<?php
/**
 * PHPExcel
 *
 * Copyright (c) 2006 - 2013 PHPExcel
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 * @category   PHPExcel
 * @package    PHPExcel_Writer_Excel2007
 * @copyright  Copyright (c) 2006 - 2013 PHPExcel (http://www.codeplex.com/PHPExcel)
 * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt	LGPL
 * @version    1.7.9, 2013-06-02
 */


/**
 * PHPExcel_Writer_Excel2007_Chart
 *
 * @category   PHPExcel
 * @package    PHPExcel_Writer_Excel2007
 * @copyright  Copyright (c) 2006 - 2013 PHPExcel (http://www.codeplex.com/PHPExcel)
 */
class PHPExcel_Writer_Excel2007_Chart extends PHPExcel_Writer_Excel2007_WriterPart
{
	/**
	 * Write charts to XML format
	 *
	 * @param 	PHPExcel_Chart				$pChart
	 * @return 	string 						XML Output
	 * @throws 	PHPExcel_Writer_Exception
	 */
	public function writeChart(PHPExcel_Chart $pChart = null)
	{
		// Create XML writer
		$objWriter = null;
		if ($this->getParentWriter()->getUseDiskCaching()) {
			$objWriter = new PHPExcel_Shared_XMLWriter(PHPExcel_Shared_XMLWriter::STORAGE_DISK, $this->getParentWriter()->getDiskCachingDirectory());
		} else {
			$objWriter = new PHPExcel_Shared_XMLWriter(PHPExcel_Shared_XMLWriter::STORAGE_MEMORY);
		}
		//	Ensure that data series values are up-to-date before we save
		$pChart->refresh();

		// XML header
		$objWriter->startDocument('1.0','UTF-8','yes');

		// c:chartSpace
		$objWriter->startElement('c:chartSpace');
			$objWriter->writeAttribute('xmlns:c', 'http://schemas.openxmlformats.org/drawingml/2006/chart');
			$objWriter->writeAttribute('xmlns:a', 'http://schemas.openxmlformats.org/drawingml/2006/main');
			$objWriter->writeAttribute('xmlns:r', 'http://schemas.openxmlformats.org/officeDocument/2006/relationships');

			$objWriter->startElement('c:date1904');
				$objWriter->writeAttribute('val', 0);
			$objWriter->endElement();
			$objWriter->startElement('c:lang');
				$objWriter->writeAttribute('val', "en-GB");
			$objWriter->endElement();
			$objWriter->startElement('c:roundedCorners');
				$objWriter->writeAttribute('val', 0);
			$objWriter->endElement();

			$this->_writeAlternateContent($objWriter);

			$objWriter->startElement('c:chart');

				$this->_writeTitle($pChart->getTitle(), $objWriter);

				$objWriter->startElement('c:autoTitleDeleted');
					$objWriter->writeAttribute('val', 0);
				$objWriter->endElement();

				$this->_writePlotArea($pChart->getPlotArea(),
									  $pChart->getXAxisLabel(),
									  $pChart->getYAxisLabel(),
									  $objWriter,
									  $pChart->getWorksheet()
									 );

				$this->_writeLegend($pChart->getLegend(), $objWriter);


				$objWriter->startElement('c:plotVisOnly');
					$objWriter->writeAttribute('val', 1);
				$objWriter->endElement();

				$objWriter->startElement('c:dispBlanksAs');
					$objWriter->writeAttribute('val', "gap");
				$objWriter->endElement();

				$objWriter->startElement('c:showDLblsOverMax');
					$objWriter->writeAttribute('val', 0);
				$objWriter->endElement();

			$objWriter->endElement();

			$this->_writePrintSettings($objWriter);

		$objWriter->endElement();

		// Return
		return $objWriter->getData();
	}

	/**
	 * Write Chart Title
	 *
	 * @param	PHPExcel_Chart_Title		$title
	 * @param 	PHPExcel_Shared_XMLWriter 	$objWriter 		XML Writer
	 * @throws 	PHPExcel_Writer_Exception
	 */
	private function _writeTitle(PHPExcel_Chart_Title $title = null, $objWriter)
	{
		if (is_null($title)) {
			return;
		}

		$objWriter->startElement('c:title');
			$objWriter->startElement('c:tx');
				$objWriter->startElement('c:rich');

					$objWriter->startElement('a:bodyPr');
					$objWriter->endElement();

					$objWriter->startElement('a:lstStyle');
					$objWriter->endElement();

					$objWriter->startElement('a:p');

						$caption = $title->getCaption();
						if ((is_array($caption)) && (count($caption) > 0))
							$caption = $caption[0];
						$this->getParentWriter()->getWriterPart('stringtable')->writeRichTextForCharts($objWriter, $caption, 'a');

					$objWriter->endElement();
				$objWriter->endElement();
			$objWriter->endElement();

			$layout = $title->getLayout();
			$this->_writeLayout($layout, $objWriter);

			$objWriter->startElement('c:overlay');
				$objWriter->writeAttribute('val', 0);
			$objWriter->endElement();

		$objWriter->endElement();
	}

	/**
	 * Write Chart Legend
	 *
	 * @param	PHPExcel_Chart_Legend		$legend
	 * @param 	PHPExcel_Shared_XMLWriter 	$objWriter 		XML Writer
	 * @throws 	PHPExcel_Writer_Exception
	 */
	private function _writeLegend(PHPExcel_Chart_Legend $legend = null, $objWriter)
	{
		if (is_null($legend)) {
			return;
		}

