MAGETWO-38844: Contribution of Ogres Sprint 31

Merge remote-tracking branch 'ogresCE/MAGETWO-30245-uninstall-modules-via-cli-PR' into PR_Branch

Author: mazhalai

app/code/Magento/Theme/Console/Command/ThemeUninstallCommand.php

@@ -0,0 +1,92 @@
+<?php
+/**
+ * Copyright © 2015 Magento. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+namespace Magento\Theme\Model;
+
+use Magento\Store\Model\StoreManagerInterface;
+use Magento\Framework\View\DesignInterface;
+use Magento\Framework\View\Design\Theme\ThemeProviderInterface;
+use Magento\Framework\App\Config\ValueInterface;
+use Magento\Store\Model\ScopeInterface;
+
+/**
+ * Class ThemeValidator
+ */
+class ThemeValidator
+{
+
+    /**
+     * Store Manager
+     *
+     * @var StoreManagerInterface $storeManager
+     */
+    private $storeManager;
+
+    /**
+     * Provider for themes registered in db
+     *
+     * @var ThemeProviderInterface $themeProvider
+     */
+    private $themeProvider;
+
+    /**
+     * Configuration Data
+     *
+     * @var ValueInterface $configData
+     */
+    private $configData;
+
+
+    /**
+     * @param StoreManagerInterface $storeManager
+     * @param ThemeProviderInterface $themeProvider
+     * @param ValueInterface $configData
+     */
+    public function __construct(
+        StoreManagerInterface $storeManager,
+        ThemeProviderInterface $themeProvider,
+        ValueInterface $configData
+    ) {
+        $this->storeManager = $storeManager;
+        $this->themeProvider = $themeProvider;
+        $this->configData = $configData;
+    }
+
+    /**
+     * Validate the theme if being in use in default, website, or store.
+     *
+     * @param string[] $themePaths
+     * @return array
+     */
+    public function validateIsThemeInUse($themePaths)
+    {
+        $messages = [];
+        $themesById = [];
+        foreach ($themePaths as $themePath) {
+            $theme = $this->themeProvider->getThemeByFullPath($themePath);
+            $themesById[$theme->getId()] = $themePath;
+        }
+        $configData = $this->configData
+            ->getCollection()
+            ->addFieldToFilter('path', DesignInterface::XML_PATH_THEME_ID)
+            ->addFieldToFilter('value', ['in' => array_keys($themesById)]);
+        foreach ($configData as $row) {
+            switch($row['scope']) {
+                case 'default':
+                    $messages[] = $themesById[$row['value']] . ' is in use in default config';
+                    break;
+                case ScopeInterface::SCOPE_WEBSITES:
+                    $messages[] = $themesById[$row['value']] . ' is in use in website '
+                        . $this->storeManager->getWebsite($row['scope_id'])->getName();
+                    break;
+                case ScopeInterface::SCOPE_STORES:
+                    $messages[] = $themesById[$row['value']] . ' is in use in store '
+                        . $this->storeManager->getStore($row['scope_id'])->getName();
+                    break;
+            }
+        }
+        return $messages;
+    }
+}