Detect user locale

classes/LocaleMiddleware.php

@@ -0,0 +1,61 @@
+<?php
+/**
+ * LocaleMiddleware class.
+ */
+namespace Alltube;
+
+use Slim\Http\Request;
+use Slim\Http\Response;
+use Teto\HTTP\AcceptLanguage;
+
+/**
+ * Detect user locale.
+ */
+class LocaleMiddleware
+{
+    /**
+     * Supported locales.
+     *
+     * @var array
+     */
+    private $locales = ['fr_FR', 'zh_CN'];
+
+    /**
+     * Test if a locale can be used for the current user.
+     *
+     * @param array $proposedLocale Locale array created by AcceptLanguage::parse()
+     *
+     * @return string Locale name if chosen, nothing otherwise
+     */
+    public function testLocale(array $proposedLocale)
+    {
+        foreach ($this->locales as $locale) {
+            $parsedLocale = AcceptLanguage::parse($locale);
+            if (isset($proposedLocale['language'])
+                && $parsedLocale[1]['language'] == $proposedLocale['language']
+                && $parsedLocale[1]['region'] == $proposedLocale['region']
+            ) {
+                return $proposedLocale['language'].'_'.$proposedLocale['region'];
+            }
+        }
+    }
+
+    /**
+     * Main middleware function
+     *
+     * @param Request  $request  PSR request
+     * @param Response $response PSR response
+     * @param callable $next     Next middleware
+     *
+     * @return Response
+     */
+    public function __invoke(Request $request, Response $response, callable $next)
+    {
+        $headers = $request->getHeader('Accept-Language');
+        $locale = AcceptLanguage::detect([$this, 'testLocale'], 'en_US', $headers[0]);
+        putenv('LANG='.$locale);
+        setlocale(LC_ALL, [$locale, $locale.'.utf8']);
+
+        return $next($request, $response);
+    }
+}