EZP-29932: As a Developer I want list of Languages based on User's br…

…owser settings (ezsystems#2507)

* EZP-29932: As a Developer I want list of Languages based on User's browser settings

* EZP-29932: proper kernel docblocks

* EZP-29925: Extract UserLanguagePreferenceProviderInterface

* EZP-29932: Add fallback for getName and getDescription when mainLanguageCode is not provided

eZ/Bundle/EzPublishCoreBundle/Resources/config/locale.yml

@@ -44,6 +44,47 @@ parameters:
         tur-TR: tr_TR
         ukr-UA: uk_UA
 
+    ezpublish.locale.browser_map:
+        au: ['eng-AU']
+        be: ['fre-BE']
+        br: ['por-BR']
+        ca: ['eng-CA']
+        cn: ['chi-CN']
+        cz: ['cze-CZ']
+        de: ['ger-DE']
+        dk: ['dan-DK']
+        en: ['eng-GB', 'eng-US']
+        en-us: ['eng-US']
+        es: ['esl-ES']
+        fi: ['fin-FI']
+        fr: ['fre-FR']
+        gb: ['eng-GB']
+        gr: ['ell-GR']
+        hk: ['chi-HK']
+        hr: ['cro-HR']
+        hu: ['hun-HU']
+        id: ['ind-ID']
+        il: ['heb-IL']
+        in: ['hin-IN']
+        it: ['ita-IT']
+        jp: ['jpn-JP']
+        kr: ['kor-KR']
+        mx: ['esl-MX']
+        mz: ['por-MZ']
+        nl: ['dut-NL']
+        no: ['nor-NO']
+        nz: ['eng-NZ']
+        pl: ['pol-PL']
+        pt: ['por-PT']
+        rs: ['srp-RS']
+        ru: ['rus-RU']
+        sa: ['ara-SA']
+        se: ['swe-SE']
+        sk: ['slk-SK']
+        tr: ['tur-TR']
+        tw: ['chi-TW']
+        ua: ['ukr-UA']
+
     ezpublish.locale.converter.class: eZ\Publish\Core\MVC\Symfony\Locale\LocaleConverter
 
 services:
@@ -57,3 +98,8 @@ services:
         arguments: ["@request_stack", "%kernel.default_locale%", "@?router"]
         tags:
             - { name: kernel.event_subscriber }
+
+    eZ\Publish\Core\MVC\Symfony\Locale\UserLanguagePreferenceProvider:
+        autowire: true
+        arguments:
+            $languageCodesMap: '%ezpublish.locale.browser_map%'

eZ/Publish/Core/MVC/Symfony/Locale/Tests/UserLanguagePreferenceProviderTest.php

@@ -0,0 +1,89 @@
+<?php
+
+/**
+ * @copyright Copyright (C) eZ Systems AS. All rights reserved.
+ * @license For full copyright and license information view LICENSE file distributed with this source code.
+ */
+declare(strict_types=1);
+
+namespace eZ\Publish\Core\MVC\Symfony\Locale\Tests;
+
+use eZ\Publish\Core\MVC\Symfony\Locale\UserLanguagePreferenceProvider;
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\HttpFoundation\HeaderBag;
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\RequestStack;
+use Symfony\Component\Yaml\Yaml;
+
+class UserLanguagePreferenceProviderTest extends TestCase
+{
+    /**
+     * @var \eZ\Publish\Core\MVC\Symfony\Locale\UserLanguagePreferenceProviderInterface
+     */
+    private $userLanguagePreferenceProvider;
+
+    /**
+     * @var \PHPUnit\Framework\MockObject\MockObject|\Symfony\Component\HttpFoundation\RequestStack
+     */
+    private $requestStackMock;
+
+    public function setUp()
+    {
+        $this->requestStackMock = $this->createMock(RequestStack::class);
+
+        $this->userLanguagePreferenceProvider = new UserLanguagePreferenceProvider(
+            $this->requestStackMock,
+            $this->getLanguageCodesMap()
+        );
+    }
+
+    /**
+     * @dataProvider providerForTestGetPreferredLanguages
+     *
+     * @param array $userLanguages
+     * @param array $expectedEzLanguageCodes
+     */
+    public function testGetPreferredLanguages(array $userLanguages, array $expectedEzLanguageCodes)
+    {
+        $request = new Request();
+        $request->headers = new HeaderBag(
+            [
+                'Accept-Language' => implode(', ', $userLanguages),
+            ]
+        );
+        $this
+            ->requestStackMock
+            ->expects($this->once())
+            ->method('getCurrentRequest')
+            ->willReturn($request);
+
+        self::assertEquals(
+            $expectedEzLanguageCodes,
+            $this->userLanguagePreferenceProvider->getPreferredLanguages()
+        );
+    }
+
+    /**
+     * @see testGetPreferredLanguages
+     *
+     * @return array
+     */
+    public function providerForTestGetPreferredLanguages(): array
+    {
+        return [
+            [['pl'], ['pol-PL']],
+            [['pol-PL'], ['pol-PL']],
+            [['fr'], ['fre-FR']],
+            [['en'], ['eng-GB', 'eng-US']],
+        ];
+    }
+
+    private function getLanguageCodesMap(): array
+    {
+        $config = Yaml::parseFile(
+            realpath(dirname(__DIR__, 6) . '/Bundle/EzPublishCoreBundle/Resources/config/locale.yml')
+        );
+
+        return $config['parameters']['ezpublish.locale.browser_map'];
+    }
+}

