various improvements

src/Spout/Reader/Common/Creator/InternalEntityFactoryInterface.php

@@ -2,9 +2,23 @@
 
 namespace Box\Spout\Reader\Common\Creator;
 
+use Box\Spout\Reader\Common\Entity\Cell;
+use Box\Spout\Reader\Common\Entity\Row;
+
 /**
  * Interface EntityFactoryInterface
  */
 interface InternalEntityFactoryInterface
 {
+    /**
+     * @param Cell[] $cells
+     * @return Row
+     */
+    public function createRow(array $cells = []);
+
+    /**
+     * @param mixed $cellValue
+     * @return Cell
+     */
+    public function createCell($cellValue);
 }

src/Spout/Reader/Common/Entity/Row.php

@@ -65,6 +65,14 @@ class Row
         return $this;
     }
 
+    /**
+     * @return int
+     */
+    public function getNumCells()
+    {
+        return count($this->cells);
+    }
+
     /**
      * @return array The row values, as array
      */

src/Spout/Reader/Common/Manager/RowManager.php

@@ -0,0 +1,65 @@
+<?php
+
+namespace Box\Spout\Reader\Common\Manager;
+
+use Box\Spout\Reader\Common\Creator\InternalEntityFactoryInterface;
+use Box\Spout\Reader\Common\Entity\Row;
+
+/**
+ * Class RowManager
+ */
+class RowManager
+{
+    /** @var InternalEntityFactoryInterface Factory to create entities */
+    private $entityFactory;
+
+    /**
+     * @param InternalEntityFactoryInterface $entityFactory Factory to create entities
+     */
+    public function __construct(InternalEntityFactoryInterface $entityFactory)
+    {
+        $this->entityFactory = $entityFactory;
+    }
+
+    /**
+     * Detect whether a row is considered empty.
+     * An empty row has all of its cells empty.
+     *
+     * @param Row $row
+     * @return bool
+     */
+    public function isEmpty(Row $row)
+    {
+        foreach ($row->getCells() as $cell) {
+            if (!$cell->isEmpty()) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    /**
+     * Fills the missing indexes of a row with empty cells.
+     *
+     * @param Row $row
+     * @return Row
+     */
+    public function fillMissingIndexesWithEmptyCells(Row $row)
+    {
+        if ($row->getNumCells() === 0) {
+            return $row;
+        }
+
+        $rowCells = $row->getCells();
+        $maxCellIndex = max(array_keys($rowCells));
+
+        for ($cellIndex = 0; $cellIndex < $maxCellIndex; $cellIndex++) {
+            if (!isset($rowCells[$cellIndex])) {
+                $row->setCellAtIndex($this->entityFactory->createCell(''), $cellIndex);
+            }
+        }
+
+        return $row;
+    }
+}