<?php
/**
 * Created by PhpStorm.
 * User: phperstar
 * Date: 2020/8/10
 * Time: 5:17 PM
 */
namespace Util\PHPExcel;

use Util\PHPExcel\Cell;
use Util\PHPExcel\CachedObjectStorageFactory;
use Util\PHPExcel\Shared\PHPExcelString;
use Util\PHPExcel\Worksheet\SheetView;
use Util\PHPExcel\Worksheet\PageSetup;
use Util\PHPExcel\Worksheet\RowDimension;
use Util\PHPExcel\Worksheet\ColumnDimension;
use Util\PHPExcel\Cell\DataType;


class Worksheet
{
    /**
     * Cacheable collection of cells
     *
     * @var PHPExcel_CachedObjectStorage_xxx
     */
    private $cellCollection;

    /**
     * Worksheet title
     *
     * @var string
     */
    private $title;

    /**
     * Invalid characters in sheet title
     *
     * @var array
     */
    private static $invalidCharacters = array('*', ':', '/', '\\', '?', '[', ']');

    /**
     * Parent spreadsheet
     *
     * @var PHPExcel
     */
    private $parent;

    /**
     * Dirty flag
     *
     * @var boolean
     */
    private $dirty = true;

    /* Sheet state */
    const SHEETSTATE_VISIBLE    = 'visible';
    const SHEETSTATE_HIDDEN     = 'hidden';
    const SHEETSTATE_VERYHIDDEN = 'veryHidden';

    /**
     * Freeze pane
     *
     * @var string
     */
    private $freezePane = '';

    /**
     * CodeName
     *
     * @var string
     */
    private $codeName = null;

    /**
     * Default row dimension
     *
     * @var RowDimension
     */
    private $defaultRowDimension;

    /**
     * Page setup
     *
     * @var PageSetup
     */
    private $pageSetup;

    /**
     * Collection of column dimensions
     *
     * @var ColumnDimension[]
     */
    private $columnDimensions = array();

    /**
     * Show gridlines?
     *
     * @var boolean
     */
    private $showGridlines = true;

    /**
     * Print gridlines?
     *
     * @var boolean
     */
    private $printGridlines = false;

    /**
     * Collection of row dimensions
     *
     * @var RowDimension[]
     */
    private $rowDimensions = array();

    /**
     * Default column dimension
     *
     * @var ColumnDimension
     */
    private $defaultColumnDimension = null;

    /**
     * Cached highest column
     *
     * @var string
     */
    private $cachedHighestColumn = 'A';

    /**
     * Cached highest row
     *
     * @var int
     */
    private $cachedHighestRow = 1;


    /**
     * Create a new worksheet
     *
     * @param PHPExcel $pParent
     * @param string $pTitle
     */
    public function __construct(PHPExcel $pParent = null, $pTitle = 'Worksheet')
    {

        $this->cellCollection = CachedObjectStorageFactory::getInstance($this);


        // Set parent and title
        $this->parent = $pParent;
        $this->setTitle($pTitle, false);

        // setTitle can change $pTitle
        $this->setCodeName($this->getTitle());
        $this->setSheetState(Worksheet::SHEETSTATE_VISIBLE);

        // Set page setup
        $this->pageSetup              = new PageSetup();
        // Set sheet view
        $this->sheetView              = new SheetView();
        // Default row dimension
        $this->defaultRowDimension    = new RowDimension(null);


       /*
       // Set page margins
       $this->pageMargins            = new PHPExcel_Worksheet_PageMargins();
       // Set page header/footer
       $this->headerFooter           = new PHPExcel_Worksheet_HeaderFooter();
       // Drawing collection
       $this->drawingCollection      = new ArrayObject();
       // Chart collection
       $this->chartCollection        = new ArrayObject();
       // Protection
       $this->protection             = new PHPExcel_Worksheet_Protection(); */

       // Default column dimension
       $this->defaultColumnDimension = new ColumnDimension(null);
       //$this->autoFilter             = new PHPExcel_Worksheet_AutoFilter(null, $this);
    }

    /**
     * Get collection of cells
     *
     * @param boolean $pSorted Also sort the cell collection?
     * @return PHPExcel_Cell[]
     */
    public function getCellCollection($pSorted = true)
    {
        if ($pSorted) {
            // Re-order cell collection
            return $this->sortCellCollection();
        }
        if ($this->cellCollection !== null) {
            return $this->cellCollection->getCellList();
        }
        return array();
    }