		$objWriter->startElement('c:legend');

			$objWriter->startElement('c:legendPos');
				$objWriter->writeAttribute('val', $legend->getPosition());
			$objWriter->endElement();

			$layout = $legend->getLayout();
			$this->_writeLayout($layout, $objWriter);

			$objWriter->startElement('c:overlay');
				$objWriter->writeAttribute('val', ($legend->getOverlay()) ? '1' : '0');
			$objWriter->endElement();

			$objWriter->startElement('c:txPr');
				$objWriter->startElement('a:bodyPr');
				$objWriter->endElement();

				$objWriter->startElement('a:lstStyle');
				$objWriter->endElement();

				$objWriter->startElement('a:p');
					$objWriter->startElement('a:pPr');
						$objWriter->writeAttribute('rtl', 0);

						$objWriter->startElement('a:defRPr');
						$objWriter->endElement();
					$objWriter->endElement();

					$objWriter->startElement('a:endParaRPr');
						$objWriter->writeAttribute('lang', "en-US");
					$objWriter->endElement();

				$objWriter->endElement();
			$objWriter->endElement();

		$objWriter->endElement();
	}

	/**
	 * Write Chart Plot Area
	 *
	 * @param	PHPExcel_Chart_PlotArea		$plotArea
	 * @param	PHPExcel_Chart_Title		$xAxisLabel
	 * @param	PHPExcel_Chart_Title		$yAxisLabel
	 * @param 	PHPExcel_Shared_XMLWriter 	$objWriter 		XML Writer
	 * @throws 	PHPExcel_Writer_Exception
	 */
	private function _writePlotArea(PHPExcel_Chart_PlotArea $plotArea,
									PHPExcel_Chart_Title $xAxisLabel = NULL,
									PHPExcel_Chart_Title $yAxisLabel = NULL,
									$objWriter,
									PHPExcel_Worksheet $pSheet)
	{
		if (is_null($plotArea)) {
			return;
		}

		$id1 = $id2 = 0;
		$this->_seriesIndex = 0;
		$objWriter->startElement('c:plotArea');

			$layout = $plotArea->getLayout();

			$this->_writeLayout($layout, $objWriter);

			$chartTypes = self::_getChartType($plotArea);
			$catIsMultiLevelSeries = $valIsMultiLevelSeries = FALSE;
			$plotGroupingType = '';
			foreach($chartTypes as $chartType) {
				$objWriter->startElement('c:'.$chartType);

					$groupCount = $plotArea->getPlotGroupCount();
					for($i = 0; $i < $groupCount; ++$i) {
						$plotGroup = $plotArea->getPlotGroupByIndex($i);
						$groupType = $plotGroup->getPlotType();
						if ($groupType == $chartType) {

							$plotStyle = $plotGroup->getPlotStyle();
							if ($groupType === PHPExcel_Chart_DataSeries::TYPE_RADARCHART) {
								$objWriter->startElement('c:radarStyle');
									$objWriter->writeAttribute('val', $plotStyle );
								$objWriter->endElement();
							} elseif ($groupType === PHPExcel_Chart_DataSeries::TYPE_SCATTERCHART) {
								$objWriter->startElement('c:scatterStyle');
									$objWriter->writeAttribute('val', $plotStyle );
								$objWriter->endElement();
							}

							$this->_writePlotGroup($plotGroup, $chartType, $objWriter, $catIsMultiLevelSeries, $valIsMultiLevelSeries, $plotGroupingType, $pSheet);
						}
					}

					$this->_writeDataLbls($objWriter, $layout);

					if ($chartType === PHPExcel_Chart_DataSeries::TYPE_LINECHART) {
						//	Line only, Line3D can't be smoothed

						$objWriter->startElement('c:smooth');
							$objWriter->writeAttribute('val', (integer) $plotGroup->getSmoothLine() );
						$objWriter->endElement();
					} elseif (($chartType === PHPExcel_Chart_DataSeries::TYPE_BARCHART) ||
						($chartType === PHPExcel_Chart_DataSeries::TYPE_BARCHART_3D)) {

						$objWriter->startElement('c:gapWidth');
							$objWriter->writeAttribute('val', 150 );
						$objWriter->endElement();

						if ($plotGroupingType == 'percentStacked' ||
							$plotGroupingType == 'stacked') {

							$objWriter->startElement('c:overlap');
								$objWriter->writeAttribute('val', 100 );
							$objWriter->endElement();
						}
					} elseif ($chartType === PHPExcel_Chart_DataSeries::TYPE_BUBBLECHART) {

							$objWriter->startElement('c:bubbleScale');
								$objWriter->writeAttribute('val', 25 );
							$objWriter->endElement();

							$objWriter->startElement('c:showNegBubbles');
								$objWriter->writeAttribute('val', 0 );
							$objWriter->endElement();
					} elseif ($chartType === PHPExcel_Chart_DataSeries::TYPE_STOCKCHART) {

							$objWriter->startElement('c:hiLowLines');
							$objWriter->endElement();
					}

					//	Generate 2 unique numbers to use for axId values
//					$id1 = $id2 = rand(10000000,99999999);
//					do {
//						$id2 = rand(10000000,99999999);
//					} while ($id1 == $id2);
					$id1 = '75091328';
					$id2 = '75089408';

					if (($chartType !== PHPExcel_Chart_DataSeries::TYPE_PIECHART) &&
						($chartType !== PHPExcel_Chart_DataSeries::TYPE_PIECHART_3D) &&
						($chartType !== PHPExcel_Chart_DataSeries::TYPE_DONUTCHART)) {

