apotrophos search bug solved
[living-lab-site.git] / application / models / videos_model.php
index 1ba9e8f..46efd10 100644 (file)
@@ -16,18 +16,24 @@ class Videos_model extends CI_Model {
                        $this->load->library('singleton_db');
                        $this->db = $this->singleton_db->connect();
                }
-               
-               $this->load->helper('url');
        }
        
        /**
         * Retrieves information about a set of videos which are going to be
         * displayed in the catalog.
         *
-        * TODO: filter, limit, ordering parameters
         * @param               int $category_id        DB category ID
         * @param               int $offset
         * @param               int $count
+        * @param               string $ordering        control videos ording by these
+        * possibilities:
+        * <ul>
+        *   <li><strong>'hottest':</strong> newest most appreciated first. An
+        *   appreciated video is one which has a bigger
+        *   score = views + likes - dislikes.</li>
+        *   <li><strong>'newest':</strong> newest first.</li>
+        *   <li><strong>'alphabetically':</strong> sort alphabetically.</li>
+        * </ul>
         * @return              array   a list of videos, each one being an assoc array with:
         * <ul>
         *   <li>id, name, title, duration, thumbs_count, default_thumb, views => from DB</li>
@@ -37,17 +43,34 @@ class Videos_model extends CI_Model {
         *   <li>thumbs => thumbnail images' URLs</li>
         * </ul>
         */
-       public function get_videos_summary($category_id, $offset, $count)
+       public function get_videos_summary($category_id, $offset, $count, $ordering = 'hottest')
        {
                $this->load->helper('text');
                
+               // Ordering
+               switch ($ordering)
+               {
+               case 'hottest':
+                       $order_statement = "ORDER BY date DESC, score DESC, RAND()";
+                       break;
+               case 'newest':
+                       $order_statement = "ORDER BY date DESC";
+                       break;
+               case 'alphabetically':
+                       $order_statement = "ORDER BY title";
+                       break;
+                       
+               default:
+                       $order_statement = "";
+               }
+               
                $query = $this->db->query(
-                       'SELECT id, name, title, duration, user_id, views, thumbs_count,
-                               default_thumb
+                       "SELECT id, name, title, duration, user_id, views, thumbs_count,
+                               default_thumb, (views + likes - dislikes) AS score
                        FROM `videos`
                        WHERE category_id = ?
-                       ORDER BY name
-                       LIMIT ?, ?', // TODO summary order 
+                       $order_statement
+                       LIMIT ?, ?", 
                        array(intval($category_id), $offset, $count)); 
                
                if ($query->num_rows() > 0)
@@ -85,7 +108,7 @@ class Videos_model extends CI_Model {
                        $category_id);
                
                if ($query->num_rows() > 0)
-                       return $row = $query->row()->count;
+                       return $query->row()->count;
                
                // Error
                return NULL;
@@ -200,6 +223,158 @@ class Videos_model extends CI_Model {
                
