<?php
/**
* Paging class to iterate through limited recordsets
* @author Nick Korbel <lqqkout13@users.sourceforge.net>
* @version 02-02-05
* @package Pager
*
* Copyright (C) 2003 - 2005 phpScheduleIt
* License: GPL, see LICENSE
* /
/**
* To actually print out page links, call printPages() function
*
* In order for this object to work correctly, total records
*  must be set in either the constructor or by calling
*  setTotRecords()
*
* + Warning - The printPages() function cannot be called
* 			from within a form
*
* === EXAMPLE OF HOW TO USE PAGER ===
* // Initialize new Pager object with default values
* $pager = new Pager();
*
* // Get total # of pages
* $query = "SELECT COUNT(*) as num FROM table";
* $result = $db->query($query);    
* $rs = $result->fetchRow();
* $num = $rs['num'];              // # of records
*
* $pager->setTotRecords($num);
* $recordset_offset = $pager->getOffset();
* $limit = $pager->getLimit();
*
* // Execute Query (using $offset and $limit values) //
*
* $pager->printPages();
* ==========================================
*
*/

// Should we use the Link class?
$use_link = true;

if ($use_link) {
	//include_once('Link.class.php');
	$link = new Link();
}

class Pager {
	// Application set variables
	var $cur_page;
	var $query_string;
	var $tot_pages;
	var $page_var;
	var $limit_var;
	
	// Application variables with user modify option
	var $limit;
	var $tot_records;
	var $print_limit_select = true;
	
	// User modifiable variables
	var $prev_link = '&laquo;';
	var $next_link = '&raquo;';
	var $limits = array(10, 25, 50, 100);
	var $view_pages = 3;
	var $table_width = '100%';
	var $table_align = 'center';
	var $link_class;
	var $tb_class;
	var $tb_style;
	var $text_class;
	var $text_style;
	
		
	/**
	* Pager Constructor
	* Sets up Pager variables and initializes values
	*
	* - All parameters are optional and have default values of:
	*    $tot_records = 0
	*    $limit = 25
	*    $page_var = "page"
	*    $limit_var = "limit"
	*
	* @param int $tot_records optional total number of records
	* @param int $limit optional limit of recordset
	* @param string $page_var optional name of var to use in querystring for page value
	* @param string $limit_var optional name of var to use in querystring for limit value
	*/
	function Pager($tot_records=0, $limit=25, $page_var='page', $limit_var='limit') {
		$this->tot_records = $tot_records;
		$this->limit = $limit;
		$this->page_var = $page_var;
		$this->limit_var = $limit_var;
		
		// Call all system setter functions
		$this->initCurPage();
		$this->initLimit();
		$this->initTotPages();
		$this->initQueryString();
	}
	
	
	/**
	* Print out the pages as links
	* Prints out a table of all the pages as links
	*  and a jump menu to change the number of records
	*  per page
	*
	* setCurPage() and setTotPages() must be called
	*  before this function can be called
	*
	* @param none
	* @see printPrev()
	* @see printLink()
	* @see printPage()
	* @see printNext()
	* @see printTotal()
	* @see startTable()
	* @see startPagesCell()
	* @see endPagesCell()
	* @see printLimitCell()
	* @see endTable()
	*/
	function printPages() {
		$p = $this->view_pages;			// How many pages to view
		$cur_page = $this->cur_page;	// Current page
		$tot_pages = $this->tot_pages;	// Total pages
		
		// Open up the HTML table
		$this->startTable();
		// Open up cell for page links
		$this->startPagesCell();
		
		// Page to start printing bulk of links
		$start = ($cur_page > $p) ? $cur_page - $p : 1;
		// Page to end printing bulk of links
		$end = ($cur_page + $p) < $tot_pages ? $cur_page + $p : $tot_pages;
		
		// Print 'prev' link
		$this->printPrev();
		
		// Print link to first page, if not already there
		if ($start != 1) {
			$this->printPage(1);
		}
		