    /**
     * Sort collection of cells
     *
     * @return PHPExcel_Worksheet
     */
    public function sortCellCollection()
    {
        if ($this->cellCollection !== null) {
            return $this->cellCollection->getSortedCellList();
        }
        return array();
    }

    /**
     * Get title
     *
     * @return string
     */
    public function getTitle()
    {
        return $this->title;
    }

    /**
     * Set title
     *
     * @param string $pValue String containing the dimension of this worksheet
     * @param string $updateFormulaCellReferences boolean Flag indicating whether cell references in formulae should
     *            be updated to reflect the new sheet name.
     *          This should be left as the default true, unless you are
     *          certain that no formula cells on any worksheet contain
     *          references to this worksheet
     * @return PHPExcel_Worksheet
     */
    public function setTitle($pValue = 'Worksheet', $updateFormulaCellReferences = true)
    {
        // Is this a 'rename' or not?
        if ($this->getTitle() == $pValue) {
            return $this;
        }

        // Syntax check
        self::checkSheetTitle($pValue);

        // Old title
        $oldTitle = $this->getTitle();

        if ($this->parent) {
            // Is there already such sheet name?
            if ($this->parent->sheetNameExists($pValue)) {
                // Use name, but append with lowest possible integer

                if (PHPExcelString::CountCharacters($pValue) > 29) {
                    $pValue = PHPExcelString::Substring($pValue, 0, 29);
                }
                $i = 1;
                while ($this->parent->sheetNameExists($pValue . ' ' . $i)) {
                    ++$i;
                    if ($i == 10) {
                        if (PHPExcelString::CountCharacters($pValue) > 28) {
                            $pValue = PHPExcelString::Substring($pValue, 0, 28);
                        }
                    } elseif ($i == 100) {
                        if (PHPExcelString::CountCharacters($pValue) > 27) {
                            $pValue = PHPExcelString::Substring($pValue, 0, 27);
                        }
                    }
                }

                $altTitle = $pValue . ' ' . $i;
                return $this->setTitle($altTitle, $updateFormulaCellReferences);
            }
        }

        // Set title
        $this->title = $pValue;
        $this->dirty = true;

        if ($this->parent && $this->parent->getCalculationEngine()) {
            // New title
            $newTitle = $this->getTitle();
            $this->parent->getCalculationEngine()
                ->renameCalculationCacheForWorksheet($oldTitle, $newTitle);
            if ($updateFormulaCellReferences) {
                PHPExcel_ReferenceHelper::getInstance()->updateNamedFormulas($this->parent, $oldTitle, $newTitle);
            }
        }

        return $this;
    }

    /**
     * Check sheet title for valid Excel syntax
     *
     * @param string $pValue The string to check
     * @return string The valid string
     * @throws
     */
    private static function checkSheetTitle($pValue)
    {
        // Some of the printable ASCII characters are invalid:  * : / \ ? [ ]
        if (str_replace(self::$invalidCharacters, '', $pValue) !== $pValue) {
            throw new \Exception('Invalid character found in sheet title');
        }

        // Maximum 31 characters allowed for sheet title
        if (PHPExcelString::CountCharacters($pValue) > 31) {
            throw new \Exception('Maximum 31 characters allowed in sheet title.');
        }

        return $pValue;
    }

    /**
     * Get array of invalid characters for sheet title
     *
     * @return array
     */
    public static function getInvalidCharacters()
    {
        return self::$invalidCharacters;
    }

    /**
     * Get parent
     *
     * @return PHPExcel
     */
    public function getParent()
    {
        return $this->parent;
    }

    /**
     * Re-bind parent
     *
     * @param PHPExcel $parent
     * @return Worksheet
     */
    public function rebindParent(PHPExcel $parent)
    {
        if ($this->parent !== null) {
            $namedRanges = $this->parent->getNamedRanges();
            foreach ($namedRanges as $namedRange) {
                $parent->addNamedRange($namedRange);
            }

            $this->parent->removeSheetByIndex(
                $this->parent->getIndex($this)
            );
        }
        $this->parent = $parent;

        return $this;
    }


    /**
     * Disconnect all cells from this PHPExcel_Worksheet object,
     *    typically so that the worksheet object can be unset
     *
     */
    public function disconnectCells()
    {
        if ($this->cellCollection !== null) {
            $this->cellCollection->unsetWorksheetCells();
            $this->cellCollection = null;
        }
        //    detach ourself from the workbook, so that it can then delete this worksheet successfully
        $this->parent = null;
    }

