Replace class from span tag HTML DOM

I am trying to replace and add some value in the HTML class… I am success in solving this issue to some extent but now I need help. Here is my function code

function wpse247219_custom_pagination() {
    global $the_query;
    $big = 999999999; // need an unlikely integer
    $pages = paginate_links( array(
        'base' => str_replace( $big, '%#%', esc_url( get_pagenum_link( $big ) ) ),
        'format' => '?paged=%#%',
        'current' => max( 1, get_query_var('page') ),
        'total' => $the_query->max_num_pages,
        'prev_next' => false,
        'type'  => 'array',
        'prev_next'   => true,
        'prev_text'    => __( 'Previous', 'text-domain' ),
        'next_text'    => __( 'Next page', 'text-domain'),
    ) );
    $output = '';

    if ( is_array( $pages ) ) {
        $paged = ( get_query_var('paged') == 0 ) ? 1 : get_query_var( 'paged' );

        $output .=  '<ul class="pagination-list">';
        foreach ( $pages as $page ) {
            $output .= "<li>$page</li>";
        }
        $output .= '</ul>';
        $dom = new DOMDocument();
        $dom->loadHTML( mb_convert_encoding( $output, 'HTML-ENTITIES', 'UTF-8' ) );
        $xpath = new DOMXpath( $dom );
        $page_numbers = $xpath->query( "//*[contains(concat(' ', normalize-space(@class), ' '), ' page-numbers ')]" );
        foreach ( $page_numbers as $page_numbers_item ) {
            $page_numbers_item_classes = explode( ' ', $page_numbers_item->attributes->item(0)->value );

            if ( in_array( 'current', $page_numbers_item_classes ) ) {          
                $list_item_attr_class = $dom->createAttribute( 'class' );
                $list_item_attr_class->value = 'mynewclass';
                $page_numbers_item->parentNode->appendChild( $list_item_attr_class );
            }

            // Replace the class 'page-numbers' with 'page-link'
            $page_numbers_item->attributes->item(0)->value = str_replace( 
                            'page-numbers',
                            'pagination-link',
                            $page_numbers_item->attributes->item(0)->value );

                             // Replace the class 'page-numbers' with 'page-link'
            $page_numbers_item->attributes->item(0)->value = str_replace( 
                            'prev pagination-link',
                            'pagination-previous',
                            $page_numbers_item->attributes->item(0)->value );
        }


        // Save the updated HTML and output it.
        $output = $dom->saveHTML();
    }

    return $output;
}

this code currently output this modified Html Code

 <nav class="pagination is-rounded" role="navigation" aria-label="pagination">
    <ul class="pagination-list">
<li>
<a class="pagination-previous" href="https://blog.igsavers.com/page/3/">Previous</a></li>
<li><a class="pagination-link" href="https://blog.igsavers.com/page/1/">1</a></li>
<li><a class="pagination-link" href="https://blog.igsavers.com/page/2/">2</a></li>
<li><a class="pagination-link" href="https://blog.igsavers.com/page/3/">3</a></li>
<li><span aria-current="page" class="page-numbers current">4</span></li>
<li><a class="pagination-link" href="https://blog.igsavers.com/page/5/">5</a></li>
<li><a class="pagination-link" href="https://blog.igsavers.com/page/6/">6</a></li>
<li><span class="pagination-link dots">…</span></li>
<li><a class="pagination-link" href="https://blog.igsavers.com/page/11/">11</a></li>
<li><a class="next pagination-link" href="https://blog.igsavers.com/page/5/">Next page</a></li></ul>
    </nav>

And Now I Also want to replace the class of <span class="page-numbers current"> to <span class="pagination-link is-current "> so that it looks like this

I am also trying to remove <li></li> tag from the next and previous page button. any type of help will greatly be appreciated

Answer

After a some experiment with my code I solved my question. Here is my code…

function wpse247219_custom_pagination() {
    global $the_query;
    $big = 999999999; // need an unlikely integer
    $pages = paginate_links( array(
        'base' => str_replace( $big, '%#%', esc_url( get_pagenum_link( $big ) ) ),
        'format' => '?paged=%#%',
        'current' => max( 1, get_query_var('page') ),
        'total' => $the_query->max_num_pages,
        'prev_next' => false,
        'type'  => 'array',
        'prev_next'   => true,
        'prev_text'    => __( 'Previous', 'text-domain' ),
        'next_text'    => __( 'Next page', 'text-domain'),
    ) );
    $output = '';

    if ( is_array( $pages ) ) {
        $paged = ( get_query_var('paged') == 0 ) ? 1 : get_query_var( 'paged' );
        $size = count($pages)-1;
        $output .=  '<ul class="pagination-list">';
        $i = 0;
        foreach ( $pages as $page ) {
            if($i < 1 || $i == $size){
                $output .= "$page";
            }else{
                $output .= "<li>$page</li>";
            }
              $i++;  
        }
        $i = 0;
        $output .= '</ul>';
        $dom = new DOMDocument();
        $dom->loadHTML( mb_convert_encoding( $output, 'HTML-ENTITIES', 'UTF-8' ) );
        $xpath = new DOMXpath( $dom );
        $page_numbers = $xpath->query( "//*[contains(concat(' ', normalize-space(@class), ' '), ' page-numbers ')]" );
        foreach ( $page_numbers as $page_numbers_item ) {
            $page_numbers_item_classes = explode( ' ', $page_numbers_item->attributes->item(0)->value );
            if ( in_array( 'current', $page_numbers_item_classes ) ) {          
                $list_item_attr_class = $dom->createAttribute( 'class' );
                $list_item_attr_class->value = 'mynewclass';
                $page_numbers_item->parentNode->appendChild( $list_item_attr_class );
            }

            // Replace the class 'page-numbers' with 'page-link'
            $page_numbers_item->attributes->item(0)->value = str_replace( 
                            'page-numbers',
                            'pagination-link',
                            $page_numbers_item->attributes->item(0)->value );

                             // Replace the class 'page-numbers' with 'page-link'
            $page_numbers_item->attributes->item(0)->value = str_replace( 
                            'prev pagination-link',
                            'pagination-previous',
                            $page_numbers_item->attributes->item(0)->value );
        }
        $yupo = $xpath->query( "//*[contains(concat(' ', normalize-space(@class), ' '), ' page-numbers current')]" );
        foreach($yupo as $yup){
            $yup->attributes->item(1)->value = str_replace( 
                            'page-numbers current',
                            'pagination-link is-current',
                            $yup->attributes->item(1)->value );
        }


        // Save the updated HTML and output it.
        $output = $dom->saveHTML();
    }

    return $output;
}