Generate {{mustache}} ready data for pagination

function-get_pagination_data.php

<?php

/**
 * Returns {{mustache}} ready data for pagination
 *
 * Pagination array for `prev`, `next`, `start`, `end` and `jump`
 * to direct pages
 *
 * @author  Martin Adamko   <@martin_adamko>
 * @licence The MIT Licence <http://opensource.org/licenses/MIT>
 *
 * @param   array   $args   Settings
 * @returns array           Pagination data
 *
 */
function get_pagination_data(array $args=array())
{
    $defaults = array(
        'page'    => 1,
        'total'   => null,
        'perpage' => null,
        'type'    => 'paginate',
        'radius'  => 5,
        'uri'     => $_SERVER['REQUEST_URI'],
        'key'     => 'page'
    );

    // Remove undefined
    foreach ($args as $k => &$v) {
        if (empty($v)) {
            unset($args[$k]);
        }
    }

    $args = array_merge($defaults, $args);
    extract($args, EXTR_SKIP);

    // There is no pagination if...
    if ((int) $total<1 || (int) $page<1 || (int) $perpage<1 || (int) $total <= (int) $perpage) {
        return array();
    }

    // Shorthand
    $p =& $page;
    // Total pages
    $pages = ceil($total/$perpage);

    $pagination = array(
        'current' => $p,
        'total'   => $total,
    );

    if (($p-1) > 0) {
        $pagination['prev']  = array( 'link' => remove_query_arg($key, $uri));
        if ($p-1>1) {
            $pagination['start'] = array( 'link' =>  remove_query_arg($key, $uri));
        }
    }

    if ($p+1 <= ceil($total/$perpage)) {
        $pagination['next']  = array( 'link' => add_query_arg($key, $p+1, $uri));
        if ($p+1<$pages) {
            $pagination['end']   = array( 'link' => add_query_arg($key, $pages, $uri));
        }
    }

    $p_start = $p- (($radius-1)/2);
    $p_end   = $p_start+($radius-1);

    while($p_start <= 0) {
        $p_start++;
        $p_end++;
    }

    while($p_end > $pages) {
        $p_end--;
        if($p_start > 1) {
            $p_start--;
        }
    }

    for( $i = $p_start; $i <= $p_end; $i++) {
        $active = $i==$p ? true : false;
        $pagination['jump'][] = array( 'link' => ($i===1) ? remove_query_arg($key, $uri) : add_query_arg($key, $i, $uri), 'text'=>$i, 'active' => $active );
    }

    return $pagination;
}