paging.php

<?php
class Paging {
	public function get_paging_info($row_count, $page_length = 10, $page_num = 1, $max_page_num = 5) {
		$count = $row_count;
		if ($count == 0) {
			return "no data";
		}
		$page_num = $this->page_num_validation ( $page_num );
		$pages_count = $this->pages_count_validation ( ($count / $page_length) );
		$offset = $page_length * ($page_num - 1);
		$max_page_num = $this->max_page_num_validation ( $max_page_num, $pages_count );
		if ($count < $offset) {
			$page_length = 10;
			$offset = 0 * $page_length;
			$page_num = 1;
			$pages_count = 1;
		}
		$page_num_array = array ();
		$next_page = FALSE;
		$prev_page = FALSE;
		if ($pages_count > 1) {
			$next_page = ($pages_count >= ($page_num + 1)) ? $page_num + 1 : false;
			$prev_page = (($page_num - 1) > 0) ? $page_num - 1 : false;
			if ($max_page_num > 1) {
				$page_num_array = $this->getnumarray ( $page_num, $max_page_num, $pages_count );
			}
		}

	    return array (
				'page_num_array' => $page_num_array,
				'next_page' => $next_page,
				'prev_page' => $prev_page,
				'offset'=>$offset,
				'limit' =>$page_length
		);
	}
	private function page_num_validation($page_num) {
		return $page_num > 0 ? $page_num : 1;
	}
	private function pages_count_validation($pages_count) {
		$intval = intval ( $pages_count );
		if ($pages_count < 1) {
			$pages_count = 1;
		} else if ($intval < $pages_count) {
			$pages_count = $intval + 1;
		}
		return $pages_count;
	}
	private function max_page_num_validation($max_page_num, $pages_count) {
		if ($max_page_num < 2) {
			$max_page_num = 2;
		}
		if ($max_page_num > $pages_count) {
			$max_page_num = $pages_count;
			if ($max_page_num > 5) {
				$max_page_num = 5;
			}
		}
		return $max_page_num;
	}
	private function getnumarray($page_num, $max_page_num, $pages_count) {
		$page_num_array = array ();
		$gen_counter = 1;
		$last_val = $page_num;
		$page_num_array [] = $page_num;
		for($i = 1; $i <= $max_page_num - 1; $i ++) {
			$last_val ++;
			if ($last_val <= $pages_count) {
				$page_num_array [] = $page_num + $i;
				$gen_counter ++;
			}
		}
		for($i = 1; $i <= $max_page_num; $i ++) {
			$gen_counter ++;
			if ($gen_counter <= $max_page_num) {
				$page_num_array [] = $page_num - $i;
			} else {
				break;
			}
		}
		sort ( $page_num_array );

		return $page_num_array;
	}
}