<?php
/**
 *
 * @package XCube
 * @version $Id: XCube_PageNavigator.class.php,v 1.1.2.8 2006/12/26 14:30:54 nobunobu Exp $
 * @copyright Copyright 2005, 2006 XOOPS Cube Project <http://xoopscube.org/>
 * @license http://xoopscube.sourceforge.net/bsd_licenses.txt Modified BSD license
 *
 */

define('XCUBE_PAGENAVI_START', 1);
define('XCUBE_PAGENAVI_PERPAGE', 2);

define('XCUBE_PAGENAVI_SORT', 1);
define('XCUBE_PAGENAVI_PAGE', 4);

define('XCUBE_PAGENAVI_DEFAULT_PERPAGE', 20);

/**
 * This is a utility class which acquires page navigation informations
 * --- sort, offset and limit --- semiautomatically. And, the base modules may
 * offer place holders which is able to connect with interfaces of this class.
 */
class XCube_PageNavigator
{
	/**
	 * Array for extra informations.
	 * @var Array
	 */
	var $mAttributes = array();
	
	/**
	 * Offset.
	 * @var int
	 */
	var $mStart = 0;
	
	/**
	 * The max number of items which this navigator handles.
	 * @var int
	 */
	var $mTotalItems = 0;

	/**
	 * Per page.
	 * @var int
	 */
	var $mPerpage = XCUBE_PAGENAVI_DEFAULT_PERPAGE;
	
	/**
	 * Flag indicating whether this class receives the perpage value specified
	 * by the request.
	 * @var bool
	 */
	var $mPerpageFreeze = false;
	
	/**
	 * Array for sort.
	 * @var Array
	 */
	var $mSort = array();
	
	/**
	 * The base url for this navigator.
	 * @var string
	 */
	var $mUrl = "";

	/**
	 * A prefix for variable names fetched by this navigator. If two independent
	 * navigators are used, this property is must.
	 */	
	var $mPrefix = null;

	/**
	 * Array of string for re-building the query strings.
	 */
	var $mExtra = array();
	
	/**
	 * Options indicating what this navigator fetches automatically.
	 */
	var $mFlags = 0;

	/**
	 * @XCube_Delegate
	 */	
	var $mFetch = null;
	
	/**
	 * The value indicating whether the mTotal property already has been
	 * specified.
	 * @var bool
	 */
	var $_mIsSpecifedTotalItems = false;
	
	/**
	 * This delegate is used in only case which mTotal isn't set yet.
	 * 
	 * void getTotal(int &total, const XCube_Navigator);
	 * 
	 * @var XCube_Delegate
	 */
	var $mGetTotalItems = null;
	
	
	/**
	 * Constructor.
	 * @param string $url
	 * @param int $total
	 * @param int flag
	 */
	function XCube_PageNavigator($url, $flags = XCUBE_PAGENAVI_START)
	{
		$this->mUrl = $url;
		$this->mFlags = $flags;
		
		$this->mFetch =& new XCube_Delegate();
		$this->mFetch->add(array(&$this, 'fetchNaviControl'));
		
		$this->mGetTotalItems =& new XCube_Delegate();
	}
	
	/**
	 * Gets values which this navigator handles, from the request. And, sets
	 * values to this object's properties.
	 */
	function fetch()
	{
		$this->mFetch->call(new XCube_Ref($this));
	}
	
	function fetchNaviControl()
	{	
		$root =& XCube_Root::getSingleton();
		
		$startKey = $this->getStartKey();
		$perpageKey = $this->getPerpageKey();
		
		if ($this->mFlags & XCUBE_PAGENAVI_START) {
			$t_start = $root->mContext->mRequest->getRequest($this->getStartKey());
			if ($t_start != null && intval($t_start) >= 0) {
				$this->mStart = intval($t_start);
			}
		}

		if ($this->mFlags & XCUBE_PAGENAVI_PERPAGE && !$this->mPerpageFreeze) {
			$t_perpage = $root->mContext->mRequest->getRequest($this->getPerpageKey());
			if ($t_perpage != null && intval($t_perpage) > 0) {
				$this->mPerpage = intval($t_perpage);
			}
		}
	}

	function addExtra($key, $value)
	{
		$this->mExtra[$key] = $value;
	}
	
	function removeExtra($key)
	{
		if ($this->mExtra[$key]) {
			unset($this->mExtra[$key]);
		}
	}
	
	function getRenderBaseUrl($mask = null)
	{
		if ($mask == null) {
			$mask = array();
		}
		if (!is_array($mask)) {
			$mask = array($mask);
		}
		
		if(count($this->mExtra) > 0) {
			$tarr=array();
			
