<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_View
 * @subpackage Helper
 * @copyright  Copyright (c) 2005-2011 Zend Technologies USA Inc. (http://www.zend.com)
 * @version    $Id: Cycle.php 23953 2011-05-03 05:47:39Z ralph $
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */

/**
 * Helper for alternating between set of values
 *
 * @package    Zend_View
 * @subpackage Helper
 * @copyright  Copyright (c) 2005-2011 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class Zend_View_Helper_Cycle implements Iterator
{

    /**
     * Default name
     * @var string
     */
    const DEFAULT_NAME = 'default';

    /**
     * Pointers
     *
     * @var array
     */
    protected $_pointers = array(self::DEFAULT_NAME =>-1) ;

    /**
     * Array of values
     *
     * @var array
     */
    protected $_data = array(self::DEFAULT_NAME=>array());

    /**
     * Actual name of cycle
     *
     * @var string
     */
    protected $_name = self::DEFAULT_NAME;

    /**
     * Add elements to alternate
     *
     * @param array $data
     * @param string $name
     * @return Zend_View_Helper_Cycle
     */
    public function cycle(array $data = array(), $name = self::DEFAULT_NAME)
    {
        if(!empty($data))
           $this->_data[$name] = $data;

        $this->setName($name);
        return $this;
    }

    /**
     * Add elements to alternate
     *
     * @param array $data
     * @param string $name
     * @return Zend_View_Helper_Cycle
     */
    public function assign(Array $data , $name = self::DEFAULT_NAME)
    {
        $this->setName($name);
        $this->_data[$name] = $data;
        $this->rewind();
        return $this;
    }

    /**
     * Sets actual name of cycle
     *
     * @param string $name
     * @return Zend_View_Helper_Cycle
     */
    public function setName($name = self::DEFAULT_NAME)
    {
       $this->_name = $name;

       if(!isset($this->_data[$this->_name]))
         $this->_data[$this->_name] = array();

       if(!isset($this->_pointers[$this->_name]))
         $this->rewind();

       return $this;
    }

    /**
     * Gets actual name of cycle
     *
     * @return string
     */
    public function getName()
    {
        return $this->_name;
    }


    /**
     * Return all elements
     *
     * @return array
     */
    public function getAll()
    {
        return $this->_data[$this->_name];
    }

    /**
     * Turn helper into string
     *
     * @return string
     */
    public function toString()
    {
        return (string) $this->_data[$this->_name][$this->key()];
    }

    /**
     * Cast to string
     *
     * @return string
     */
    public function __toString()
    {
        return $this->toString();
    }

    /**
     * Move to next value
     *
     * @return Zend_View_Helper_Cycle
     */
    public function next()
    {
        $count = count($this->_data[$this->_name]);
        if ($this->_pointers[$this->_name] == ($count - 1))
            $this->_pointers[$this->_name] = 0;
        else
            $this->_pointers[$this->_name] = ++$this->_pointers[$this->_name];
        return $this;
    }

    /**
     * Move to previous value
     *
     * @return Zend_View_Helper_Cycle
     */
    public function prev()
    {
        $count = count($this->_data[$this->_name]);
        if ($this->_pointers[$this->_name] <= 0)
            $this->_pointers[$this->_name] = $count - 1;
        else
            $this->_pointers[$this->_name] = --$this->_pointers[$this->_name];
        return $this;
    }

    /**
     * Return iteration number
     *
     * @return int
     */
    public function key()
    {
        if ($this->_pointers[$this->_name] < 0)
            return 0;
        else
            return $this->_pointers[$this->_name];
    }

    /**
     * Rewind pointer
     *
     * @return Zend_View_Helper_Cycle
     */
    public function rewind()
    {
        $this->_pointers[$this->_name] = -1;
        return $this;
    }

    /**
     * Check if element is valid
     *
     * @return bool
     */
    public function valid()
    {
        return isset($this->_data[$this->_name][$this->key()]);
    }

    /**
     * Return  current element
     *
     * @return mixed
     */
    public function current()
    {
        return $this->_data[$this->_name][$this->key()];
    }
}
