Related posts - by tags and categories

gistfile1.txt

<?php
				$max_articles = 7;  // How many articles to display
				echo '<h3>Related Topics</h3><ul class="related-topics">';
				$cnt = 0;
            
				$article_tags = get_the_tags();
				$tags_string = '';
				if ($article_tags) {
					foreach ($article_tags as $article_tag) {
						$tags_string .= $article_tag->slug . ',';
					}
				}
        
				$tag_related_posts = get_posts('exclude=' . $post->ID . '&numberposts=' . $max_articles . '&tag=' . $tags_string);

				$used = array();
				array_push($used, $post->ID);
				
				
				if ($tag_related_posts) {
					foreach ($tag_related_posts as $related_post) {
						$cnt++; 
						echo '<li class="child-' . $cnt . '">';
						echo '<a href="' . get_permalink($related_post->ID) . '">';
						echo $related_post->post_title . '</a></li>';
						array_push($used,$related_post->ID);
					}
				}
				
        
				// Only if there's not enough tag related articles,
				// we add some from the same category
            
				if ($cnt < $max_articles) {
					
					$article_categories = get_the_category($post->ID);
					$category_string = '';
					foreach($article_categories as $category) { 
						$category_string .= $category->cat_ID . ',';
					}
				
				
					$args=array(
					  'cat' => $category_string,
					  'post__not_in' => $used,
					  'showposts'=>$max_articles,
					  'caller_get_posts'=>1
					);
					$my_query = new WP_Query($args);
					if( $my_query->have_posts() ):
						while ($my_query->have_posts()) : $my_query->the_post();
							$cnt++; 
							if ($cnt > $max_articles) break;
							echo '<li class="child-' . $cnt . '">';
							echo '<a href="' . get_permalink() . '">';
							the_title();
							echo '</a></li>';
						endwhile;
					endif;
					wp_reset_postdata();
				}
            
				echo '</ul>';
             
				?>