Index: wordpress-popular-posts.php
===================================================================
--- wordpress-popular-posts.php	(revision 724288)
+++ wordpress-popular-posts.php	(working copy)
@@ -827,27 +827,23 @@
             <?php
 			}
 		}
-		
+
 		/**
-		 * Builds popular posts list
-		 * Since 1.4.0
+		 * Build and run SQL query for popular posts
+		 *
+		 * @param array $instance widget instance
+		 * @return Array|NULL
 		 */
-		function get_popular_posts($instance, $return = false) {
-						
-			// update instance's settings			
-			$instance = $this->array_merge_recursive_distinct($this->defaults, $instance);			
-			/*echo "<pre>"; print_r($instance); echo "</pre>";*/
-			
+		function query_posts($instance) {
+			/** @var wpdb $wpdb */
 			global $wpdb;
 			$table = $wpdb->prefix . "popularpostsdata";
 			$fields = "";
 			$from = "";
-			$where = "";
 			$post_types = "";
 			$pids = "";
 			$cats = "";
 			$authors = "";
-			$content = "";
 			
 			// post filters			
 			// * post types - based on code seen at https://github.com/williamsba/WordPress-Popular-Posts-with-Custom-Post-Type-Support
@@ -859,22 +855,22 @@
 					
 			if ($len > 1) { // we are getting posts from more that one ctp				
 				foreach ( $types as $post_type ) {
-					$sql_post_types .= "'" .$post_type. "'";
+					$sql_post_types .= "'" .$post_type. "'";
 					
 					if ($i != $len - 1) $sql_post_types .= ",";
 					
 					$i++;
-				}
+				}
 
 				$post_types = " p.post_type IN({$sql_post_types}) ";
-			} else if ($len == 1) { // post from one ctp only
+			} else if ($len == 1) { // post from one ctp only
 			
 				$post_types = " p.post_type = '".$instance['post_type']."' ";
-				
+				
 				// if we're getting just pages, why join the categories table?
 				if ( strtolower($instance['post_type']) == 'page' )
 					$join_cats = false;
-				
+				
 			}
 			
 			// * posts exclusion
@@ -895,7 +891,7 @@
 				$in = array();
 				$out = array();
 				$not_in = "";
-				
+				
 				usort($cat_ids, array(&$this, 'sorter'));					
 				
 				for ($i=0; $i < count($cat_ids); $i++) {
@@ -910,40 +906,40 @@
 				if ($in_cats != "" && $out_cats == "") { // get posts from from given cats only
 					$cats = " AND p.ID IN (
 						SELECT object_id
-						FROM $wpdb->term_relationships AS r
-							 JOIN $wpdb->term_taxonomy AS x ON x.term_taxonomy_id = r.term_taxonomy_id
-							 JOIN $wpdb->terms AS t ON t.term_id = x.term_id
-						WHERE x.taxonomy = 'category' AND t.term_id IN($in_cats)
+						FROM {$wpdb->term_relationships} AS r
+							 JOIN {$wpdb->term_taxonomy} AS x ON x.term_taxonomy_id = r.term_taxonomy_id
+							 JOIN {$wpdb->terms} AS t ON t.term_id = x.term_id
+						WHERE x.taxonomy = 'category' AND t.term_id IN({$in_cats})
 						) ";
 				} else if ($in_cats == "" && $out_cats != "") { // exclude posts from given cats only
 					$cats = " AND p.ID NOT IN (
 						SELECT object_id
-						FROM $wpdb->term_relationships AS r
-							 JOIN $wpdb->term_taxonomy AS x ON x.term_taxonomy_id = r.term_taxonomy_id
-							 JOIN $wpdb->terms AS t ON t.term_id = x.term_id
-						WHERE x.taxonomy = 'category' AND t.term_id IN($out_cats)
+						FROM {$wpdb->term_relationships} AS r
+							 JOIN {$wpdb->term_taxonomy} AS x ON x.term_taxonomy_id = r.term_taxonomy_id
+							 JOIN {$wpdb->terms} AS t ON t.term_id = x.term_id
+						WHERE x.taxonomy = 'category' AND t.term_id IN({$out_cats})
 						) ";
 				} else { // mixed, and possibly a heavy load on the DB
 					$cats = " AND p.ID IN (
 						SELECT object_id
-						FROM $wpdb->term_relationships AS r
-							 JOIN $wpdb->term_taxonomy AS x ON x.term_taxonomy_id = r.term_taxonomy_id
-							 JOIN $wpdb->terms AS t ON t.term_id = x.term_id
-						WHERE x.taxonomy = 'category' AND t.term_id IN($in_cats) 
+						FROM {$wpdb->term_relationships} AS r
+							 JOIN {$wpdb->term_taxonomy} AS x ON x.term_taxonomy_id = r.term_taxonomy_id
+							 JOIN {$wpdb->terms} AS t ON t.term_id = x.term_id
+						WHERE x.taxonomy = 'category' AND t.term_id IN({$in_cats}) 
 						)) OR (p.post_type = 'post' AND p.ID NOT IN (
 						SELECT object_id
-						FROM $wpdb->term_relationships AS r
-							 JOIN $wpdb->term_taxonomy AS x ON x.term_taxonomy_id = r.term_taxonomy_id
-							 JOIN $wpdb->terms AS t ON t.term_id = x.term_id
-						WHERE x.taxonomy = 'category' AND t.term_id IN($out_cats)
+						FROM {$wpdb->term_relationships} AS r
+							 JOIN {$wpdb->term_taxonomy} AS x ON x.term_taxonomy_id = r.term_taxonomy_id
+							 JOIN {$wpdb->terms} AS t ON t.term_id = x.term_id
+						WHERE x.taxonomy = 'category' AND t.term_id IN({$out_cats})
 						) ";
 				}
 			}
 			
 			// * authors
 			if ( !empty($instance['author']) ) {			
-				$ath = explode(",", $instance['author']);			
-				$len = count($ath);
+				$ath = explode(",", $instance['author']);			
+				$len = count($ath);
 				
 				if ($len > 1) { // we are getting posts from more that one author
 					$authors = " AND p.post_author IN(".$instance['author'].") ";
@@ -1062,8 +1058,28 @@
 			//echo $query;
 			
 			$mostpopular = $wpdb->get_results($query);			
-			/*echo "<pre>"; print_r($mostpopular); echo "</pre>";*/
+
+			return $mostpopular;
+		}
+
+		/**
+		 * Builds popular posts list
+		 * Since 1.4.0
+		 */
+		function get_popular_posts($instance, $return = false) {
+			// update instance's settings
+			$instance = $this->array_merge_recursive_distinct($this->defaults, $instance);			
+			$content = "";
+
+			$mostpopular = $this->query_posts($instance);
+			/*echo "<pre>"; print_r($mostpopular); echo "</pre>";*/
 			
+			// If any theme or plugin want to apply custom markup and/or very special
+			// formatting let them creating a filter to build custom output.
+			if ($content = apply_filters('wpp_get_popular_posts_custom_display', $content, $mostpopular, $instance)) {
+				return $content;
+			}
+
 			if ( !is_array($mostpopular) || empty($mostpopular) ) { // no posts to show
 				$content .= "<p>".__('Sorry. No data so far.', 'wordpress-popular-posts')."</p>"."\n";
 			} else { // list posts