<?php
/**
 * PHPPowerPoint
 *
 * Copyright (c) 2009 - 2010 PHPPowerPoint
 *
 * 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   PHPPowerPoint
 * @package    PHPPowerPoint
 * @copyright  Copyright (c) 2009 - 2010 PHPPowerPoint (http://www.codeplex.com/PHPPowerPoint)
 * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt	LGPL
 * @version    0.1.0, 2009-04-27
 */


/** PHPPowerPoint_IComparable */
require_once 'PHPPowerPoint/IComparable.php';


/**
 * PHPPowerPoint_HashTable
 *
 * @category   PHPPowerPoint
 * @package    PHPPowerPoint
 * @copyright  Copyright (c) 2009 - 2010 PHPPowerPoint (http://www.codeplex.com/PHPPowerPoint)
 */
class PHPPowerPoint_HashTable
{
    /**
     * HashTable elements
     *
     * @var array
     */
    public $_items = array();
    
    /**
     * HashTable key map
     *
     * @var array
     */
    public $_keyMap = array();
	
    /**
     * Create a new PHPPowerPoint_HashTable
     *
     * @param 	PHPPowerPoint_IComparable[] $pSource	Optional source array to create HashTable from
     * @throws 	Exception
     */
    public function __construct($pSource = null)
    {
    	if (!is_null($pSource)) {
	        // Create HashTable
	        $this->addFromSource($pSource);
    	}
    }
    
    /**
     * Add HashTable items from source
     *
     * @param 	PHPPowerPoint_IComparable[] $pSource	Source array to create HashTable from
     * @throws 	Exception
     */
    public function addFromSource($pSource = null) {
    	// Check if an array was passed
        if ($pSource == null) {
            return;
        } else if (!is_array($pSource)) {
            throw new Exception('Invalid array parameter passed.');
        }
        
        foreach ($pSource as $item) {
            $this->add($item);
        }
    }

    /**
     * Add HashTable item
     *
     * @param 	PHPPowerPoint_IComparable $pSource	Item to add
     * @throws 	Exception
     */
    public function add(PHPPowerPoint_IComparable $pSource = null) {
	    // Determine hashcode
    	$hashCode 	= null;
	    $hashIndex = $pSource->getHashIndex();
	    if ( is_null ( $hashIndex ) ) {
	        $hashCode = $pSource->getHashCode();
	    } else if ( isset ( $this->_keyMap[$hashIndex] ) ) {
	        $hashCode = $this->_keyMap[$hashIndex];
	    } else {
	        $hashCode = $pSource->getHashCode();
	    }
	        
	    // Add value      
   		if (!isset($this->_items[ $hashCode ])) {
            $this->_items[ $hashCode ] = $pSource;
            $index = count($this->_items) - 1;
            $this->_keyMap[ $index  ] = $hashCode;
            $pSource->setHashIndex( $index );
   		} else {
            $pSource->setHashIndex( $this->_items[ $hashCode ]->getHashIndex() );
		}
    }
    
    /**
     * Remove HashTable item
     *
     * @param 	PHPPowerPoint_IComparable $pSource	Item to remove
     * @throws 	Exception
     */
    public function remove(PHPPowerPoint_IComparable $pSource = null) {
    	if (isset($this->_items[  $pSource->getHashCode()  ])) {
	   		unset($this->_items[  $pSource->getHashCode()  ]);
	    		
	   		$deleteKey = -1;
	   		foreach ($this->_keyMap as $key => $value) {    			
	   			if ($deleteKey >= 0) {
	   				$this->_keyMap[$key - 1] = $value;
	   			}
	    			
	   			if ($value == $pSource->getHashCode()) {
	   				$deleteKey = $key;
	   			}
	   		}
	   		unset($this->_keyMap[ count($this->_keyMap) - 1 ]);   
    	}         
    }
    
    /**
     * Clear HashTable
     *
     */
    public function clear() {
    	$this->_items = array();
    	$this->_keyMap = array();
    }
    
    /**
     * Count
     *
     * @return int
     */
    public function count() {
    	return count($this->_items);
    }
    
    /**
     * Get index for hash code
     *
     * @param 	string 	$pHashCode
     * @return 	int 	Index
     */
    public function getIndexForHashCode($pHashCode = '') {
    	return array_search($pHashCode, $this->_keyMap);
    }
    
    /**
     * Get by index
     *
     * @param	int	$pIndex
     * @return 	PHPPowerPoint_IComparable
     *
     */
    public function getByIndex($pIndex = 0) {
    	if (isset($this->_keyMap[$pIndex])) {
    		return $this->getByHashCode( $this->_keyMap[$pIndex] );
    	}
    	
    	return null;
    }
    
    /**
     * Get by hashcode
     *
     * @param	string	$pHashCode
     * @return 	PHPPowerPoint_IComparable
     *
     */
    public function getByHashCode($pHashCode = '') {
    	if (isset($this->_items[$pHashCode])) {
    		return $this->_items[$pHashCode];
    	}
    	
    	return null;
    }
    
    /**
     * HashTable to array
     *
     * @return PHPPowerPoint_IComparable[]
     */
    public function toArray() {
    	return $this->_items;
    }
        
	/**
	 * Implement PHP __clone to create a deep clone, not just a shallow copy.
	 */
	public function __clone() {
		$vars = get_object_vars($this);
		foreach ($vars as $key => $value) {
			if (is_object($value)) {
				$this->$key = clone $value;
			}
		}
	}
}