		// Print '...' if necessary (with link to center page)
		if ($cur_page > $p+2) {
			$this->printLink(ceil( ($start+1)/2 ), '...');
		}
		
		// Print links to pages before current page (up to first page)
		// Print current page
		// Print links to pages after current page (up to last page)		
		for ($pg = $start; $pg <= $end; $pg++) {
			$this->printPage($pg);
		}
				
		// Print '...' if necessary (with link to center page)
		if ( $cur_page < ($tot_pages - ($p+1)) ) {
			$this->printLink(ceil( ($tot_pages+$end)/2 ), '...' );
		}
		
		// Print link to last page, if not already there
		if ($end != $tot_pages) {
			$this->printPage($tot_pages);
		}
		
		// Print 'next' link
		$this->printNext();
		
		// Print total records
		$this->printTotal();
		
		// Close page links cell
		$this->endPagesCell();
		// Print out cell with limit jump menu
		if ($this->print_limit_select) { $this->printLimitCell(); }
		// Close table
		$this->endTable();
	}
	
	//-----------------------------------------
	// Application setter functions
	//-----------------------------------------
	/**
	* Sets current page variable
	* @param none
	*/
	function initCurPage() {
		$this->cur_page = isset($_GET[$this->page_var]) ? intval($_GET[$this->page_var]) : 1;
	}
	
	/**
	* Sets the limit variable if it is passed from querystring
	* @param none
	*/
	function initLimit() {
		if (isset($_GET[$this->limit_var]))
			$this->limit = intval($_GET[$this->limit_var]);
		if (isset($_POST[$this->limit_var]))
			$this->limit = intval($_POST[$this->limit_var]);
	}
	
	/**
	* Pull page information from query string and set $query_string
	*
	* setLimit() must be called before this function for it to work correctly
	* @param none
	*/
	function initQueryString() {
	    if (isset($_SERVER['QUERY_STRING'])) {
			// Remove page from query string and convert all "&" to "&amp;"
			$this->query_string = str_replace('&', '&amp;', preg_replace("/(&|&amp;)?$this->page_var=\d*/",'',$_SERVER['QUERY_STRING']));
			
			// Insert limit into querystring, if it's not there
			if ( !strstr($this->query_string, "$this->limit_var=") )
				$this->query_string .= "&amp;$this->limit_var=" . $this->limit;
		}
		else {
			$this->query_string = '';
		}

	}
	
	/**
	* Sets the tot_pages variable
	*
	* tot_records must be set and setLimit() must be called before
	*  this function can be called
	*
	* @param none
	*/
	function initTotPages() {
		$this->tot_pages = ceil($this->tot_records/$this->limit);
	}
	//===========================================
	
	//-------------------------------------------
	// Output functions
	//-------------------------------------------	
	/**
	* Print out link to a page
	* @param int $p page number to print
	*/
	function printPage($p) {
		if ($p == $this->cur_page) {
			echo " <b>[$p]</b> ";
		}
		else {
			$this->printLink($p, $p);
		}
	}
	
	/**
	* Print 'prev' link, if necessary
	* @param none
	*/
	function printPrev() {
		$cur_page = $this->cur_page;
		if ($cur_page > 1)
			$this->printLink($cur_page-1, $this->prev_link);
	}
	
	/**
	* Print 'next' link, if necessary
	* @param none
	*/
	function printNext() {
		$cur_page = $this->cur_page;
		if ($cur_page < $this->tot_pages && $this->tot_records > 0)
			$this->printLink($cur_page+1, $this->next_link);
	}
	
	/**
	* Print out link to a certain page
	* @param int $page page to link to
	* @param string $text link text
	*/
	function printLink($page, $text) {
		global $link;
		global $use_link;
		
		if ($use_link) {
			$link->doLink(
				$_SERVER['PHP_SELF'] . "?$this->page_var=$page&amp;" . $this->query_string . '"',
				$text,
				$this->link_class,
				'',
				'Page ' . $page
				);
		}
		else {
			echo ' <a href="' . $_SERVER['PHP_SELF'] . "?$this->page_var=$page&amp;" . $this->query_string . '"'
				. ' class="$this->class"'
				. '>'
				. $text . '</a> ';
		}
	}
	
