[TASK] View notice about required configuration in backend module

Classes/Controller/MailqueueModuleController.php

@@ -24,6 +24,7 @@
 namespace CPSIT\Typo3Mailqueue\Controller;
 
 use CPSIT\Typo3Mailqueue\Enums;
+use CPSIT\Typo3Mailqueue\Exception;
 use CPSIT\Typo3Mailqueue\Mail;
 use CPSIT\Typo3Mailqueue\Traits;
 use Psr\Http\Message;
@@ -58,12 +59,14 @@ public function __invoke(Message\ServerRequestInterface $request): Message\Respo
         $template = $this->moduleTemplateFactory->create($request);
         $transport = $this->mailer->getTransport();
         $sendId = $request->getQueryParams()['send'] ?? null;
-        $templateVariables = [];
 
         if ($transport instanceof Mail\Transport\QueueableTransport) {
             $templateVariables = $this->resolveTemplateVariables($transport, $sendId);
         } else {
-            $templateVariables['unsupportedTransport'] = $transport::class;
+            $templateVariables = [
+                'unsupportedTransport' => $this->getTransportFromMailConfiguration(),
+                'typo3Version' => $this->typo3Version->getMajorVersion(),
+            ];
         }
 
         // @todo Remove once support for TYPO3 v11 is dropped
@@ -165,6 +168,32 @@ private function addLinkToConfigurationModule(Backend\Template\ModuleTemplate $t
         $buttonBar->addButton($button);
     }
 
+    /**
+     * @throws Exception\MailTransportIsNotConfigured
+     */
+    private function getTransportFromMailConfiguration(): string
+    {
+        $mailConfiguration = $GLOBALS['TYPO3_CONF_VARS']['MAIL'] ?? null;
+
+        if (!is_array($mailConfiguration)) {
+            throw new Exception\MailTransportIsNotConfigured();
+        }
+
+        $spoolType = $mailConfiguration['transport_spool_type'] ?? null;
+
+        if (is_string($spoolType) && trim($spoolType) !== '') {
+            return $spoolType;
+        }
+
+        $transport = $mailConfiguration['transport'] ?? null;
+
+        if (is_string($transport) && trim($transport) !== '') {
+            return $transport;
+        }
+
+        throw new Exception\MailTransportIsNotConfigured();
+    }
+
     /**
      * @todo Remove once support for TYPO3 v11 is dropped
      *

Classes/Exception/MailTransportIsNotConfigured.php

@@ -0,0 +1,41 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is part of the TYPO3 CMS extension "mailqueue".
+ *
+ * Copyright (C) 2024 Elias Häußler <[email protected]>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+namespace CPSIT\Typo3Mailqueue\Exception;
+
+/**
+ * MailTransportIsNotConfigured
+ *
+ * @author Elias Häußler <[email protected]>
+ * @license GPL-2.0-or-later
+ */
+final class MailTransportIsNotConfigured extends Exception
+{
+    public function __construct()
+    {
+        parent::__construct(
+            'No mail transport is configured. Please provide mail configuration in $GLOBALS[\'TYPO3_CONF_VARS\'][\'MAIL\'].',
+            1709803814,
+        );
+    }
+}

Resources/Private/Language/locallang.xlf

@@ -80,6 +80,16 @@
 				<source>The mail was successfully sent.</source>
 			</trans-unit>
 
+			<trans-unit id="unsupportedTransport.docs.text">
+				<source>Read the %s to learn more about mail spoolers in TYPO3.</source>
+			</trans-unit>
+			<trans-unit id="unsupportedTransport.docs.linkText">
+				<source>official documentation</source>
+			</trans-unit>
+			<trans-unit id="unsupportedTransport.example.header">
+				<source>Example configuration</source>
+			</trans-unit>
+
 			<trans-unit id="modal.failureDetails.header">
 				<source>Transport failure details</source>
 			</trans-unit>

Resources/Private/Partials/List/UnsupportedTransport.html

@@ -0,0 +1,50 @@
+<html xmlns:f="http://typo3.org/ns/TYPO3/CMS/Fluid/ViewHelpers"
+      xmlns:c="http://typo3.org/ns/TYPO3/CMS/Core/ViewHelpers"
+      data-namespace-typo3-fluid="true">
+
+<f:be.infobox state="2"
+              title="{f:translate(key: 'alert.unsupportedTransport.title', extensionName: 'Mailqueue')}"
+              message="{f:translate(key: 'alert.unsupportedTransport.message', arguments: '{0: transport}', extensionName: 'Mailqueue')}"
+/>
+
+<f:variable name="docsLink"><f:spaceless>
+    <a href="https://docs.typo3.org/m/typo3/reference-coreapi/main/en-us/ApiOverview/Mail/Index.html#spooling"
+       target="_blank"
+       rel="noreferrer"
+    >{f:translate(key: 'unsupportedTransport.docs.linkText', extensionName: 'Mailqueue')}</a>
+</f:spaceless></f:variable>
+
+<p>
+    {f:translate(key: 'unsupportedTransport.docs.text', extensionName: 'Mailqueue', arguments: '{0: docsLink}') -> f:format.raw()}
+</p>
+
+<div class="card">
+    <div class="card-header">
+        <div class="card-icon">
+            <c:icon identifier="actions-file-edit" />
+        </div>
+        <div class="card-header-body">
+            <h2 class="card-title">{f:translate(key: 'unsupportedTransport.example.header', extensionName: 'Mailqueue')}</h2>
+        </div>
+    </div>
+    <div class="card-body">
+        <pre><code><f:spaceless>
+$GLOBALS['TYPO3_CONF_VARS']['MAIL']['transport_spool_type'] = 'file';
+$GLOBALS['TYPO3_CONF_VARS']['MAIL']['transport_spool_filepath'] = '/path/to/mailqueue';
+        </f:spaceless></code></pre>
+    </div>
+    <div class="card-footer">
+        <f:if condition="{typo3Version} >= 12">
+            <f:then>
+                <code>config/system/additional.php</code>
+            </f:then>
+            <f:else>
+                <f:comment><!-- @todo Remove once support for TYPO3 v11 is dropped --></f:comment>
+                <code>typo3conf/AdditionalConfiguration.php</code>
+            </f:else>
+        </f:if>
+    </div>
+</div>
+
+
+</html>

Resources/Private/Templates/List.html

@@ -8,10 +8,10 @@ <h1>{f:translate(key: 'header.list', extensionName: 'Mailqueue')}</h1>
 
     <f:if condition="{unsupportedTransport}">
         <f:then>
-            <f:be.infobox state="2"
-                          title="{f:translate(key: 'alert.unsupportedTransport.title', extensionName: 'Mailqueue')}"
-                          message="{f:translate(key: 'alert.unsupportedTransport.message', arguments: '{0: unsupportedTransport}', extensionName: 'Mailqueue')}"
-            />
+            <f:render partial="List/UnsupportedTransport" arguments="{
+                transport: unsupportedTransport,
+                typo3Version: typo3Version
+            }" />
         </f:then>
         <f:else>
             <f:render partial="List/Queue" arguments="{