    /**
     * Get hash code
     *
     * @return string    Hash code
     */
    public function getHashCode()
    {
        if ($this->dirty) {
            $this->hash = md5($this->title . $this->autoFilter . ($this->protection->isProtectionEnabled() ? 't' : 'f') . __CLASS__);
            $this->dirty = false;
        }
        return $this->hash;
    }

    /**
     * Set sheet state
     *
     * @param string $value Sheet state (visible, hidden, veryHidden)
     * @return PHPExcel_Worksheet
     */
    public function setSheetState($value = Worksheet::SHEETSTATE_VISIBLE)
    {
        $this->sheetState = $value;
        return $this;
    }

    /**
     * Get sheet state
     *
     * @return string Sheet state (visible, hidden, veryHidden)
     */
    public function getSheetState()
    {
        return $this->sheetState;
    }

    /**
     * Get sheet view
     *
     * @return PHPExcel_Worksheet_SheetView
     */
    public function getSheetView()
    {
        return $this->sheetView;
    }

    /**
     * Set sheet view
     *
     * @param PHPExcel_Worksheet_SheetView    $pValue
     * @return PHPExcel_Worksheet
     */
    public function setSheetView(SheetView $pValue)
    {
        $this->sheetView = $pValue;
        return $this;
    }

    /**
     * Get Freeze Pane
     *
     * @return string
     */
    public function getFreezePane()
    {
        return $this->freezePane;
    }

    /**
     * Freeze Pane
     *
     * @param    string        $pCell        Cell (i.e. A2)
     *                                    Examples:
     *                                        A2 will freeze the rows above cell A2 (i.e row 1)
     *                                        B1 will freeze the columns to the left of cell B1 (i.e column A)
     *                                        B2 will freeze the rows above and to the left of cell A2
     *                                            (i.e row 1 and column A)
     * @throws
     * @return PHPExcel_Worksheet
     */
    public function freezePane($pCell = '')
    {
        // Uppercase coordinate
        $pCell = strtoupper($pCell);
        if (strpos($pCell, ':') === false && strpos($pCell, ',') === false) {
            $this->freezePane = $pCell;
        } else {
            throw new \Exception('Freeze pane can not be set on a range of cells.');
        }
        return $this;
    }

    /**
     * Freeze Pane by using numeric cell coordinates
     *
     * @param int $pColumn    Numeric column coordinate of the cell
     * @param int $pRow        Numeric row coordinate of the cell
     * @throws    PHPExcel_Exception
     * @return PHPExcel_Worksheet
     */
    public function freezePaneByColumnAndRow($pColumn = 0, $pRow = 1)
    {
        return $this->freezePane(Cell::stringFromColumnIndex($pColumn) . $pRow);
    }

    /**
     * Select a range of cells.
     *
     * @param    string        $pCoordinate    Cell range, examples: 'A1', 'B2:G5', 'A:C', '3:6'
     * @throws    PHPExcel_Exception
     * @return PHPExcel_Worksheet
     */
    public function setSelectedCells($pCoordinate = 'A1')
    {
        // Uppercase coordinate
        $pCoordinate = strtoupper($pCoordinate);

        // Convert 'A' to 'A:A'
        $pCoordinate = preg_replace('/^([A-Z]+)$/', '${1}:${1}', $pCoordinate);

        // Convert '1' to '1:1'
        $pCoordinate = preg_replace('/^([0-9]+)$/', '${1}:${1}', $pCoordinate);

        // Convert 'A:C' to 'A1:C1048576'
        $pCoordinate = preg_replace('/^([A-Z]+):([A-Z]+)$/', '${1}1:${2}1048576', $pCoordinate);

        // Convert '1:3' to 'A1:XFD3'
        $pCoordinate = preg_replace('/^([0-9]+):([0-9]+)$/', 'A${1}:XFD${2}', $pCoordinate);

        if (strpos($pCoordinate, ':') !== false || strpos($pCoordinate, ',') !== false) {
            list($first, ) = Cell::splitRange($pCoordinate);
            $this->activeCell = $first[0];
        } else {
            $this->activeCell = $pCoordinate;
        }
        $this->selectedCells = $pCoordinate;
        return $this;
    }