						$objWriter->startElement('c:axId');
							$objWriter->writeAttribute('val', $id1 );
						$objWriter->endElement();
						$objWriter->startElement('c:axId');
							$objWriter->writeAttribute('val', $id2 );
						$objWriter->endElement();
					} else {
						$objWriter->startElement('c:firstSliceAng');
							$objWriter->writeAttribute('val', 0);
						$objWriter->endElement();

						if ($chartType === PHPExcel_Chart_DataSeries::TYPE_DONUTCHART) {

							$objWriter->startElement('c:holeSize');
								$objWriter->writeAttribute('val', 50);
							$objWriter->endElement();
						}
					}

				$objWriter->endElement();
			}

			if (($chartType !== PHPExcel_Chart_DataSeries::TYPE_PIECHART) &&
				($chartType !== PHPExcel_Chart_DataSeries::TYPE_PIECHART_3D) &&
				($chartType !== PHPExcel_Chart_DataSeries::TYPE_DONUTCHART)) {

				if ($chartType === PHPExcel_Chart_DataSeries::TYPE_BUBBLECHART) {
					$this->_writeValAx($objWriter,$plotArea,$xAxisLabel,$chartType,$id1,$id2,$catIsMultiLevelSeries);
				} else {
					$this->_writeCatAx($objWriter,$plotArea,$xAxisLabel,$chartType,$id1,$id2,$catIsMultiLevelSeries);
				}

				$this->_writeValAx($objWriter,$plotArea,$yAxisLabel,$chartType,$id1,$id2,$valIsMultiLevelSeries);
			}

		$objWriter->endElement();
	}

	/**
	 * Write Data Labels
	 *
	 * @param 	PHPExcel_Shared_XMLWriter 	$objWriter 		XML Writer
	 * @param 	PHPExcel_Chart_Layout		$chartLayout	Chart layout
	 * @throws 	PHPExcel_Writer_Exception
	 */
	private function _writeDataLbls($objWriter, $chartLayout)
	{
		$objWriter->startElement('c:dLbls');

			$objWriter->startElement('c:showLegendKey');
				$showLegendKey = (empty($chartLayout)) ? 0 : $chartLayout->getShowLegendKey();
				$objWriter->writeAttribute('val', ((empty($showLegendKey)) ? 0 : 1) );
			$objWriter->endElement();


			$objWriter->startElement('c:showVal');
				$showVal = (empty($chartLayout)) ? 0 : $chartLayout->getShowVal();
				$objWriter->writeAttribute('val', ((empty($showVal)) ? 0 : 1) );
			$objWriter->endElement();

			$objWriter->startElement('c:showCatName');
				$showCatName = (empty($chartLayout)) ? 0 : $chartLayout->getShowCatName();
				$objWriter->writeAttribute('val', ((empty($showCatName)) ? 0 : 1) );
			$objWriter->endElement();

			$objWriter->startElement('c:showSerName');
				$showSerName = (empty($chartLayout)) ? 0 : $chartLayout->getShowSerName();
				$objWriter->writeAttribute('val', ((empty($showSerName)) ? 0 : 1) );
			$objWriter->endElement();

			$objWriter->startElement('c:showPercent');
				$showPercent = (empty($chartLayout)) ? 0 : $chartLayout->getShowPercent();
				$objWriter->writeAttribute('val', ((empty($showPercent)) ? 0 : 1) );
			$objWriter->endElement();

			$objWriter->startElement('c:showBubbleSize');
				$showBubbleSize = (empty($chartLayout)) ? 0 : $chartLayout->getShowBubbleSize();
				$objWriter->writeAttribute('val', ((empty($showBubbleSize)) ? 0 : 1) );
			$objWriter->endElement();

			$objWriter->startElement('c:showLeaderLines');
				$showLeaderLines = (empty($chartLayout)) ? 1 : $chartLayout->getShowLeaderLines();
				$objWriter->writeAttribute('val', ((empty($showLeaderLines)) ? 0 : 1) );
			$objWriter->endElement();

		$objWriter->endElement();
	}

	/**
	 * Write Category Axis
	 *
	 * @param 	PHPExcel_Shared_XMLWriter 	$objWriter 		XML Writer
	 * @param 	PHPExcel_Chart_PlotArea		$plotArea
	 * @param 	PHPExcel_Chart_Title		$xAxisLabel
	 * @param 	string						$groupType		Chart type
	 * @param 	string						$id1
	 * @param 	string						$id2
	 * @param 	boolean						$isMultiLevelSeries
	 * @throws 	PHPExcel_Writer_Exception
	 */
	private function _writeCatAx($objWriter, PHPExcel_Chart_PlotArea $plotArea, $xAxisLabel, $groupType, $id1, $id2, $isMultiLevelSeries)
	{
		$objWriter->startElement('c:catAx');

			if ($id1 > 0) {
				$objWriter->startElement('c:axId');
					$objWriter->writeAttribute('val', $id1);
				$objWriter->endElement();
			}

			$objWriter->startElement('c:scaling');
				$objWriter->startElement('c:orientation');
					$objWriter->writeAttribute('val', "minMax");
				$objWriter->endElement();
			$objWriter->endElement();