eZ/Publish/Core/MVC/Symfony/Locale/UserLanguagePreferenceProvider.php

@@ -0,0 +1,70 @@
+<?php
+
+/**
+ * @copyright Copyright (C) eZ Systems AS. All rights reserved.
+ * @license For full copyright and license information view LICENSE file distributed with this source code.
+ */
+declare(strict_types=1);
+
+namespace eZ\Publish\Core\MVC\Symfony\Locale;
+
+use Symfony\Component\HttpFoundation\Request;
+use Symfony\Component\HttpFoundation\RequestStack;
+
+class UserLanguagePreferenceProvider implements UserLanguagePreferenceProviderInterface
+{
+    /**
+     * @var \Symfony\Component\HttpFoundation\RequestStack
+     */
+    private $requestStack;
+
+    /**
+     * @var array
+     */
+    private $languageCodesMap;
+
+    /**
+     * @param \Symfony\Component\HttpFoundation\RequestStack $requestStack
+     * @param array $languageCodesMap
+     */
+    public function __construct(RequestStack $requestStack, array $languageCodesMap)
+    {
+        $this->requestStack = $requestStack;
+        $this->languageCodesMap = $languageCodesMap;
+    }
+
+    public function getPreferredLocales(Request $request = null): array
+    {
+        $request = $request ?? $this->requestStack->getCurrentRequest();
+        $preferredLocales = $request->headers->get('Accept-Language') ?? '';
+        $preferredLocales = array_reduce(
+            explode(',', $preferredLocales),
+            function (array $result, string $languageWithQuality) {
+                [$language, $quality] = array_merge(explode(';q=', $languageWithQuality), [1]);
+                $result[$language] = (float) $quality;
+
+                return $result;
+            },
+            []
+        );
+        arsort($preferredLocales);
+
+        return array_keys($preferredLocales);
+    }
+
+    public function getPreferredLanguages(): array
+    {
+        $languageCodes = [];
+        foreach ($this->getPreferredLocales() as $locale) {
+            $locale = strtolower($locale);
+            if (isset($this->languageCodesMap[$locale])) {
+                $languageCodes = array_merge($languageCodes, $this->languageCodesMap[$locale]);
+            } elseif (preg_match('/^([a-z]{3})-([a-z]{2})$/', $locale, $matches)) {
+                // if the given locale is already in the eZ format
+                $languageCodes[] = strtolower($matches[1]) . '-' . strtoupper($matches[2]);
+            }
+        }
+
+        return array_unique($languageCodes);
+    }
+}

eZ/Publish/Core/MVC/Symfony/Locale/UserLanguagePreferenceProviderInterface.php

@@ -0,0 +1,33 @@
+<?php
+
+/**
+ * @copyright Copyright (C) eZ Systems AS. All rights reserved.
+ * @license For full copyright and license information view LICENSE file distributed with this source code.
+ */
+declare(strict_types=1);
+
+namespace eZ\Publish\Core\MVC\Symfony\Locale;
+
+use Symfony\Component\HttpFoundation\Request;
+
+/**
+ * Provides list of user-preferred languages.
+ */
+interface UserLanguagePreferenceProviderInterface
+{
+    /**
+     * Return a list of user's browser preferred locales directly from Accept-Language header.
+     *
+     * @param \Symfony\Component\HttpFoundation\Request request to retrieve information from, use current if null
+     *
+     * @return string[]
+     */
+    public function getPreferredLocales(Request $request = null): array;
+
+    /**
+     * List of eZ Language codes.
+     *
+     * @return string[]
+     */
+    public function getPreferredLanguages(): array;
+}

eZ/Publish/Core/Repository/Values/MultiLanguageDescriptionTrait.php

@@ -43,6 +43,8 @@ public function getDescription($languageCode = null)
             }
         }
 
-        return $this->descriptions[$this->mainLanguageCode];
+        return isset($this->descriptions[$this->mainLanguageCode])
+            ? $this->descriptions[$this->mainLanguageCode]
+            : reset($this->descriptions);
     }
 }

eZ/Publish/Core/Repository/Values/MultiLanguageNameTrait.php

@@ -43,6 +43,8 @@ public function getName($languageCode = null)
             }
         }
 
-        return $this->names[$this->mainLanguageCode];
+        return isset($this->names[$this->mainLanguageCode])
+            ? $this->names[$this->mainLanguageCode]
+            : reset($this->names);
     }
 }