	/**
	* Prints out opening table tag
	* @param none
	*/
	function startTable() {
		echo "<table align=\"$this->table_align\" border=\"0\" cellpadding=\"0\" cellspacing=\"0\" width=\"$this->table_width\">\n"
			. "<tr class=\"$this->text_class\" style=\"$this->text_style\">\n";	
	}
	
	/**
	* Begins cell containing page links
	* @param none
	*/
	function startPagesCell() {
		echo '<td>' . translate('Page') . ' ';
	}
	
	/**
	* Closes cell containing page links
	* @param none
	*/
	function endPagesCell() {
		echo '</td>';
	} 
	
	/**
	* Prints out cell containing limit jump menu
	* @param none
	*/
	function printLimitCell() {
		$limits = $this->limits;
		echo "<td align=\"right\">\n"
			. "<form name=\"limit_jump\" id=\"limit_jump\" method=\"post\" action=\"" . $_SERVER['PHP_SELF'] . "?" . preg_replace("/(&|&amp;)?$this->limit_var=\d*/", "", $this->query_string) . "\" style=\"margin: 0px;\">\n"
			. translate('Per page') . " <select name=\"$this->limit_var\" onchange=\"document.limit_jump.submit();\" class=\"$this->tb_class\" style=\"$this->tb_style\">\n";
		for ($i = 0; $i < count($limits); $i++) {
			echo '<option value="' . $limits[$i] . '"';
			if ($limits[$i] == $this->limit)
				echo ' selected="selected"';
			echo '>' . $limits[$i] . "</option>\n";
		}
		echo "</select>\n"
			. "</form>\n"
			. "</td>\n";
	}
	
	/**
	* Prints out the closing row and table HTML tags
	* @param none
	*/
	function endTable() {
		echo "</tr>\n</table>\n";
	}
	
	/**
	* Prints out total number of records returned
	* @param none
	*/
	function printTotal() {
		echo '(' . $this->tot_records . ')';
	}
	//============================================

	//--------------------------------------------
	// User-Modified Setter Functions
	//--------------------------------------------	
	/**
	* Sets the total records for this recordset
	* 
	* - Default setting is 0 (in constructor)
	*
	* @param int $tot total number of records
	*/
	function setTotRecords($tot) {
		$this->tot_records = intval($tot);
		// Call initTotPages again to reset paging
		$this->initTotPages();
	}
	
	/**
	* Sets the default recordset limit
	* Note: A limit value set in the querystring
	*  or in a post value will override this
	*
	* - Default setting is 25 (in constructor)
	*
	* @param int $limit new limit value
	*/
	function setLimit($limit) {
		$this->limit = intval($limit);
		// Call initLimit() to reinitialzie limit
		$this->initLimit();
	}
	
	/**
	* Sets the text for 'prev' link
	*
	* - Default setting is "&laquo;"
	*
	* @param string $text link text
	*/
	function setPrevLink($text) {
		$this->prev_link = trim($text);
	}
	
	/**
	* Sets the text for 'next' link
	*
	* - Default setting is "&raquo;"
	*
	* @param string $text link text
	*/
	function setNextLink($text) {
		$this->next_link = trim($text);
	}
		
	/**
	* Sets the value of view_pages
	* How many pages to print on either side of
	* the currently viewed page number
	*
	* - Default setting is 3
	*
	* @param int $view_page how many pages to view
	*/
	function setViewPages($view_page) {
		$this->view_pages = intval($view_page);
	}
	
	/**
	* Sets the array of limits
	* Pass in an array of ints to use
	* for the limit pull down menu
	*
	* - Default setting is (10, 25, 50, 100)
	*
	* @param int $new_limits array of limits
	*/
	function setLimits($new_limits) {
		$this->limits = $new_limits;
	}
	