			foreach($this->mExtra as $key=>$value) {
				if (is_array($mask) && !in_array($key, $mask)) {
					$tarr[]=$key."=".urlencode($value);
				}
			}
			
			if (count($tarr)==0) {
				return $this->mUrl;
			}
			
			if(strpos($this->mUrl,"?")!==false) {
				return $this->mUrl."&amp;".implode("&amp;",$tarr);
			}
			else {
				return $this->mUrl."?".implode("&amp;",$tarr);
			}
		}
		
		return $this->mUrl;
	}
	
	/**
	 * Return url string for navigation. The return value is lose start value.
	 * The user need to add start value. For example, It is "$navi->getRenderUrl().'20'".
	 * This method name is bad. I must rename this.
	 * @return string
	 */
	function getRenderUrl($mask = null)
	{
		if ($mask != null && !is_array($mask)) {
			$mask = array($mask);
		}
		
		$demiliter = "?";
		$url = $this->getRenderBaseUrl($mask);
		
		if(strpos($url,"?")!==false) {
			$demiliter = "&amp;";
		}
		
		return $url . $demiliter . $this->getStartKey() . "=";
	}
	
	function renderUrlForSort()
	{
		if(count($this->mExtra) > 0) {
			$tarr=array();
			
			foreach($this->mExtra as $key=>$value) {
				$tarr[]=$key."=".urlencode($value);
			}
			
			$tarr[] = $this->getPerpageKey() . "=" . $this->mPerpage;
			
			if(strpos($this->mUrl,"?")!==false) {
				return $this->mUrl."&amp;".implode("&amp;",$tarr);
			}
			else {
				return $this->mUrl."?".implode("&amp;",$tarr);
			}
		}
		
		return $this->mUrl;
	}
	
	function renderUrlForPage($page = null)
	{
		$tarr=array();
			
		foreach($this->mExtra as $key=>$value) {
			$tarr[]=$key."=".urlencode($value);
		}
			
		foreach($this->mSort as $key=>$value) {
			$tarr[]=$key."=".urlencode($value);
		}
			
		$tarr[] = $this->getPerpageKey() . "=" . $this->getPerpage();
		
		if ($page !== null) {
			$tarr[] = $this->getStartKey() . '=' . intval($page);
		}
			
		if(strpos($this->mUrl,"?")!==false) {
			return $this->mUrl."&amp;".implode("&amp;",$tarr);
		}
		else {
			return $this->mUrl."?".implode("&amp;",$tarr);
		}
		
		return $this->mUrl;
	}
	
	/**
	 * Return url string for sort. The return value is complete style.
	 * @deprecated
	 */
	function renderSortUrl($mask = null)
	{
		return $this->renderUrlForSort();
	}

	function setStart($start)
	{
		$this->mStart = intval($start);
	}
	
	function getStart()
	{
		return $this->mStart;
	}
	
	function setTotalItems($total)
	{
		$this->mTotal = intval($total);
		$this->_mIsSpecifiedTotal = true;
	}
	
	function getTotalItems()
	{
		if ($this->_mIsSpecifedTotalItems == false) {
			$this->mGetTotalItems->call(new XCube_Ref($this->mTotal));
			$this->_mIsSpecifedTotalItems = true;
		}
		
		return $this->mTotal;
	}
	
	function getTotalPages()
	{
		if ($this->getPerpage() > 0) {
			return ceil($this->getTotalItems() / $this->getPerpage());
		}
		
		return 0;
	}

	function setPerpage($perpage)
	{
		$this->mPerpage = intval($perpage);
	}
	
	function freezePerpage()
	{
		$this->mPerpageFreeze = true;
	}
	
	function getPerpage()
	{
		return $this->mPerpage;
	}

	function setPrefix($prefix)
	{
		$this->mPrefix = $prefix;
	}
	
	function getPrefix()
	{
		return $this->mPrefix;
	}

	function getStartKey()
	{
		return $this->mPrefix . "start";
	}

	function getPerpageKey()
	{
		return $this->mPrefix . "perpage";
	}
	
	function getCurrentPage()
	{
		return intval(floor(($this->getStart() + $this->getPerpage()) / $this->getPerpage()));
	}
	
	function hasPrivPage()
	{
		return ($this->getStart() - $this->getPerpage()) >= 0;
	}

	function getPrivStart()
	{
		$prev = $this->getStart() - $this->getPerpage();
		
		return ($prev > 0) ? $prev : 0;
	}

	function hasNextPage()
	{
		return $this->getTotalItems() > ($this->getStart() + $this->getPerpage());
	}

	function getNextStart()
	{
		$next = $this->getStart() + $this->getPerpage();
		
		return ($this->getTotalItems() > $next) ? $next : 0;
	}
}

?>