glossary template, lists posts alphabetiaclly and displays an alphabetical nav bar

glossary_template

<?php
/**
 * The glossary archive template
 */


/**
 * Remove the standard loop
 */
remove_action( 'genesis_loop', 'genesis_do_loop' );

add_action( 'genesis_loop', 'aha_glossary_loop' );
/**
 * Custom loop for glossary archive page
 */
function aha_glossary_loop() {
    
    //create navigation
        // get posts array
        $glossary_posts = get_posts(array('posts_per_page' => '-1', 'post_type' => 'glossary_term','orderby' => 'title', 'order' => 'ASC'));
        //print_r($glossary_posts);
        
        //create list of all distinct first letter
        $prev_letter = '';
        $distinct_letters = array();
        $i = 0;
        foreach ($glossary_posts as $term){
            $first_letter = substr($term->post_title, 0,1);
            if($first_letter != $prev_letter){
                $distinct_letters[$i] = $first_letter;
                $prev_letter = $first_letter;
                $i++;
            }

        }
        //print_r($distinct_letters);
        
        //display navigation

        echo '<ul id="glossary-nav">';
        foreach(range('A','Z') as $i){
            echo '<li>';
            if(in_array($i, $distinct_letters)){
                echo '<a href="#' . $i . '">' . $i . '</a>';
            }
            else
                echo $i;
            echo '</li>';

        }
        echo '</ul>';
        
        $prev_letter ='';
        $loop = new WP_Query(array('post_type' => array('glossary_term'), 'posts_per_page' => '-1', 'orderby' => 'title', 'order' => 'ASC'));
    if($loop->have_posts()) :
        while($loop->have_posts()):
            $loop->the_post();
            echo '<div class="post">';
            $first_letter = substr(get_the_title(), 0, 1);
            if($first_letter != $prev_letter)    {
                the_title('<a class="letter-index" id="' . $first_letter . '"></a><h2>','</h2>');
                $prev_letter = $first_letter;
                }
            else
                   the_title('<h2>','</h2>');             
            the_content();
            echo "</div>";
        endwhile;
    else :
        echo 'No documents matched the search criteria.';
    endif;

	genesis_posts_nav();
	
}

genesis();