    /**
     * Get tab color
     *
     * @return PHPExcel_Style_Color
     */
    public function getTabColor()
    {
        if ($this->tabColor === null) {
            $this->tabColor = new PHPExcel_Style_Color();
        }
        return $this->tabColor;
    }

    /**
     * Reset tab color
     *
     * @return PHPExcel_Worksheet
     */
    public function resetTabColor()
    {
        $this->tabColor = null;
        unset($this->tabColor);

        return $this;
    }

    /**
     * Define the code name of the sheet
     *
     * @param null|string Same rule as Title minus space not allowed (but, like Excel, change silently space to underscore)
     * @return objWorksheet
     * @throws PHPExcel_Exception
     */
    public function setCodeName($pValue = null)
    {
        // Is this a 'rename' or not?
        if ($this->getCodeName() == $pValue) {
            return $this;
        }
        $pValue = str_replace(' ', '_', $pValue);//Excel does this automatically without flinching, we are doing the same
        // Syntax check
        // throw an exception if not valid
        self::checkSheetCodeName($pValue);

        // We use the same code that setTitle to find a valid codeName else not using a space (Excel don't like) but a '_'

        if ($this->getParent()) {
            // Is there already such sheet name?
            if ($this->getParent()->sheetCodeNameExists($pValue)) {
                // Use name, but append with lowest possible integer

                if (PHPExcelString::CountCharacters($pValue) > 29) {
                    $pValue = PHPExcelString::Substring($pValue, 0, 29);
                }

                $i = 1;
                while ($this->getParent()->sheetCodeNameExists($pValue . '_' . $i)) {
                    ++$i;
                    if ($i == 10) {
                        if (PHPExcelString::CountCharacters($pValue) > 28) {
                            $pValue = PHPExcelString::Substring($pValue, 0, 28);
                        }
                    } elseif ($i == 100) {
                        if (PHPExcelString::CountCharacters($pValue) > 27) {
                            $pValue = PHPExcelString::Substring($pValue, 0, 27);
                        }
                    }
                }

                $pValue = $pValue . '_' . $i;// ok, we have a valid name
                //codeName is'nt used in formula : no need to call for an update
                //return $this->setTitle($altTitle, $updateFormulaCellReferences);
            }
        }

        $this->codeName=$pValue;
        return $this;
    }

    /**
     * Return the code name of the sheet
     *
     * @return null|string
     */
    public function getCodeName()
    {
        return $this->codeName;
    }
    /**
     * Sheet has a code name ?
     * @return boolean
     */
    public function hasCodeName()
    {
        return !(is_null($this->codeName));
    }

    /**
     * Check sheet code name for valid Excel syntax
     *
     * @param string $pValue The string to check
     * @return string The valid string
     * @throws
     */
    private static function checkSheetCodeName($pValue)
    {
        $CharCount = PHPExcelString::CountCharacters($pValue);
        if ($CharCount == 0) {
            throw new \Exception('Sheet code name cannot be empty.');
        }
        // Some of the printable ASCII characters are invalid:  * : / \ ? [ ] and  first and last characters cannot be a "'"
        if ((str_replace(self::$invalidCharacters, '', $pValue) !== $pValue) ||
            (PHPExcelString::Substring($pValue, -1, 1)=='\'') ||
            (PHPExcelString::Substring($pValue, 0, 1)=='\'')) {
            throw new \Exception('Invalid character found in sheet code name');
        }

        // Maximum 31 characters allowed for sheet title
        if ($CharCount > 31) {
            throw new \Exception('Maximum 31 characters allowed in sheet code name.');
        }

        return $pValue;
    }

    /**
     * Show summary right? (Row/Column outlining)
     *
     * @return boolean
     */
    public function getShowSummaryRight()
    {
        return $this->showSummaryRight;
    }

    /**
     * Set show summary right
     *
     * @param boolean $pValue    Show summary right (true/false)
     * @return PHPExcel_Worksheet
     */
    public function setShowSummaryRight($pValue = true)
    {
        $this->showSummaryRight = $pValue;
        return $this;
    }

    /**
     * Show summary below? (Row/Column outlining)
     *
     * @return boolean
     */
    public function getShowSummaryBelow()
    {
        return $this->showSummaryBelow;
    }

