<?php
/**
 * Copyright 2009, 2010 AEGEE-Europe
 *
 * This file is part of AEGEE-Europe Online Membership System.
 *
 * AEGEE-Europe Online Membership System is free software: you can
 * redistribute it and/or modify it under the terms of the GNU General
 * Public License as published by the Free Software Foundation, either
 * version 3 of the License, or (at your option) any later version.
 *
 * AEGEE-Europe Online Membership System 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with AEGEE-Europe Online Membership System.  If not, see
 * <http://www.gnu.org/licenses/>.
 */

/**
 * Pager object to display a list
 */

require_once(FILESYSTEMROOTPATH."include/list/CounterColumn.php");
require_once(FILESYSTEMROOTPATH."include/list/DateColumn.php");
require_once(FILESYSTEMROOTPATH."include/list/TextColumn.php");

class ListPager {
	private $name;
	private $extraParms;
	private $columns;
	private $pageSize;
	private $defaultSort;
	private $sortTranslator;
	private $sort;
	private $sortOrder;
	private $page;

	/**
	 * Constructor
	 *
	 * @param string name of the shown data (free string, must be unique)
	 * @param string extraParms parameters to be added to links in http encoding
	 * @throws InvalidArgumentException in case arguments are invalid
	 */
	public function __construct($name, $extraParms="") {
		$this->name = $name;
		$this->extraParms = $extraParms;
		
		//if extraParms empty but page was called with extra params
		if ($extraParms=="" && $_SERVER['QUERY_STRING']){
			$extraParms = $_SERVER['QUERY_STRING'];
			//remove sort and asc/desc from query string
			$extraParms = preg_replace("/sort=([a-zA-Z_]+)(&|$)/", "", $extraParms); 
			$extraParms = preg_replace("/page=([0-9]+)(&|$)/", "", $extraParms);
			$extraParms = str_replace(array("asc","desc","asc&","desc&"),"",$extraParms);
			$this->extraParms = $extraParms;
		}
		
		if( strlen($this->extraParms)>0 && substr($this->extraParms, 0, 1)!="&" ) {
			$this->extraParms = "&amp;" . $this->extraParms;
		}
		$this->columns = array();
		if( defined("MAXLISTLENGTH") ) {
			$this->pageSize = MAXLISTLENGTH;
		}else {
			$this->pageSize = 25;
		}
		$this->defaultSort = "";
		$this->sortTranslator = array();
		$this->sort = "";
		$this->sortOrder = "asc";
		$this->page = 1;
	}

	/**
	 * Display the list
	 *
	 * @param array data to be shown (2-dimensional)
	 */
	public function display($data) {
		if( !isset($data) || !is_array($data) ) {
			throw new InvalidArgumentException(_("No data array given"));
		}
		// Sort order in session
		if( isset($_REQUEST['sort']) AND array_key_exists($_REQUEST['sort'], $this->columns) ) {
			$this->sort = $_REQUEST['sort'];
			$_SESSION['ListPager'][$this->name]['sort'] = $_REQUEST['sort'];
		}elseif( isset($_SESSION['ListPager'][$this->name]['sort']) ) {
			$this->sort = $_SESSION['ListPager'][$this->name]['sort'];
		}elseif( array_key_exists($this->defaultSort, $this->columns) || $this->defaultSort=="" ) {
			$this->sort = $this->defaultSort;
		}else {
			throw new InvalidArgumentException(_("The default sort should be a column."));
		}