	/**
	* Sets the name of the class to be used for the links
	*
	* - Default setting is null
	*
	* @param string $link_class name of class
	*/
	function setLinkClass($link_class) {
		$this->link_class = $link_class;
	}
	
	/**
	* Sets the name of the class to be used for the pull down box
	*
	* - Default setting is null
	*
	* @param string $tb_class name of class
	*/
	function setTbClass($tb_class) {
		$this->tb_class = $tb_class;
	}
	
	/**
	* Sets the inline style of the limit jump menu
	* This setting overrides the tb_class value
	*
	* - Default setting is null
	* @param string $tb_style style of limit jump menu box
	*/
	function setTbStyle($tb_style) {
		$this->tb_style = $tb_style;
	}
	
	/**
	* Sets the name of the class to be used for the text
	*  ie) "Page:" and "Per page:"
	* Should be used to modify all paging text font -amily, size, etc
	*
	* - Default setting is null
	*
	* @param string $text_class name of class
	*/
	function setTextClass($text_class) {
		$this->text_class = $text_class;
	}
	
	/**
	* Sets the inline style to be used for the text
	* Should be used to modifiy all paging text font-family, size, etc
	* This will override the text_class setting
	*
	* - Default setting is null
	*
	* @param string $text_style style to use for the text
	*/
	function setTextStyle($text_style) {
		$this->text_style = $text_style;
	}
	
	/**
	* Sets the width of the table bounding the pages/jump box
	*
	* - Default setting is "100%"
	*
	* @param string $table_width width of table
	*/
	function setTableWidth($table_width) {
		$this->table_width = $table_width;
	}
	
	/**
	* Sets the horizontial alignment of the table bounding the paging
	*
	* - Default setting is "center"
	*
	* @param string $table_align alignment value for table align
	*/
	function setTableAlign($table_align) {
		$this->table_align = $table_align;
	}
	
	/**
	* Sets the page variable name for the querystring
	* @param string $page_var page variable name
	*/
	function setPageVar($page_var) {
		$this->page_var = $page_var;
	}
	
	/**
	* Sets the limit variable name for the querystring
	* @param string $limit_var limit variable name
	*/
	function setLimitVar($limit_var) {
		$this->limit_var = $limit_var;
	}
	
	/**
	* Sets the print_limit_select variable to decide if we should show the limit select pulldown
	* @param bool $view_limit_select if we should show the select pulldown or not
	*/
	function setViewLimitSelect($view_limit_select) {
		$this->print_limit_select = $view_limit_select;
	}
	//============================================
	
	//--------------------------------------------
	// Getter methods
	//--------------------------------------------	
	/**
	* Returns the recordset offset
	* @param none
	* @return integer recorset offset
	*/
	function getOffset() {
		return $this->limit * $this->cur_page - $this->limit;
	}
	
	/**
	* Returns the total number of pages
	* @param none
	* @return integer number of pages total
	*/
	function getTotPages() {
		return $this->tot_pages;
	}
	
	/**
	* Returns the current page number
	* @param none
	* @return integer current page number
	*/
	function getPageNum() {
		return $this->cur_page;
	}
	
	/**
	* Returns the current recordset limit
	* @param none
	* @return integer recordset limit
	*/
	function getLimit() {
		return $this->limit;
	}
	
	/**
	* Returns value of previous link text
	* @param none
	* @return string previous link text
	*/
	function getPrevLink() {
		return $this->prev_link;
	}
	
	/**
	* Returns value of next link text
	* @param none
	* @return string next link text
	*/
	function getNextLink() {
		return $this->next_link;
	}
	
	/**
	* Returns the name used for the page querystring variable
	* @param none
	* @return string page variable name
	*/
	function getPageVar() {
		return $this->page_var;
	}
	
	/**
	* Returns the name used for the limit querystring variable
	* @param none
	* @return string limit variable name
	*/
	function getLimitVar() {
		return $this->limit_var;
	}
	//===========================================
	
// End class
}
?>