    /**
     * Set show summary below
     *
     * @param boolean $pValue    Show summary below (true/false)
     * @return PHPExcel_Worksheet
     */
    public function setShowSummaryBelow($pValue = true)
    {
        $this->showSummaryBelow = $pValue;
        return $this;
    }

    /**
     * Get page setup
     *
     * @return PHPExcel_Worksheet_PageSetup
     */
    public function getPageSetup()
    {
        return $this->pageSetup;
    }

    /**
     * Set page setup
     *
     * @param PHPExcel_Worksheet_PageSetup    $pValue
     * @return PHPExcel_Worksheet
     */
    public function setPageSetup(PageSetup $pValue)
    {
        $this->pageSetup = $pValue;
        return $this;
    }

    /**
     * Get default row dimension
     *
     * @return PHPExcel_Worksheet_RowDimension
     */
    public function getDefaultRowDimension()
    {
        return $this->defaultRowDimension;
    }

    /**
     * Get collection of column dimensions
     *
     * @return PHPExcel_Worksheet_ColumnDimension[]
     */
    public function getColumnDimensions()
    {
        return $this->columnDimensions;
    }

    /**
     * Get column dimension at a specific column
     *
     * @param string $pColumn String index of the column
     * @return PHPExcel_Worksheet_ColumnDimension
     */
    public function getColumnDimension($pColumn = 'A', $create = true)
    {
        // Uppercase coordinate
        $pColumn = strtoupper($pColumn);

        // Fetch dimensions
        if (!isset($this->columnDimensions[$pColumn])) {
            if (!$create) {
                return null;
            }
            $this->columnDimensions[$pColumn] = new ColumnDimension($pColumn);

            if (Cell::columnIndexFromString($this->cachedHighestColumn) < Cell::columnIndexFromString($pColumn)) {
                $this->cachedHighestColumn = $pColumn;
            }
        }
        return $this->columnDimensions[$pColumn];
    }

    /**
     * Show gridlines?
     *
     * @return boolean
     */
    public function getShowGridlines()
    {
        return $this->showGridlines;
    }

    /**
     * Set show gridlines
     *
     * @param boolean $pValue    Show gridlines (true/false)
     * @return PHPExcel_Worksheet
     */
    public function setShowGridlines($pValue = false)
    {
        $this->showGridlines = $pValue;
        return $this;
    }

    /**
     * Print gridlines?
     *
     * @return boolean
     */
    public function getPrintGridlines()
    {
        return $this->printGridlines;
    }

    /**
     * Set print gridlines
     *
     * @param boolean $pValue Print gridlines (true/false)
     * @return PHPExcel_Worksheet
     */
    public function setPrintGridlines($pValue = false)
    {
        $this->printGridlines = $pValue;
        return $this;
    }

    /**
     * Get row dimension at a specific row
     *
     * @param int $pRow Numeric index of the row
     * @return PHPExcel_Worksheet_RowDimension
     */
    public function getRowDimension($pRow = 1, $create = true)
    {
        // Found
        $found = null;

        // Get row dimension
        if (!isset($this->rowDimensions[$pRow])) {
            if (!$create) {
                return null;
            }
            $this->rowDimensions[$pRow] = new RowDimension($pRow);

            $this->cachedHighestRow = max($this->cachedHighestRow, $pRow);
        }
        return $this->rowDimensions[$pRow];
    }

    /**
     * Get default column dimension
     *
     * @return PHPExcel_Worksheet_ColumnDimension
     */
    public function getDefaultColumnDimension()
    {
        return $this->defaultColumnDimension;
    }

    /**
     * Get cell at a specific coordinate
     *
     * @param string $pCoordinate    Coordinate of the cell
     * @param boolean $createIfNotExists  Flag indicating whether a new cell should be created if it doesn't
     *                                       already exist, or a null should be returned instead
     * @throws
     * @return null|PHPExcel_Cell Cell that was found/created or null
     */
    public function getCell($pCoordinate = 'A1', $createIfNotExists = true)
    {
        // Check cell collection
        if ($this->cellCollection->isDataSet(strtoupper($pCoordinate))) {
            return $this->cellCollection->getCacheData($pCoordinate);
        }

