Expose Sheet::isActive() to provide info about the last active sheet (#405)

src/Spout/Reader/ODS/Helper/SettingsHelper.php

@@ -0,0 +1,51 @@
+<?php
+
+namespace Box\Spout\Reader\ODS\Helper;
+
+use Box\Spout\Reader\Exception\XMLProcessingException;
+use Box\Spout\Reader\Wrapper\XMLReader;
+
+/**
+ * Class SettingsHelper
+ * This class provides helper functions to extract data from the "settings.xml" file.
+ *
+ * @package Box\Spout\Reader\ODS\Helper
+ */
+class SettingsHelper
+{
+    const SETTINGS_XML_FILE_PATH = 'settings.xml';
+
+    /** Definition of XML nodes name and attribute used to parse settings data */
+    const XML_NODE_CONFIG_ITEM = 'config:config-item';
+    const XML_ATTRIBUTE_CONFIG_NAME = 'config:name';
+    const XML_ATTRIBUTE_VALUE_ACTIVE_TABLE = 'ActiveTable';
+
+    /**
+     * @param string $filePath Path of the file to be read
+     * @return string|null Name of the sheet that was defined as active or NULL if none found
+     */
+    public function getActiveSheetName($filePath)
+    {
+        $xmlReader = new XMLReader();
+        if ($xmlReader->openFileInZip($filePath, self::SETTINGS_XML_FILE_PATH) === false) {
+            return null;
+        }
+
+        $activeSheetName = null;
+
+        try {
+            while ($xmlReader->readUntilNodeFound(self::XML_NODE_CONFIG_ITEM)) {
+                if ($xmlReader->getAttribute(self::XML_ATTRIBUTE_CONFIG_NAME) === self::XML_ATTRIBUTE_VALUE_ACTIVE_TABLE) {
+                    $activeSheetName = $xmlReader->readString();
+                    break;
+                }
+            }
+        } catch (XMLProcessingException $exception) {
+            // do nothing
+        }
+
+        $xmlReader->close();
+
+        return $activeSheetName;
+    }
+}