Refactor the web app bootstrapping code

- All custom JS variables are now preloaded into the `app.data` object, rather than directly on the `app` object. This means that admin settings are available in `app.data.settings` rather than `app.settings`, etc.
- Cleaner route handler generation
- Renamed ConfigureClientView to ConfigureWebApp, though the former still exists and is deprecated
- Partial fix for #881 (strips ?nojs=1 from URL if possible, so that refreshing will attempt to load JS version again)

src/Http/WebApp/AbstractWebApp.php

@@ -0,0 +1,188 @@
+<?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\Http\WebApp;
+
+use Flarum\Http\Controller;
+use Flarum\Locale\LocaleManager;
+use Flarum\Settings\SettingsRepositoryInterface;
+
+abstract class AbstractWebApp
+{
+    /**
+     * @var WebAppAssetsFactory
+     */
+    protected $assets;
+
+    /**
+     * @var WebAppViewFactory
+     */
+    protected $view;
+
+    /**
+     * @var SettingsRepositoryInterface
+     */
+    protected $settings;
+
+    /**
+     * @var LocaleManager
+     */
+    protected $locales;
+
+    /**
+     * @param WebAppAssetsFactory $assets
+     * @param WebAppViewFactory $view
+     * @param SettingsRepositoryInterface $settings
+     * @param LocaleManager $locales
+     */
+    public function __construct(WebAppAssetsFactory $assets, WebAppViewFactory $view, SettingsRepositoryInterface $settings, LocaleManager $locales)
+    {
+        $this->assets = $assets;
+        $this->view = $view;
+        $this->settings = $settings;
+        $this->locales = $locales;
+    }
+
+    /**
+     * @return WebAppView
+     */
+    public function getView()
+    {
+        $view = $this->view->make($this->getLayout(), $this->getAssets());
+
+        $this->addDefaultAssets($view);
+        $this->addCustomLess($view);
+        $this->addTranslations($view);
+
+        return $view;
+    }
+
+    /**
+     * @return WebAppAssets
+     */
+    public function getAssets()
+    {
+        return $this->assets->make($this->getName());
+    }
+
+    /**
+     * Get the name of the client.
+     *
+     * @return string
+     */
+    abstract protected function getName();
+
+    /**
+     * Get the path to the client layout view.
+     *
+     * @return string
+     */
+    protected function getLayout()
+    {
+        return __DIR__.'/../../../views/'.$this->getName().'.blade.php';
+    }
+
+    /**
+     * Get a regular expression to match against translation keys.
+     *
+     * @return string
+     */
+    protected function getTranslationFilter()
+    {
+        return '/^[^\.]+\.(?:'.$this->getName().'|lib)\./';
+    }
+
+    /**
+     * @param WebAppView $view
+     */
+    private function addDefaultAssets(WebAppView $view)
+    {
+        $root = __DIR__.'/../../..';
+        $name = $this->getName();
+
+        $view->getJs()->addFile("$root/js/$name/dist/app.js");
+        $view->getCss()->addFile("$root/less/$name/app.less");
+    }
+
+    /**
+     * @param WebAppView $view
+     */
+    private function addCustomLess(WebAppView $view)
+    {
+        $css = $view->getCss();
+        $localeCss = $view->getLocaleCss();
+
+        $lessVariables = function () {
+            $less = '';
+
+            foreach ($this->getLessVariables() as $name => $value) {
+                $less .= "@$name: $value;";
+            }
+
+            return $less;
+        };
+
+        $css->addString($lessVariables);
+        $localeCss->addString($lessVariables);
+
+        $css->addString(function () {
+            return $this->settings->get('custom_less');
+        });
+    }
+
+    /**
+     * Get the values of any LESS variables to compile into the CSS, based on
+     * the forum's configuration.
+     *
+     * @return array
+     */
+    private function getLessVariables()
+    {
+        return [
+            'config-primary-color'   => $this->settings->get('theme_primary_color') ?: '#000',
+            'config-secondary-color' => $this->settings->get('theme_secondary_color') ?: '#000',
+            'config-dark-mode'       => $this->settings->get('theme_dark_mode') ? 'true' : 'false',
+            'config-colored-header'  => $this->settings->get('theme_colored_header') ? 'true' : 'false'
+        ];
+    }
+
+    /**
+     * @param WebAppView $view
+     */
+    private function addTranslations(WebAppView $view)
+    {
+        $translations = array_get($this->locales->getTranslator()->getMessages(), 'messages', []);
+
+        $translations = $this->filterTranslations($translations);
+
+        $view->getLocaleJs()->setTranslations($translations);
+    }
+
+    /**
+     * Take a selection of keys from a collection of translations.
+     *
+     * @param array $translations
+     * @return array
+     */
+    private function filterTranslations(array $translations)
+    {
+        $filter = $this->getTranslationFilter();
+
+        if (! $filter) {
+            return [];
+        }
+
+        $filtered = array_filter(array_keys($translations), function ($id) use ($filter) {
+            return preg_match($filter, $id);
+        });
+
+        return array_only($translations, $filtered);
+    }
+}