<?php

/**

 * PHPExcel

 *

 * Copyright (c) 2006 - 2014 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_Calculation

 * @copyright  Copyright (c) 2006 - 2014 PHPExcel (http://www.codeplex.com/PHPExcel)

 * @license	http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt	LGPL

 * @version	##VERSION##, ##DATE##

 */



/**

 * PHPExcel_CalcEngine_Logger

 *

 * @category	PHPExcel

 * @package		PHPExcel_Calculation

 * @copyright	Copyright (c) 2006 - 2014 PHPExcel (http://www.codeplex.com/PHPExcel)

 */

class PHPExcel_CalcEngine_Logger {



	/**

	 * Flag to determine whether a debug log should be generated by the calculation engine

	 *		If true, then a debug log will be generated

	 *		If false, then a debug log will not be generated

	 *

	 * @var boolean

	 */

	private $_writeDebugLog = FALSE;



	/**

	 * Flag to determine whether a debug log should be echoed by the calculation engine

	 *		If true, then a debug log will be echoed

	 *		If false, then a debug log will not be echoed

	 * A debug log can only be echoed if it is generated

	 *

	 * @var boolean

	 */

	private $_echoDebugLog = FALSE;



	/**

	 * The debug log generated by the calculation engine

	 *

	 * @var string[]

	 */

	private $_debugLog = array();



	/**

	 * The calculation engine cell reference stack

	 *

	 * @var PHPExcel_CalcEngine_CyclicReferenceStack

	 */

	private $_cellStack;



	

	/**

	 * Instantiate a Calculation engine logger

	 *

	 * @param  PHPExcel_CalcEngine_CyclicReferenceStack $stack

	 */

	public function __construct(PHPExcel_CalcEngine_CyclicReferenceStack $stack) {

		$this->_cellStack = $stack;

	}



	/**

	 * Enable/Disable Calculation engine logging

	 *

	 * @param  boolean $pValue

	 */

	public function setWriteDebugLog($pValue = FALSE) {

		$this->_writeDebugLog = $pValue;

	}



	/**

	 * Return whether calculation engine logging is enabled or disabled

	 *

	 * @return  boolean

	 */

	public function getWriteDebugLog() {

		return $this->_writeDebugLog;

	}



	/**

	 * Enable/Disable echoing of debug log information

	 *

	 * @param  boolean $pValue

	 */

	public function setEchoDebugLog($pValue = FALSE) {

		$this->_echoDebugLog = $pValue;

	}



	/**

	 * Return whether echoing of debug log information is enabled or disabled

	 *

	 * @return  boolean

	 */

	public function getEchoDebugLog() {

		return $this->_echoDebugLog;

	}



	/**

	 * Write an entry to the calculation engine debug log

	 */

	public function writeDebugLog() {

		//	Only write the debug log if logging is enabled

		if ($this->_writeDebugLog) {

			$message = implode(func_get_args());

			$cellReference = implode(' -> ', $this->_cellStack->showStack());

			if ($this->_echoDebugLog) {

				echo $cellReference, 

					($this->_cellStack->count() > 0 ? ' => ' : ''), 

					$message, 

					PHP_EOL;

			}

			$this->_debugLog[] = $cellReference . 

				($this->_cellStack->count() > 0 ? ' => ' : '') . 

				$message;

		}

	}	//	function _writeDebug()



	/**

	 * Clear the calculation engine debug log

	 */

	public function clearLog() {

		$this->_debugLog = array();

	}	//	function flushLogger()



	/**

	 * Return the calculation engine debug log

	 *

	 * @return  string[]

	 */

	public function getLog() {

		return $this->_debugLog;

	}	//	function flushLogger()



}	//	class PHPExcel_CalcEngine_Logger



