pattern (?P<param>[^/]+)
        $pattern = preg_replace('/\{([a-zA-Z0-9_]+)\}/', '(?P<$1>[^/]+)', $path);
        $regex = '#^' . $pattern . '$#';

        $this->routes[] = [
            'method' => strtoupper($method),
            'path' => $path,
            'regex' => $regex,
            'handler' => $handler,
        ];
    }

    public function dispatch(Request $request, Response $response): Response
    {
        $method = $request->getMethod();
        $path = $request->getPath();

        foreach ($this->routes as $route) {
            if ($route['method'] !== $method) {
                continue;
            }

            if (preg_match($route['regex'], $path, $matches)) {
                // Extract named matches for params
                $params = [];
                foreach ($matches as $key => $value) {
                    if (is_string($key)) {
                        $params[$key] = $value;
                    }
                }

                $handler = $route['handler'];

                if (is_callable($handler)) {
                    $result = call_user_func($handler, $request, $response, $params);
                } elseif (is_array($handler) && count($handler) === 2) {
                    [$controllerClass, $action] = $handler;
                    $controller = new $controllerClass();
                    $result = call_user_func([$controller, $action], $request, $response, $params);
                } else {
                    throw new \RuntimeException('Invalid route handler specified.');
                }

                if ($result instanceof Response) {
                    return $result;
                }

                if (is_string($result)) {
                    return $response->setContent($result);
                }

                return $response;
            }
        }

        // 404 Not Found
        if ($this->notFoundHandler) {
            $result = call_user_func($this->notFoundHandler, $request, $response);
            if ($result instanceof Response) {
                return $result;
            }
            return $response->setStatusCode(404)->setContent((string)$result);
        }

        return $response->setStatusCode(404)->setContent('<h1>404 Not Found</h1><p>The requested route does not exist.</p>');
    }
}