From 470b4ab5382d5d84198e5299c040cc62e29595ef Mon Sep 17 00:00:00 2001
From: Marc Jauvin <marc.jauvin@gmail.com>
Date: Sat, 17 Oct 2020 08:43:17 -0400
Subject: [PATCH] mail templates/views can now be localized (#605)

Add mail templates localization.

Co-authored-by: Luke Towers <github@luketowers.ca>
Co-authored-by: Ben Thomson <git@alfreido.com>
---
 Plugin.php                |  7 ++++
 README.md                 | 10 ++---
 classes/EventRegistry.php | 79 ++++++++++++++++++++++++++++++++++++++-
 3 files changed, 89 insertions(+), 7 deletions(-)

diff --git a/Plugin.php b/Plugin.php
index f0a684c5..0e07072c 100644
--- a/Plugin.php
+++ b/Plugin.php
@@ -37,6 +37,13 @@ public function pluginDetails()
 
     public function register()
     {
+        /* 
+         * Load localized version of mail templates (akin to localized CMS content files)
+         */
+        Event::listen('mailer.beforeAddContent', function ($mailer, $message, $view, $data, $raw, $plain) {
+            return EventRegistry::instance()->findLocalizedMailViewContent($mailer, $message, $view, $data, $raw, $plain);
+        }, 1);
+
         /*
          * Defer event with low priority to let others contribute before this registers.
          */
diff --git a/README.md b/README.md
index 00a83cb8..7b34775f 100644
--- a/README.md
+++ b/README.md
@@ -113,13 +113,13 @@ Add the `--purge` option to clear old messages first:
     
     php artisan translate:scan --purge
     
-## Content translation
+## Content & mail template translation
 
-This plugin activates a feature in the CMS that allows content files to use language suffixes, for example:
+This plugin activates a feature in the CMS that allows content & mail template files to use language suffixes, for example:
 
-* **welcome.htm** will contain the content in the default language.
-* **welcome.ru.htm** will contain the content in Russian.
-* **welcome.fr.htm** will contain the content in French.
+* **welcome.htm** will contain the content or mail template in the default language.
+* **welcome.ru.htm** will contain the content or mail template in Russian.
+* **welcome.fr.htm** will contain the content or mail template in French.
 
 ## Model translation
 
diff --git a/classes/EventRegistry.php b/classes/EventRegistry.php
index 6459d0c1..76faed92 100644
--- a/classes/EventRegistry.php
+++ b/classes/EventRegistry.php
@@ -1,15 +1,17 @@
 <?php namespace RainLab\Translate\Classes;
 
-use Str;
+use App;
+use Exception;
 use File;
+use Str;
 use Cms\Classes\Page;
 use Cms\Classes\Content;
+use System\Classes\MailManager;
 use System\Classes\PluginManager;
 use RainLab\Translate\Models\Message;
 use RainLab\Translate\Models\Locale as LocaleModel;
 use RainLab\Translate\Classes\Translator;
 use RainLab\Translate\Classes\ThemeScanner;
-use Exception;
 
 /**
  * Registrant class for bootstrapping events
@@ -257,4 +259,77 @@ public function pruneTranslatedContentTemplates($templates)
             return !Str::endsWith($template->getBaseFileName(), $extensions);
         });
     }
+
+    /**
+     * Adds language suffixes to mail view files.
+     * @param  \October\Rain\Mail\Mailer $mailer
+     * @param  \Illuminate\Mail\Message $message
+     * @param  string $view
+     * @param  array $data
+     * @param  string $raw
+     * @param  string $plain
+     * @return bool|void Will return false if the translation process successfully replaced the original message with a translated version to prevent the original version from being processed.
+     */
+    public function findLocalizedMailViewContent($mailer, $message, $view, $data, $raw, $plain)
+    {
+        // Raw content cannot be localized at this level
+        if (!empty($raw)) {
+            return;
+        }
+
+        // Get the locale to use for this template
+        $locale = !empty($data['_current_locale']) ? $data['_current_locale'] : App::getLocale();
+
+        $factory = $mailer->getViewFactory();
+
+        if (!empty($view)) {
+            $view = $this->getLocalizedView($factory, $view, $locale);
+        }
+
+        if (!empty($plain)) {
+            $plain = $this->getLocalizedView($factory, $plain, $locale);
+        }
+
+        $code = $view ?: $plain;
+        if (empty($code)) {
+            return null;
+        }
+
+        $plainOnly = empty($view);
+
+        if (MailManager::instance()->addContentToMailer($message, $code, $data, $plainOnly)) {
+            // the caller who fired the event is expecting a FALSE response to halt the event
+            return false;
+        }
+    }
+
+
+    /**
+     * Search mail view files based on locale
+     * @param  \October\Rain\Mail\Mailer $mailer
+     * @param  \Illuminate\Mail\Message $message
+     * @param  string $code
+     * @param  string $locale
+     * @return string|null
+     */
+    public function getLocalizedView($factory, $code, $locale)
+    {
+        $locale = strtolower($locale);
+
+        $searchPaths[] = $locale;
+
+        if (str_contains($locale, '-')) {
+            list($lang) = explode('-', $locale);
+            $searchPaths[] = $lang;
+        }
+
+        foreach ($searchPaths as $path) {
+            $localizedView = sprintf('%s-%s', $code, $path);
+
+            if ($factory->exists($localizedView)) {
+                return $localizedView;
+            }
+        }
+        return null;
+    }
 }