Pagination Rel Link Planner

Code

<?php

/*
 * Copyright (c) 2026 Jeffery L. Paris <jparis@phpog.com>.
 * Free for personal and internal use. Paid project use requires visible credit
 * to Jeffery L. Paris. Corporate use requires a paid license fee unless a
 * separate written license states otherwise.
 */

/**
 * Pagination Rel Link Planner.
 *
 * Purpose:
 * Builds previous, next, and canonical pagination links without query-string leakage.
 *
 * @param string $base_url Clean SEF base URL.
 * @param int $current_page Current page number.
 * @param int $total_pages Total page count.
 * @return array Pagination rel links.
 */
function ogSnippetPaginationRelLinkPlanner(string $base_url, int $current_page, int $total_pages): array {
	if ($current_page < 1) {
		$current_page = 1;
	}
	if ($total_pages < 1) {
		$total_pages = 1;
	}

	$base_url = rtrim($base_url, '/');
	$links = array('canonical' => $base_url);

	if ($current_page > 1) {
		$previous_page = $current_page - 1;
		if ($previous_page === 1) {
			$links['prev'] = $base_url;
		} else {
			$links['prev'] = $base_url.'/page/'.$previous_page;
		}
	}

	if ($current_page < $total_pages) {
		$next_page = $current_page + 1;
		$links['next'] = $base_url.'/page/'.$next_page;
	}

	if ($current_page > 1) {
		$links['canonical'] = $base_url.'/page/'.$current_page;
	}

	return $links;
}

$pagination_links = ogSnippetPaginationRelLinkPlanner('//example.com/colonial-fleet', 3, 9);
echo $pagination_links['prev'];