			$objWriter->startElement('c:delete');
				$objWriter->writeAttribute('val', 0);
			$objWriter->endElement();

			$objWriter->startElement('c:axPos');
				$objWriter->writeAttribute('val', "b");
			$objWriter->endElement();

			if (!is_null($xAxisLabel)) {
				$objWriter->startElement('c:title');
					$objWriter->startElement('c:tx');
						$objWriter->startElement('c:rich');

							$objWriter->startElement('a:bodyPr');
							$objWriter->endElement();

							$objWriter->startElement('a:lstStyle');
							$objWriter->endElement();

							$objWriter->startElement('a:p');
								$objWriter->startElement('a:r');

									$caption = $xAxisLabel->getCaption();
									if (is_array($caption))
										$caption = $caption[0];
									$objWriter->startElement('a:t');
//										$objWriter->writeAttribute('xml:space', 'preserve');
										$objWriter->writeRawData(PHPExcel_Shared_String::ControlCharacterPHP2OOXML( $caption ));
									$objWriter->endElement();

								$objWriter->endElement();
							$objWriter->endElement();
						$objWriter->endElement();
					$objWriter->endElement();

					$layout = $xAxisLabel->getLayout();
					$this->_writeLayout($layout, $objWriter);

					$objWriter->startElement('c:overlay');
						$objWriter->writeAttribute('val', 0);
					$objWriter->endElement();

				$objWriter->endElement();

			}

			$objWriter->startElement('c:numFmt');
				$objWriter->writeAttribute('formatCode', "General");
				$objWriter->writeAttribute('sourceLinked', 1);
			$objWriter->endElement();

			$objWriter->startElement('c:majorTickMark');
				$objWriter->writeAttribute('val', "out");
			$objWriter->endElement();

			$objWriter->startElement('c:minorTickMark');
				$objWriter->writeAttribute('val', "none");
			$objWriter->endElement();

			$objWriter->startElement('c:tickLblPos');
				$objWriter->writeAttribute('val', "nextTo");
			$objWriter->endElement();

			if ($id2 > 0) {
					$objWriter->startElement('c:crossAx');
						$objWriter->writeAttribute('val', $id2);
					$objWriter->endElement();

					$objWriter->startElement('c:crosses');
						$objWriter->writeAttribute('val', "autoZero");
					$objWriter->endElement();
			}

			$objWriter->startElement('c:auto');
				$objWriter->writeAttribute('val', 1);
			$objWriter->endElement();

			$objWriter->startElement('c:lblAlgn');
				$objWriter->writeAttribute('val', "ctr");
			$objWriter->endElement();

			$objWriter->startElement('c:lblOffset');
				$objWriter->writeAttribute('val', 100);
			$objWriter->endElement();

			if ($isMultiLevelSeries) {
				$objWriter->startElement('c:noMultiLvlLbl');
					$objWriter->writeAttribute('val', 0);
				$objWriter->endElement();
			}
		$objWriter->endElement();

	}


	/**
	 * Write Value Axis
	 *
	 * @param 	PHPExcel_Shared_XMLWriter 	$objWriter 		XML Writer
	 * @param 	PHPExcel_Chart_PlotArea		$plotArea
	 * @param 	PHPExcel_Chart_Title		$yAxisLabel
	 * @param 	string						$groupType		Chart type
	 * @param 	string						$id1
	 * @param 	string						$id2
	 * @param 	boolean						$isMultiLevelSeries
	 * @throws 	PHPExcel_Writer_Exception
	 */
	private function _writeValAx($objWriter, PHPExcel_Chart_PlotArea $plotArea, $yAxisLabel, $groupType, $id1, $id2, $isMultiLevelSeries)
	{
		$objWriter->startElement('c:valAx');

			if ($id2 > 0) {
				$objWriter->startElement('c:axId');
					$objWriter->writeAttribute('val', $id2);
				$objWriter->endElement();
			}

			$objWriter->startElement('c:scaling');
				$objWriter->startElement('c:orientation');
					$objWriter->writeAttribute('val', "minMax");
				$objWriter->endElement();
			$objWriter->endElement();

			$objWriter->startElement('c:delete');
				$objWriter->writeAttribute('val', 0);
			$objWriter->endElement();

			$objWriter->startElement('c:axPos');
				$objWriter->writeAttribute('val', "l");
			$objWriter->endElement();

			$objWriter->startElement('c:majorGridlines');
			$objWriter->endElement();

			if (!is_null($yAxisLabel)) {
				$objWriter->startElement('c:title');
					$objWriter->startElement('c:tx');
						$objWriter->startElement('c:rich');

							$objWriter->startElement('a:bodyPr');
							$objWriter->endElement();

							$objWriter->startElement('a:lstStyle');
							$objWriter->endElement();

							$objWriter->startElement('a:p');
								$objWriter->startElement('a:r');

									$caption = $yAxisLabel->getCaption();
									if (is_array($caption))
										$caption = $caption[0];
									$objWriter->startElement('a:t');
//										$objWriter->writeAttribute('xml:space', 'preserve');
										$objWriter->writeRawData(PHPExcel_Shared_String::ControlCharacterPHP2OOXML( $caption ));
									$objWriter->endElement();

								$objWriter->endElement();
							$objWriter->endElement();
						$objWriter->endElement();
					$objWriter->endElement();

					if ($groupType !== PHPExcel_Chart_DataSeries::TYPE_BUBBLECHART) {
						$layout = $yAxisLabel->getLayout();
						$this->_writeLayout($layout, $objWriter);
					}