		if( isset($_REQUEST['asc']) ) {
			$this->sortOrder = "asc";
			$_SESSION['ListPager'][$this->name]['sortOrder'] = "asc";
		}elseif( isset($_REQUEST['desc']) ) {
			$this->sortOrder = "desc";
			$_SESSION['ListPager'][$this->name]['sortOrder'] = "desc";
		}elseif( isset($_SESSION['ListPager'][$this->name]['sortOrder']) ) {
			$this->sortOrder = $_SESSION['ListPager'][$this->name]['sortOrder'];
		}
		// Page in session
		if( isset($_REQUEST['page']) AND $this->isPageWithinLimits($_REQUEST['page'], $data) ) {
			$this->page = $_REQUEST['page'];
			$_SESSION['ListPager'][$this->name]['page'] = $_REQUEST['page'];
		}elseif( isset($_SESSION['ListPager'][$this->name]['page']) AND $this->isPageWithinLimits($_SESSION['ListPager'][$this->name]['page'], $data) ) {
			$this->page = $_SESSION['ListPager'][$this->name]['page'];
		}else {
			$this->page = 1;
		}
		// If columns not set, create
		if( count($this->columns)<1 ) {
			$columns = array_keys(current($data));
			$this->columns = array();
			for( $i=0; $i<count($columns); $i++ ) {
				$this->columns[] = new TextColumn($columns[$i], $columns[$i]);
			}
		}
		if( $this->sort!="" && array_key_exists($this->sort, $this->columns) ) {
			// Sort data
			if( $this->sortOrder=="desc" ) {
				uasort($data, array($this, "sortDataDesc"));
			}else {
				uasort($data, array($this, "sortDataAsc"));
			}
		}
		// Pager
		if( count($data)<=$this->pageSize ) {
			$start = 0;
			$end = count($data);
			$pager = "";
		}else {
			$start = ($this->page-1) * $this->pageSize;
			$end = min(count($data), $start+$this->pageSize);
			if( $this->page>1 ) {
				$pager = "<a href=\"?page=1".$this->extraParms."\">&laquo;</a> <a href=\"?page=".($this->page-1).$this->extraParms."\">&lt;</a> ";
			}else {
				$pager = "&laquo; &lt; ";
			}
			for( $c=1; $c<=ceil(count($data)/$this->pageSize); $c++ ) {
				if( $c==$this->page ) {
					$pager .= "<b>".$c."</b> ";
				}else {
					$pager .= "<a href=\"?page=".$c.$this->extraParms."\">".$c."</a> ";
				}
			}
			if( $this->page<ceil(count($data)/$this->pageSize) ) {
				$pager .= "<a href=\"?page=".($this->page+1).$this->extraParms."\">&gt;</a> <a href=\"?page=".ceil(count($data)/$this->pageSize).$this->extraParms."\">&raquo;</a>";
			}else {
				$pager .= "&gt; &raquo;";
			}
			$pager .= " (showing ".($start+1)." - ".$end." of ".count($data).")";
		}
		// Build table
		$rowkeys = array_keys($data);
		$res = "<div class=\"pager\">".$pager."</div>";
		$res .= "<p><table>";
		// Table Title
		$res .= "<thead><tr><th colspan=\"".count($this->columns)."\">".$this->name."</th></tr>";
		// Headers
		$res .= "<tr>";
		foreach($this->columns as $columnObject) {
			$res .= "<th>";
			if( $columnObject->isSortable() ) {
				$res .= "<a href=\"?sort=".$columnObject->getName()."&amp;".(($columnObject->getName()==$this->sort && $this->sortOrder=="asc")?"desc":"asc").$this->extraParms."\">";
			}
			$res .= $columnObject->getHeader();
			if( $columnObject->isSortable() ) {
				$res .= "</a>";
			}
			$res .= "</th>";
		}
		$res .= "</tr></thead>";
		// Body
		$res .= "<tbody>";
		for( $r=$start; $r<$end; $r++ ) {
			$res .= "<tr class=\"".(($r%2)==0?"even":"odd")."\">";
			foreach($this->columns as $columnObject) {
				$res .= "<td>".$columnObject->getCellValue($r, $data[ $rowkeys[$r] ])."</td>";
			}
			$res .= "</tr>";
		}
		$res .= "</tbody></table>";
		$res .= "<p><div class=\"pager\">".$pager."</div>";
		return $res;
	}

	/**
	 * Get the name of the data
	 *
	 * @return string name of the data
	 */
	public function getName() {
		return $this->name;
	}

	/**
	 * Add a column
	 *
	 * @param IColumn column to be shown.
	 */
	public function addColumn(IColumn $column) {
		$this->columns[$column->getName()] = $column;
	}

	/**
	 * Get the maximum page size
	 *
	 * @return maximum page size
	 */
	public function getPageSize() {
		return $this->pageSize;
	}

	/**
	 * Set the maximum page size
	 *
	 * @param int pagesize number of items to show per page
	 * @throws InvalidArgumentException if size is not numerical and positive
	 */
	public function setPageSize($pageSize) {
		if( is_numeric($pageSize) AND $pageSize>0 ) {
			$this->pageSize = $pageSize;
		}else {
			throw new InvalidArgumentException(_("The page size should be numerical and positive."));
		}
	}

	public function getDefaultSort() {
		return $this->defaultSort;
	}

	public function setDefaultSort($defaultSort) {
		$this->defaultSort = $defaultSort;
	}

	public function getSortTranslator() {
		return $this->sortTranslator;
	}

	public function setSortTranslator($sortTranslator) {
		if( is_array($sortTranslator) ) {
			$this->sortTranslator = $sortTranslator;
		}else {
			throw new InvalidArgumentException(_("The sort translator should be an array."));
		}
	}

	private function sortDataAsc($a, $b) {
		if( array_key_exists($this->sort, $this->sortTranslator) ) {
			$sort = explode(",", $this->sortTranslator[$this->sort]);
			for( $i=0; $i<count($sort); $i++ ) {
				if( $a[ $sort[$i] ]<$b[ $sort[$i] ] ) {
					return -1;
				}elseif( $a[ $sort[$i] ]>$b[ $sort[$i] ] ) {
					return 1;
				}
			}
			return 0;
		}else {
			if( $a[$this->sort]==$b[$this->sort] ) {
				return 0;
			}else {
				return ($a[$this->sort]<$b[$this->sort] ? -1 : 1);
			}
		}
	}

	private function sortDataDesc($a, $b) {
		return $this->sortDataAsc($b, $a);
	}

	private function isPageWithinLimits($page, $data) {
		return $page>0 AND $page<=ceil(count($data)/$this->pageSize);
	}
}
?>