Improve fallback error handling

classes/ErrorHandler.php

@@ -0,0 +1,36 @@
+<?php
+
+namespace Alltube;
+
+use Symfony\Component\ErrorHandler\ErrorRenderer\HtmlErrorRenderer;
+use Throwable;
+
+/**
+ * Class ErrorHandler
+ * @package Alltube
+ */
+class ErrorHandler
+{
+
+    /**
+     * Last resort if the error has not been caught by the Slim error handler for some reason.
+     * @param Throwable $e
+     * @return void
+     */
+    public static function handle(Throwable $e)
+    {
+        error_log($e);
+
+        if (class_exists(HtmlErrorRenderer::class)) {
+            // If dev dependencies are loaded, we can use symfony/error-handler.
+            $renderer = new HtmlErrorRenderer(true);
+            $exception = $renderer->render($e);
+
+            http_response_code($exception->getStatusCode());
+            die($exception->getAsString());
+        } else {
+            http_response_code(500);
+            die('Error when starting the app: ' . htmlentities($e->getMessage()));
+        }
+    }
+}

index.php

@@ -6,6 +6,7 @@ use Alltube\ConfigFactory;
 use Alltube\Controller\DownloadController;
 use Alltube\Controller\FrontController;
 use Alltube\Controller\JsonController;
+use Alltube\ErrorHandler;
 use Alltube\LocaleManagerFactory;
 use Alltube\LocaleMiddleware;
 use Alltube\LoggerFactory;
@@ -87,6 +88,5 @@ try {
 
     $app->run();
 } catch (Throwable $e) {
-    // Last resort if the error has not been caught by the error handler for some reason.
-    die('Error when starting the app: ' . htmlentities($e->getMessage()));
+    ErrorHandler::handle($e);
 }