					$objWriter->startElement('c:overlay');
						$objWriter->writeAttribute('val', 0);
					$objWriter->endElement();

				$objWriter->endElement();
			}

			$objWriter->startElement('c:numFmt');
				$objWriter->writeAttribute('formatCode', "General");
				$objWriter->writeAttribute('sourceLinked', 1);
			$objWriter->endElement();

			$objWriter->startElement('c:majorTickMark');
				$objWriter->writeAttribute('val', "out");
			$objWriter->endElement();

			$objWriter->startElement('c:minorTickMark');
				$objWriter->writeAttribute('val', "none");
			$objWriter->endElement();

			$objWriter->startElement('c:tickLblPos');
				$objWriter->writeAttribute('val', "nextTo");
			$objWriter->endElement();

			if ($id1 > 0) {
					$objWriter->startElement('c:crossAx');
						$objWriter->writeAttribute('val', $id2);
					$objWriter->endElement();

					$objWriter->startElement('c:crosses');
						$objWriter->writeAttribute('val', "autoZero");
					$objWriter->endElement();

					$objWriter->startElement('c:crossBetween');
						$objWriter->writeAttribute('val', "midCat");
					$objWriter->endElement();
			}

			if ($isMultiLevelSeries) {
				if ($groupType !== PHPExcel_Chart_DataSeries::TYPE_BUBBLECHART) {
					$objWriter->startElement('c:noMultiLvlLbl');
						$objWriter->writeAttribute('val', 0);
					$objWriter->endElement();
				}
			}
		$objWriter->endElement();

	}


	/**
	 * Get the data series type(s) for a chart plot series
	 *
	 * @param 	PHPExcel_Chart_PlotArea		$plotArea
	 * @return	string|array
	 * @throws 	PHPExcel_Writer_Exception
	 */
	private static function _getChartType($plotArea)
	{
		$groupCount = $plotArea->getPlotGroupCount();

		if ($groupCount == 1) {
			$chartType = array($plotArea->getPlotGroupByIndex(0)->getPlotType());
		} else {
			$chartTypes = array();
			for($i = 0; $i < $groupCount; ++$i) {
				$chartTypes[] = $plotArea->getPlotGroupByIndex($i)->getPlotType();
			}
			$chartType = array_unique($chartTypes);
			if (count($chartTypes) == 0) {
				throw new PHPExcel_Writer_Exception('Chart is not yet implemented');
			}
		}

		return $chartType;
	}

	/**
	 * Write Plot Group (series of related plots)
	 *
	 * @param	PHPExcel_Chart_DataSeries		$plotGroup
	 * @param	string							$groupType				Type of plot for dataseries
	 * @param 	PHPExcel_Shared_XMLWriter 		$objWriter 				XML Writer
	 * @param	boolean							&$catIsMultiLevelSeries	Is category a multi-series category
	 * @param	boolean							&$valIsMultiLevelSeries	Is value set a multi-series set
	 * @param	string							&$plotGroupingType		Type of grouping for multi-series values
	 * @param	PHPExcel_Worksheet 				$pSheet
	 * @throws 	PHPExcel_Writer_Exception
	 */
	private function _writePlotGroup( $plotGroup,
									  $groupType,
									  $objWriter,
									  &$catIsMultiLevelSeries,
									  &$valIsMultiLevelSeries,
									  &$plotGroupingType,
									  PHPExcel_Worksheet $pSheet
									)
	{
		if (is_null($plotGroup)) {
			return;
		}

		if (($groupType == PHPExcel_Chart_DataSeries::TYPE_BARCHART) ||
			($groupType == PHPExcel_Chart_DataSeries::TYPE_BARCHART_3D)) {
			$objWriter->startElement('c:barDir');
				$objWriter->writeAttribute('val', $plotGroup->getPlotDirection());
			$objWriter->endElement();
		}

		if (!is_null($plotGroup->getPlotGrouping())) {
			$plotGroupingType = $plotGroup->getPlotGrouping();
			$objWriter->startElement('c:grouping');
				$objWriter->writeAttribute('val', $plotGroupingType);
			$objWriter->endElement();
		}

		//	Get these details before the loop, because we can use the count to check for varyColors
		$plotSeriesOrder = $plotGroup->getPlotOrder();
		$plotSeriesCount = count($plotSeriesOrder);

		if (($groupType !== PHPExcel_Chart_DataSeries::TYPE_RADARCHART) &&
			($groupType !== PHPExcel_Chart_DataSeries::TYPE_STOCKCHART)) {

			if ($groupType !== PHPExcel_Chart_DataSeries::TYPE_LINECHART) {
				if (($groupType == PHPExcel_Chart_DataSeries::TYPE_PIECHART) ||
					($groupType == PHPExcel_Chart_DataSeries::TYPE_PIECHART_3D) ||
					($groupType == PHPExcel_Chart_DataSeries::TYPE_DONUTCHART) ||
					($plotSeriesCount > 1)) {
					$objWriter->startElement('c:varyColors');
						$objWriter->writeAttribute('val', 1);
					$objWriter->endElement();
				} else {
					$objWriter->startElement('c:varyColors');
						$objWriter->writeAttribute('val', 0);
					$objWriter->endElement();
				}
			}
		}

		foreach($plotSeriesOrder as $plotSeriesIdx => $plotSeriesRef) {
			$objWriter->startElement('c:ser');

