Add Locale extender for language pack extensions

src/Extend/Locale.php

@@ -0,0 +1,75 @@
+<?php
+
+/*
+ * This file is part of Flarum.
+ *
+ * (c) Toby Zerner <toby.zerner@gmail.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Flarum\Extend;
+
+use DirectoryIterator;
+use Flarum\Locale\LocaleManager;
+use Illuminate\Contracts\Container\Container;
+use RuntimeException;
+
+class Locale implements Extender
+{
+    protected $directory;
+
+    public function __construct($directory)
+    {
+        $this->directory = $directory;
+    }
+
+    public function apply(Container $container)
+    {
+        $this->loadLanguagePackFrom(
+            $this->directory,
+            $container->make(LocaleManager::class)
+        );
+    }
+
+    private function loadLanguagePackFrom($directory, LocaleManager $locales)
+    {
+        $name = $title = basename($directory);
+
+        if (file_exists($manifest = $directory.'/composer.json')) {
+            $json = json_decode(file_get_contents($manifest), true);
+
+            if (empty($json)) {
+                throw new RuntimeException("Error parsing composer.json in $name: ".json_last_error_msg());
+            }
+
+            $locale = array_get($json, 'extra.flarum-locale.code');
+            $title = array_get($json, 'extra.flarum-locale.title', $title);
+        }
+
+        if (! isset($locale)) {
+            throw new RuntimeException("Language pack $name must define \"extra.flarum-locale.code\" in composer.json.");
+        }
+
+        $locales->addLocale($locale, $title);
+
+        if (! is_dir($localeDir = $directory.'/locale')) {
+            throw new RuntimeException("Language pack $name must have a \"locale\" subdirectory.");
+        }
+
+        if (file_exists($file = $localeDir.'/config.js')) {
+            $locales->addJsFile($locale, $file);
+        }
+
+        if (file_exists($file = $localeDir.'/config.css')) {
+            $locales->addCssFile($locale, $file);
+        }
+
+        foreach (new DirectoryIterator($localeDir) as $file) {
+            if ($file->isFile() && in_array($file->getExtension(), ['yml', 'yaml'])) {
+                $locales->addTranslations($locale, $file->getPathname());
+            }
+        }
+    }
+}