                return $thumbs;
        }
+
+       /**
+        * Searches videos in DB based on a search query string and returns an
+        * associative array of results.
+        * If count is zero the function only return the number of results.
+        * @param string $search_query
+        * @param int $offset
+        * @param int $count
+        * @param int $category_id      if NULL, all categories are searched
+        * @return array        an associative array with the same keys as that from
+        * get_videos_summary's result, but with two additional keys: 
+        * description and date.
+        */
+       public function search_videos($search_query, $offset = 0, $count = 0, 
+                                                                       $category_id = NULL)
+       {
+               $search_query = trim($search_query);
+               $search_query = str_replace("'", " ", $search_query);
+               
+               // Search word fragments.
+               // sfc = search fragment condition
+               $sfc = "( ";
+               // sfr = serach fragment relevation
+               $sfr = "( ";
+               $sep = ' +-*<>()~"';
+               $fragm = strtok($search_query, $sep);
+               while ($fragm !== FALSE)
+               {
+                       $sfc .= "(title LIKE '%$fragm%'
+                                       OR description LIKE '%$fragm%'
+                                       OR tags LIKE '%$fragm%') OR ";
+                       
+                       // Frament relevations are half of boolean relevations such
+                       // that they will appear at the end of the results.
+                       $sfr .= "0.25 * (title LIKE '%$fragm%')
+                                       + 0.1 * (description LIKE '%$fragm%')
+                                       + 0.15 * (tags LIKE '%$fragm%') + ";
+                       
+                       $fragm = strtok($sep);
+               }
+               $sfc = substr($sfc, 0, -4) . " )";
+               $sfr = substr($sfr, 0, -3) . " )";
+               
+               if (! $this->is_advanced_search_query($search_query))
+               {
+                       $search_cond = "MATCH (title, description, tags)
+                                       AGAINST ('$search_query') OR $sfc";
+                       $relevance = "( MATCH (title, description, tags)
+                                       AGAINST ('$search_query') + $sfr ) AS relevance";
+               }
+               // boolean mode
+               else
+               {
+                       $against = "AGAINST ('$search_query' IN BOOLEAN MODE)";
+                       $search_cond = "( MATCH (title, description, tags)
+                                       $against) OR $sfc";
+                       $relevance = "( 0.5 * (MATCH(title) $against)
+                                       + 0.3 * (MATCH(tags) $against)
+                                       + 0.2 * (MATCH(description) $against)
+                                       + $sfr) AS relevance";
+               }
+               
+               if ($count === 0)
+               {
+                       $selected_columns = "COUNT(*) count";
+                       $order = "";
+                       $limit = "";
+               }
+               else
+               {
+                       // TODO select data, description if details are needed
+                       $selected_columns = "id, name, title, duration, user_id, views,
+                                       thumbs_count, default_thumb,
+                                       (views + likes - dislikes) AS score, 
+                                       $relevance";
+                       $order = "ORDER BY relevance DESC, score DESC";
+                       $limit = "LIMIT $offset, $count";
+               }
+               
+               if ($category_id !== NULL)
+                       $category_cond = "category_id = '$category_id' AND ";
+               else
+                       $category_cond = "";
+
+               $str_query = "SELECT $selected_columns
+                       FROM `videos`
+                       WHERE  $category_cond $search_cond
+                       $order
+                       $limit";
+               //echo "<p>$str_query</p>";
+               $query = $this->db->query($str_query);
+               
+               if ($query->num_rows() > 0)
+               {
+                       if ($count === 0)
+                               return $query->row()->count;
+                       else
+                               $videos = $query->result_array();
+               }
+               else
+                       return NULL;
+               
+               $this->load->helper('text');
+               
+               foreach ($videos as & $video)
+               {
+                       // P2P-Tube Video URL
+                       $video['video_url'] = site_url(sprintf("watch/%d/%s",
+                               $video['id'], $video['name']));
+                       
+                       // Thumbnails
+                       $video['thumbs'] = $this->get_thumbs($video['name'], 
+                               $video['thumbs_count']);
+                               
+                       // Ellipsized title
+                       //$video['shorted_title'] = ellipsize($video['title'], 45, 0.75);
+                       $video['shorted_title'] = character_limiter($video['title'], 50);
+                       
+                       // TODO: user information
+                       $video['user_name'] = 'TODO';
+               }
+               
+               return $videos;
+       }
+       
+       public function decode_search_query($search_query)
+       {
+               $search_query = urldecode($search_query);
+               
+               $search_query = str_replace('_AST_', '*', $search_query);
+               $search_query = str_replace('_AND_', '+', $search_query);
+               $search_query = str_replace('_GT_', '>', $search_query);
+               $search_query = str_replace('_LT_', '<', $search_query);
+               $search_query = str_replace('_PO_', '(', $search_query);
+               $search_query = str_replace('_PC_', ')', $search_query);
+               $search_query = str_replace('_LOW_', '~', $search_query);
+               $search_query = str_replace('_QUO_', '"', $search_query);
+               
+               return $search_query;
+       }
+       
+       /**
+        * Return TRUE if it contains any special caracter from an advanced search
+        * query.
+        * @param string $search_query
+        * @return boolean
+        */
+       public function is_advanced_search_query($search_query)
+       {
+               return (preg_match('/\*|\+|\-|>|\<|\(|\)|~|"/', $search_query) == 0
+                       ? FALSE : TRUE);
+       }
 }
 
 /* End of file videos_model.php */