				$objWriter->startElement('c:idx');
					$objWriter->writeAttribute('val', $this->_seriesIndex + $plotSeriesIdx);
				$objWriter->endElement();

				$objWriter->startElement('c:order');
					$objWriter->writeAttribute('val', $this->_seriesIndex + $plotSeriesRef);
				$objWriter->endElement();

				if (($groupType == PHPExcel_Chart_DataSeries::TYPE_PIECHART) ||
					($groupType == PHPExcel_Chart_DataSeries::TYPE_PIECHART_3D) ||
					($groupType == PHPExcel_Chart_DataSeries::TYPE_DONUTCHART)) {

					$objWriter->startElement('c:dPt');
						$objWriter->startElement('c:idx');
							$objWriter->writeAttribute('val', 3);
						$objWriter->endElement();

						$objWriter->startElement('c:bubble3D');
							$objWriter->writeAttribute('val', 0);
						$objWriter->endElement();

						$objWriter->startElement('c:spPr');
							$objWriter->startElement('a:solidFill');
								$objWriter->startElement('a:srgbClr');
									$objWriter->writeAttribute('val', 'FF9900');
								$objWriter->endElement();
							$objWriter->endElement();
						$objWriter->endElement();
					$objWriter->endElement();
				}

				//	Labels
				$plotSeriesLabel = $plotGroup->getPlotLabelByIndex($plotSeriesRef);
				if ($plotSeriesLabel && ($plotSeriesLabel->getPointCount() > 0)) {
					$objWriter->startElement('c:tx');
						$objWriter->startElement('c:strRef');
							$this->_writePlotSeriesLabel($plotSeriesLabel, $objWriter);
						$objWriter->endElement();
					$objWriter->endElement();
				}

				//	Formatting for the points
				if ($groupType == PHPExcel_Chart_DataSeries::TYPE_LINECHART) {
					$objWriter->startElement('c:spPr');
						$objWriter->startElement('a:ln');
							$objWriter->writeAttribute('w', 12700);
						$objWriter->endElement();
					$objWriter->endElement();
				}

				$plotSeriesValues = $plotGroup->getPlotValuesByIndex($plotSeriesRef);
				if ($plotSeriesValues) {
					$plotSeriesMarker = $plotSeriesValues->getPointMarker();
					if ($plotSeriesMarker) {
						$objWriter->startElement('c:marker');
							$objWriter->startElement('c:symbol');
								$objWriter->writeAttribute('val', $plotSeriesMarker);
							$objWriter->endElement();

							if ($plotSeriesMarker !== 'none') {
								$objWriter->startElement('c:size');
									$objWriter->writeAttribute('val', 3);
								$objWriter->endElement();
							}
						$objWriter->endElement();
					}
				}

				if (($groupType === PHPExcel_Chart_DataSeries::TYPE_BARCHART) ||
					($groupType === PHPExcel_Chart_DataSeries::TYPE_BARCHART_3D) ||
					($groupType === PHPExcel_Chart_DataSeries::TYPE_BUBBLECHART)) {

					$objWriter->startElement('c:invertIfNegative');
						$objWriter->writeAttribute('val', 0);
					$objWriter->endElement();
				}

				//	Category Labels
				$plotSeriesCategory = $plotGroup->getPlotCategoryByIndex($plotSeriesRef);
				if ($plotSeriesCategory && ($plotSeriesCategory->getPointCount() > 0)) {
					$catIsMultiLevelSeries = $catIsMultiLevelSeries || $plotSeriesCategory->isMultiLevelSeries();

					if (($groupType == PHPExcel_Chart_DataSeries::TYPE_PIECHART) ||
						($groupType == PHPExcel_Chart_DataSeries::TYPE_PIECHART_3D) ||
						($groupType == PHPExcel_Chart_DataSeries::TYPE_DONUTCHART)) {

						if (!is_null($plotGroup->getPlotStyle())) {
							$plotStyle = $plotGroup->getPlotStyle();
							if ($plotStyle) {
								$objWriter->startElement('c:explosion');
									$objWriter->writeAttribute('val', 25);
								$objWriter->endElement();
							}
						}
					}

					if (($groupType === PHPExcel_Chart_DataSeries::TYPE_BUBBLECHART) ||
						($groupType === PHPExcel_Chart_DataSeries::TYPE_SCATTERCHART)) {
						$objWriter->startElement('c:xVal');
					} else {
						$objWriter->startElement('c:cat');
					}

						$this->_writePlotSeriesValues($plotSeriesCategory, $objWriter, $groupType, 'str', $pSheet);
					$objWriter->endElement();
				}

				//	Values
				if ($plotSeriesValues) {
					$valIsMultiLevelSeries = $valIsMultiLevelSeries || $plotSeriesValues->isMultiLevelSeries();

					if (($groupType === PHPExcel_Chart_DataSeries::TYPE_BUBBLECHART) ||
						($groupType === PHPExcel_Chart_DataSeries::TYPE_SCATTERCHART)) {
						$objWriter->startElement('c:yVal');
					} else {
						$objWriter->startElement('c:val');
					}

						$this->_writePlotSeriesValues($plotSeriesValues, $objWriter, $groupType, 'num', $pSheet);
					$objWriter->endElement();
				}

				if ($groupType === PHPExcel_Chart_DataSeries::TYPE_BUBBLECHART) {
					$this->_writeBubbles($plotSeriesValues, $objWriter, $pSheet);
				}

