<?php

namespace Core\Routing;

use Core\Exceptions\ExceptionHandler;
use Core\Exceptions\Exceptions\NotFoundHttpException;
use Core\Http\Request;
use Core\Http\View\Engine;
use Exception;

class RouteDispatcher
{
    /**
     * Current request instance
     *
     * @var \Core\Http\Request
     */
    private Request $request;

    /**
     * Collection of all routes
     *
     * @var array
     */
    private array $routeCollection;

    /**
     * Dispatch the router dispatcher
     *
     * @param \Core\Http\Request $request
     * @param array              $routeCollection
     * @return void
     */
    public function dispatch(Request $request, array $routeCollection): void
    {
        $this->request         = $request;
        $this->routeCollection = $routeCollection;

        try {
            $route      = $this->findMatchingRoute();
            $controller = $this->instantiateController($route['controller']);
            $action     = $this->validateActionExists($controller, $route['action']);
            $params     = $this->resolveParameters($controller, $action, $route['params'] ?? []);

            $this->executeAction($controller, $action, $params);
        } catch (NotFoundHttpException $e) {
            $this->handleException($e, 404, 'page not found');
        } catch (Exception $e) {
            $this->handleException($e, 500, 'something went wrong');
        }
    }

    /**
     * Locate a matching route for the incoming request.
     *
     * @return array
     * @throws \Core\Exceptions\Exceptions\NotFoundHttpException
     */
    private function findMatchingRoute(): array
    {
        $url    = $this->request->url();
        $method = $this->request->method();

        $route = RouteCollection::find($method, $url);
        if ($route) {
            return $route;
        }

        throw new NotFoundHttpException(sprintf("No route found for: %s", $url));
    }

    /**
     * Create an instance of the requested controller.
     *
     * @param string $controllerName
     * @return object
     * @throws \Core\Exceptions\Exceptions\NotFoundHttpException
     */
    private function instantiateController(string $controllerName): object
    {
        if (!class_exists($controllerName)) {
            throw new NotFoundHttpException(sprintf("Controller '%s' missing", $controllerName));
        }

        return new $controllerName($this->request);
    }

    /**
     * Validate that the action exists in the controller.
     *
     * @param object $controller
     * @param string $actionName
     * @return string
     * @throws \Core\Exceptions\Exceptions\NotFoundHttpException
     */
    private function validateActionExists(object $controller, string $actionName): string
    {
        if (!method_exists($controller, $actionName)) {
            throw new NotFoundHttpException(sprintf("Method '%s' not found on '%s'", $actionName, get_class($controller)));
        }

        return $actionName;
    }

    /**
     * Validate and resolve parameters for the controller action.
     *
     * @param object $controller
     * @param string $action
     * @param array  $params
     * @return array
     * @throws \Exception
     */
    private function resolveParameters(object $controller, string $action, array $params): array
    {
        return RouteValidator::resolve($controller, $action, $params);
    }

    /**
     * Execute the resolved action on the controller with validated parameters.
     *
     * @param object $controller
     * @param string $action
     * @param array  $params
     * @return void
     */
    private function executeAction(object $controller, string $action, array $params): void
    {
        $response = $controller->$action(...$params);

        if ($response instanceof Render) {
            $response->render();
        }
    }

    /**
     * Handle exceptions gracefully.
     *
     * @param Exception $e
     * @param int       $statusCode
     * @param string    $message
     * @return void
     */
    private function handleException(Exception $e, int $statusCode, string $message): void
    {
        if (env('debug')) {
            ExceptionHandler::catchOne($e);
        }

        http_response_code($statusCode);
        echo $message;
    }
}