<?php
/*
 * PHP Pagination Class
 *
 * @author David Carr - dave@daveismyname.com - http://www.daveismyname.com
 * @version 1.0
 * @date October 20, 2012
 */
class View_Paginator {

	/**
	 * set the number of items per page.
	 *
	 * @var numeric
	 */
	private $_perPage;

	/**
	 * set get parameter for fetching the page number
	 *
	 * @var string
	 */
	private $_instance;

	/**
	 * sets the page number.
	 *
	 * @var numeric
	 */
	private $_page;

	/**
	 * set the limit for the data source
	 *
	 * @var string
	 */
	private $_limit;

	/**
	 * set the total number of records/items.
	 *
	 * @var numeric
	 */
	private $_totalRows = 0;

	/**
	 * set custom css classes for additional flexibility
	 *
	 * @var sting
	 */
	private $_customCSS;



	/**
	 *  __construct
	 *
	 *  pass values when class is istantiated
	 *
	 * @param numeric $_perPage  sets the number of iteems per page
	 * @param numeric $_instance sets the instance for the GET parameter
	 */
	public function __construct( $perPage, $instance, $customCSS = '' ) {
		$this->_instance = $instance;
		$this->_perPage = $perPage;
		$this->set_instance();
		$this->_customCSS = $customCSS;
	}

	/**
	 * get_start
	 *
	 * creates the starting point for limiting the dataset
	 *
	 * @return numeric
	 */
	public function get_start() {
		return ( $this->_page * $this->_perPage ) - $this->_perPage;
	}

	/**
	 * set_instance
	 *
	 * sets the instance parameter, if numeric value is 0 then set to 1
	 *
	 * @var numeric
	 */
	private function set_instance() {
		$this->_page = (int) ( ! isset( $_GET[$this->_instance] ) ? 1 : (int)$_GET[$this->_instance] );
		$this->_page = ( $this->_page == 0 ? 1 : ($this->_page < 0 ? 1 : $this->_page) );
	}

	/**
	 * set_total
	 *
	 * collect a numberic value and assigns it to the totalRows
	 *
	 * @var numeric
	 */
	public function set_total( $_totalRows ) {
		$this->_totalRows = $_totalRows;
	}

	/**
	 * get_limit
	 *
	 * returns the limit for the data source, calling the get_start method and passing in the number of items perp page
	 *
	 * @return string
	 */
	public function get_limit() {
		return "LIMIT " . $this->get_start() . ",$this->_perPage";
	}

	/**
	 * get_limit_keys
	 *
	 * returns an array of the offset and limit returned on each call
	 *
	 * @return string
	 */
	public function get_limit_keys() {
		return ['offset' => $this->get_start(), 'limit' => $this->_perPage];
	}

	/**
	 * page_links
	 *
	 * create the html links for navigating through the dataset
	 *
	 * @var sting $path optionally set the path for the link
	 * @var sting $ext optionally pass in extra parameters to the GET
	 * @return string returns the html menu
	 */
	public function page_links( $path = '?', $ext = null ) {
		$adjacents = "2";
		$prev = $this->_page - 1;
		$next = $this->_page + 1;
		$lastpage = ceil( $this->_totalRows/$this->_perPage );
		$lpm1 = $lastpage - 1;

		$pagination = "";
		if ( $lastpage > 1 ) {
			$pagination .= "<ul class='pagination " . $this->_customCSS . "'>";
			if ( $this->_page > 1 ) {
				$pagination .= "<li><a href='" . $path . "$this->_instance=$prev" . "$ext'>". __( 'Previous', 'views-for-ninja-forms' ) . "</a></li>";
			}else {
				// $pagination.= "<span class='disabled'>Previous</span>";
			}

			if ( $lastpage < 7 + ( $adjacents * 2 ) ) {
				for ( $counter = 1; $counter <= $lastpage; $counter++ ) {
					if ( $counter == $this->_page )
						$pagination .= "<li><span class='current'>$counter</span></li>";
					else
						$pagination .= "<li><a href='" . $path . "$this->_instance=$counter" . "$ext'>$counter</a></li>";
				}
			}
			elseif ( $lastpage > 5 + ( $adjacents * 2 ) ) {
				if ( $this->_page < 1 + ( $adjacents * 2 ) ) {
					for ( $counter = 1; $counter < 2 + ( $adjacents * 2 ); $counter++ ) {
						if ( $counter == $this->_page )
							$pagination .= "<li><span class='current'>$counter</span></li>";
						else
							$pagination .= "<li><a href='" . $path . "$this->_instance=$counter" . "$ext'>$counter</a></li>";
					}
					$pagination .= "...";
					$pagination .= "<li><a href='" . $path . "$this->_instance=$lpm1" . "$ext'>$lpm1</a></li>";
					$pagination .= "<li><a href='" . $path . "$this->_instance=$lastpage" . "$ext'>$lastpage</a></li>";
				}
				elseif ( $lastpage - ( $adjacents * 2 ) > $this->_page && $this->_page > ( $adjacents * 2 ) ) {
					$pagination .= "<li><a href='" . $path . "$this->_instance=1" . "$ext'>1</a></li>";
					$pagination .= "<li><a href='" . $path . "$this->_instance=2" . "$ext'>2</a></li>";
					$pagination .= "...";
					for ( $counter = $this->_page - $adjacents; $counter <= $this->_page + $adjacents; $counter++ ) {
						if ( $counter == $this->_page )
							$pagination .= "<span class='current'>$counter</span>";
						else
							$pagination .= "<li><a href='" . $path . "$this->_instance=$counter" . "$ext'>$counter</a></li>";
					}
					$pagination .= "..";
					$pagination .= "<li><a href='" . $path . "$this->_instance=$lpm1" . "$ext'>$lpm1</a></li>";
					$pagination .= "<li><a href='" . $path . "$this->_instance=$lastpage" . "$ext'>$lastpage</a></li>";
				}
				else {
					$pagination .= "<li><a href='" . $path . "$this->_instance=1" . "$ext'>1</a></li>";
					$pagination .= "<li><a href='" . $path . "$this->_instance=2" . "$ext'>2</a></li>";
					$pagination .= "..";
					for ( $counter = $lastpage - ( 2 + ( $adjacents * 2 ) ); $counter <= $lastpage; $counter++ ) {
						if ( $counter == $this->_page )
							$pagination .= "<span class='current'>$counter</span>";
						else
							$pagination .= "<li><a href='" . $path . "$this->_instance=$counter" . "$ext'>$counter</a></li>";
					}
				}
			}

			if ( $this->_page < $counter - 1 )
				$pagination .= "<li><a href='" . $path . "$this->_instance=$next" . "$ext'>". __( 'Next', 'views-for-ninja-forms' ) . "</a></li>";
			else
				// $pagination.= "<li><span class='disabled'>Next</span></li>";
				$pagination .= "</ul>\n";
		}


		return $pagination;
	}
}