			$objWriter->endElement();

		}

		$this->_seriesIndex += $plotSeriesIdx + 1;
	}

	/**
	 * Write Plot Series Label
	 *
	 * @param	PHPExcel_Chart_DataSeriesValues		$plotSeriesLabel
	 * @param 	PHPExcel_Shared_XMLWriter 			$objWriter 			XML Writer
	 * @throws 	PHPExcel_Writer_Exception
	 */
	private function _writePlotSeriesLabel($plotSeriesLabel, $objWriter)
	{
		if (is_null($plotSeriesLabel)) {
			return;
		}

		$objWriter->startElement('c:f');
			$objWriter->writeRawData($plotSeriesLabel->getDataSource());
		$objWriter->endElement();

		$objWriter->startElement('c:strCache');
			$objWriter->startElement('c:ptCount');
				$objWriter->writeAttribute('val', $plotSeriesLabel->getPointCount() );
			$objWriter->endElement();

			foreach($plotSeriesLabel->getDataValues() as $plotLabelKey => $plotLabelValue) {
				$objWriter->startElement('c:pt');
					$objWriter->writeAttribute('idx', $plotLabelKey );

					$objWriter->startElement('c:v');
						$objWriter->writeRawData( $plotLabelValue );
					$objWriter->endElement();
				$objWriter->endElement();
			}
		$objWriter->endElement();

	}

	/**
	 * Write Plot Series Values
	 *
	 * @param	PHPExcel_Chart_DataSeriesValues		$plotSeriesValues
	 * @param 	PHPExcel_Shared_XMLWriter 			$objWriter 			XML Writer
	 * @param	string								$groupType			Type of plot for dataseries
	 * @param	string								$dataType			Datatype of series values
	 * @param	PHPExcel_Worksheet 					$pSheet
	 * @throws 	PHPExcel_Writer_Exception
	 */
	private function _writePlotSeriesValues( $plotSeriesValues,
											 $objWriter,
											 $groupType,
											 $dataType='str',
											 PHPExcel_Worksheet $pSheet
										   )
	{
		if (is_null($plotSeriesValues)) {
			return;
		}

		if ($plotSeriesValues->isMultiLevelSeries()) {
			$levelCount = $plotSeriesValues->multiLevelCount();

			$objWriter->startElement('c:multiLvlStrRef');

				$objWriter->startElement('c:f');
					$objWriter->writeRawData( $plotSeriesValues->getDataSource() );
				$objWriter->endElement();

				$objWriter->startElement('c:multiLvlStrCache');

					$objWriter->startElement('c:ptCount');
						$objWriter->writeAttribute('val', $plotSeriesValues->getPointCount() );
					$objWriter->endElement();

					for ($level = 0; $level < $levelCount; ++$level) {
						$objWriter->startElement('c:lvl');

						foreach($plotSeriesValues->getDataValues() as $plotSeriesKey => $plotSeriesValue) {
							if (isset($plotSeriesValue[$level])) {
								$objWriter->startElement('c:pt');
									$objWriter->writeAttribute('idx', $plotSeriesKey );

									$objWriter->startElement('c:v');
										$objWriter->writeRawData( $plotSeriesValue[$level] );
									$objWriter->endElement();
								$objWriter->endElement();
							}
						}

						$objWriter->endElement();
					}

				$objWriter->endElement();

			$objWriter->endElement();
		} else {
			$objWriter->startElement('c:'.$dataType.'Ref');

				$objWriter->startElement('c:f');
					$objWriter->writeRawData( $plotSeriesValues->getDataSource() );
				$objWriter->endElement();

				$objWriter->startElement('c:'.$dataType.'Cache');

					if (($groupType != PHPExcel_Chart_DataSeries::TYPE_PIECHART) &&
						($groupType != PHPExcel_Chart_DataSeries::TYPE_PIECHART_3D) &&
						($groupType != PHPExcel_Chart_DataSeries::TYPE_DONUTCHART)) {

						if (($plotSeriesValues->getFormatCode() !== NULL) &&
							($plotSeriesValues->getFormatCode() !== '')) {
							$objWriter->startElement('c:formatCode');
								$objWriter->writeRawData( $plotSeriesValues->getFormatCode() );
							$objWriter->endElement();
						}
					}

					$objWriter->startElement('c:ptCount');
						$objWriter->writeAttribute('val', $plotSeriesValues->getPointCount() );
					$objWriter->endElement();

					$dataValues = $plotSeriesValues->getDataValues();
					if (!empty($dataValues)) {
						if (is_array($dataValues)) {
							foreach($dataValues as $plotSeriesKey => $plotSeriesValue) {
								$objWriter->startElement('c:pt');
									$objWriter->writeAttribute('idx', $plotSeriesKey );

									$objWriter->startElement('c:v');
										$objWriter->writeRawData( $plotSeriesValue );
									$objWriter->endElement();
								$objWriter->endElement();
							}
						}
					}

				$objWriter->endElement();

			$objWriter->endElement();
		}
	}

	/**
	 * Write Bubble Chart Details
	 *
	 * @param	PHPExcel_Chart_DataSeriesValues		$plotSeriesValues
	 * @param 	PHPExcel_Shared_XMLWriter 			$objWriter 			XML Writer
	 * @throws 	PHPExcel_Writer_Exception
	 */
	private function _writeBubbles($plotSeriesValues, $objWriter, PHPExcel_Worksheet $pSheet)
	{
		if (is_null($plotSeriesValues)) {
			return;
		}