        // Worksheet reference?
        if (strpos($pCoordinate, '!') !== false) {
            $worksheetReference = Worksheet::extractSheetTitle($pCoordinate, true);
            return $this->parent->getSheetByName($worksheetReference[0])->getCell(strtoupper($worksheetReference[1]), $createIfNotExists);
        }


        if ((!preg_match('/^'.Calculation::CALCULATION_REGEXP_CELLREF.'$/i', $pCoordinate, $matches)) &&
            (preg_match('/^'.Calculation::CALCULATION_REGEXP_NAMEDRANGE.'$/i', $pCoordinate, $matches))) {
            $namedRange = NamedRange::resolveRange($pCoordinate, $this);
            if ($namedRange !== null) {
                $pCoordinate = $namedRange->getRange();
                return $namedRange->getWorksheet()->getCell($pCoordinate, $createIfNotExists);
            }
        }

        // Uppercase coordinate
        $pCoordinate = strtoupper($pCoordinate);

        if (strpos($pCoordinate, ':') !== false || strpos($pCoordinate, ',') !== false) {
            throw new \Exception('Cell coordinate can not be a range of cells.');
        } elseif (strpos($pCoordinate, '$') !== false) {
            throw new \Exception('Cell coordinate must not be absolute.');
        }

        return $createIfNotExists ? $this->createNewCell($pCoordinate) : null;
    }

    /**
     * Create a new cell at the specified coordinate
     *
     * @param string $pCoordinate    Coordinate of the cell
     * @return PHPExcel_Cell Cell that was created
     */
    private function createNewCell($pCoordinate)
    {
        $cell = $this->cellCollection->addCacheData(
            $pCoordinate,
            new Cell(null, DataType::TYPE_NULL, $this)
        );
        $this->cellCollectionIsSorted = false;

        // Coordinates
        $aCoordinates = Cell::coordinateFromString($pCoordinate);
        if (Cell::columnIndexFromString($this->cachedHighestColumn) < Cell::columnIndexFromString($aCoordinates[0])) {
            $this->cachedHighestColumn = $aCoordinates[0];
        }
        $this->cachedHighestRow = max($this->cachedHighestRow, $aCoordinates[1]);

        // Cell needs appropriate xfIndex from dimensions records
        //    but don't create dimension records if they don't already exist
        $rowDimension    = $this->getRowDimension($aCoordinates[1], false);
        $columnDimension = $this->getColumnDimension($aCoordinates[0], false);

        if ($rowDimension !== null && $rowDimension->getXfIndex() > 0) {
            // then there is a row dimension with explicit style, assign it to the cell
            $cell->setXfIndex($rowDimension->getXfIndex());
        } elseif ($columnDimension !== null && $columnDimension->getXfIndex() > 0) {
            // then there is a column dimension, assign it to the cell
            $cell->setXfIndex($columnDimension->getXfIndex());
        }

        return $cell;
    }

    /**
     * Return the cache controller for the cell collection
     *
     * @return PHPExcel_CachedObjectStorage_xxx
     */
    public function getCellCacheController()
    {
        return $this->cellCollection;
    }

    /**
     * 获取工作表总列数
     *
     * @param   string     $row        Return the data highest column for the specified row,
     *                                     or the highest column of any row if no row number is passed
     * @return string Highest column name
     */
    public function getHighestColumn($row = null)
    {
        if ($row == null) {
            return $this->cachedHighestColumn;
        }
        return $this->getHighestDataColumn($row);
    }


    /**
     * 获取工作表指定行的总列数
     *
     * @param   string     $row        Return the highest data column for the specified row,
     *                                     or the highest data column of any row if no row number is passed
     * @return string Highest column name that contains data
     */
    public function getHighestDataColumn($row = null)
    {
        return $this->cellCollection->getHighestColumn($row);
    }

    /**
     * 获取工作表总行数
     *
     * @param   string     $column     Return the highest data row for the specified column,
     *                                     or the highest row of any column if no column letter is passed
     * @return int Highest row number
     */
    public function getHighestRow($column = null)
    {
        if ($column == null) {
            return $this->cachedHighestRow;
        }
        return $this->getHighestDataRow($column);
    }

    /**
     * 获取工作表指定列的总行数
     *
     * @param   string     $column     Return the highest data row for the specified column,
     *                                     or the highest data row of any column if no column letter is passed
     * @return string Highest row number that contains data
     */
    public function getHighestDataRow($column = null)
    {
        return $this->cellCollection->getHighestRow($column);
    }
}