implement copying of Stations for Seminary copy feature

www/analytics/core/AssetManager/UIAsset.php

@@ -0,0 +1,61 @@
+<?php
+/**
+ * Piwik - Open source web analytics
+ *
+ * @link http://piwik.org
+ * @license http://www.gnu.org/licenses/gpl-3.0.html GPL v3 or later
+ *
+ */
+namespace Piwik\AssetManager;
+
+use Exception;
+
+abstract class UIAsset
+{
+    abstract public function validateFile();
+
+    /**
+     * @return string
+     */
+    abstract public function getAbsoluteLocation();
+
+    /**
+     * @return string
+     */
+    abstract public function getRelativeLocation();
+
+    /**
+     * @return string
+     */
+    abstract public function getBaseDirectory();
+
+    /**
+     * Removes the previous file if it exists.
+     * Also tries to remove compressed version of the file.
+     *
+     * @see ProxyStaticFile::serveStaticFile(serveFile
+     * @throws Exception if the file couldn't be deleted
+     */
+    abstract public function delete();
+
+    /**
+     * @param string $content
+     * @throws \Exception
+     */
+    abstract public function writeContent($content);
+
+    /**
+     * @return string
+     */
+    abstract public function getContent();
+
+    /**
+     * @return boolean
+     */
+    abstract public function exists();
+
+    /**
+     * @return int
+     */
+    abstract public function getModificationDate();
+}