		$objWriter->startElement('c:bubbleSize');
			$objWriter->startElement('c:numLit');

				$objWriter->startElement('c:formatCode');
					$objWriter->writeRawData( 'General' );
				$objWriter->endElement();

				$objWriter->startElement('c:ptCount');
					$objWriter->writeAttribute('val', $plotSeriesValues->getPointCount() );
				$objWriter->endElement();

				$dataValues = $plotSeriesValues->getDataValues();
				if (!empty($dataValues)) {
					if (is_array($dataValues)) {
						foreach($dataValues as $plotSeriesKey => $plotSeriesValue) {
							$objWriter->startElement('c:pt');
								$objWriter->writeAttribute('idx', $plotSeriesKey );
								$objWriter->startElement('c:v');
									$objWriter->writeRawData( 1 );
								$objWriter->endElement();
							$objWriter->endElement();
						}
					}
				}

			$objWriter->endElement();
		$objWriter->endElement();

		$objWriter->startElement('c:bubble3D');
			$objWriter->writeAttribute('val', 0 );
		$objWriter->endElement();
	}

	/**
	 * Write Layout
	 *
	 * @param	PHPExcel_Chart_Layout		$layout
	 * @param 	PHPExcel_Shared_XMLWriter 	$objWriter 		XML Writer
	 * @throws 	PHPExcel_Writer_Exception
	 */
	private function _writeLayout(PHPExcel_Chart_Layout $layout = NULL, $objWriter)
	{
		$objWriter->startElement('c:layout');

			if (!is_null($layout)) {
				$objWriter->startElement('c:manualLayout');

					$layoutTarget = $layout->getLayoutTarget();
					if (!is_null($layoutTarget)) {
						$objWriter->startElement('c:layoutTarget');
							$objWriter->writeAttribute('val', $layoutTarget);
						$objWriter->endElement();
					}

					$xMode = $layout->getXMode();
					if (!is_null($xMode)) {
						$objWriter->startElement('c:xMode');
							$objWriter->writeAttribute('val', $xMode);
						$objWriter->endElement();
					}

					$yMode = $layout->getYMode();
					if (!is_null($yMode)) {
						$objWriter->startElement('c:yMode');
							$objWriter->writeAttribute('val', $yMode);
						$objWriter->endElement();
					}

					$x = $layout->getXPosition();
					if (!is_null($x)) {
						$objWriter->startElement('c:x');
							$objWriter->writeAttribute('val', $x);
						$objWriter->endElement();
					}

					$y = $layout->getYPosition();
					if (!is_null($y)) {
						$objWriter->startElement('c:y');
							$objWriter->writeAttribute('val', $y);
						$objWriter->endElement();
					}

					$w = $layout->getWidth();
					if (!is_null($w)) {
						$objWriter->startElement('c:w');
							$objWriter->writeAttribute('val', $w);
						$objWriter->endElement();
					}

					$h = $layout->getHeight();
					if (!is_null($h)) {
						$objWriter->startElement('c:h');
							$objWriter->writeAttribute('val', $h);
						$objWriter->endElement();
					}

				$objWriter->endElement();
			}

		$objWriter->endElement();
	}

	/**
	 * Write Alternate Content block
	 *
	 * @param 	PHPExcel_Shared_XMLWriter 	$objWriter 		XML Writer
	 * @throws 	PHPExcel_Writer_Exception
	 */
	private function _writeAlternateContent($objWriter)
	{
		$objWriter->startElement('mc:AlternateContent');
			$objWriter->writeAttribute('xmlns:mc', 'http://schemas.openxmlformats.org/markup-compatibility/2006');

			$objWriter->startElement('mc:Choice');
				$objWriter->writeAttribute('xmlns:c14', 'http://schemas.microsoft.com/office/drawing/2007/8/2/chart');
				$objWriter->writeAttribute('Requires', 'c14');

				$objWriter->startElement('c14:style');
					$objWriter->writeAttribute('val', '102');
				$objWriter->endElement();
			$objWriter->endElement();

			$objWriter->startElement('mc:Fallback');
				$objWriter->startElement('c:style');
					$objWriter->writeAttribute('val', '2');
				$objWriter->endElement();
			$objWriter->endElement();

		$objWriter->endElement();
	}

	/**
	 * Write Printer Settings
	 *
	 * @param 	PHPExcel_Shared_XMLWriter 	$objWriter 		XML Writer
	 * @throws 	PHPExcel_Writer_Exception
	 */
	private function _writePrintSettings($objWriter)
	{
		$objWriter->startElement('c:printSettings');

			$objWriter->startElement('c:headerFooter');
			$objWriter->endElement();

			$objWriter->startElement('c:pageMargins');
				$objWriter->writeAttribute('footer', 0.3);
				$objWriter->writeAttribute('header', 0.3);
				$objWriter->writeAttribute('r', 0.7);
				$objWriter->writeAttribute('l', 0.7);
				$objWriter->writeAttribute('t', 0.75);
				$objWriter->writeAttribute('b', 0.75);
			$objWriter->endElement();

			$objWriter->startElement('c:pageSetup');
				$objWriter->writeAttribute('orientation', "portrait");
			$objWriter->endElement();

		$objWriter->endElement();
	}

}
