Make selfoss navigable

daos/mysql/Items.php

@@ -239,6 +239,10 @@ public function get($options = array()) {
             && isset($options['offset_from_id'])
             && is_numeric($options['offset_from_id']) ) {
 
+            // discard offset as it makes no sense to mix offset pagination
+            // with seek pagination.
+            $options['offset'] = 0;
+
             $offset_from_datetime_sql = $this->stmt->datetime($options['offset_from_datetime']);
             $params[':offset_from_datetime'] = array(
                 $offset_from_datetime_sql, \PDO::PARAM_STR
@@ -278,7 +282,6 @@ public function get($options = array()) {
 
         // finalize items filter
         $where_sql = implode(' AND ', $where);
-        if( $where_ids != '' ) $where_sql = "(($where_sql) OR $where_ids)";
 
         // set limit
         if(!is_numeric($options['items']) || $options['items']>200)
@@ -296,12 +299,32 @@ public function get($options = array()) {
         $this->hasMore = count($result);
 
         // get items from database
-        return \F3::get('db')->exec('SELECT
-                    items.id, datetime, items.title AS title, content, unread, starred, source, thumbnail, icon, uid, link, updatetime, author, sources.title as sourcetitle, sources.tags as tags
-                   FROM '.\F3::get('db_prefix').'items AS items, '.\F3::get('db_prefix').'sources AS sources
-                   WHERE items.source=sources.id AND '.$where_sql.'
-                   ORDER BY items.datetime '.$order.'
-                   LIMIT ' . $options['items'] . ' OFFSET '. $options['offset'], $params);
+        $select = 'SELECT
+            items.id, datetime, items.title AS title, content, unread, starred, source, thumbnail, icon, uid, link, updatetime, author, sources.title as sourcetitle, sources.tags as tags
+            FROM '.\F3::get('db_prefix').'items AS items, '.\F3::get('db_prefix').'sources AS sources
+            WHERE items.source=sources.id AND';
+        $order = 'ORDER BY items.datetime,items.id '.$order;
+
+        if( $where_ids != '' ) {
+            // This UNION is required for the extra explicitely requested items
+            // to be included whether or not they would have been excluded by
+            // seek, filter, offset rules.
+            //
+            // SQLite note: the 'entries' SELECT is encapsulated into a
+            // SELECT * FROM (...) to fool the SQLite engine into not
+            // complaining about 'order by clause should come after union not
+            // before'.
+            $query = "SELECT * FROM (
+                        SELECT * FROM ($select $where_sql $order LIMIT " . $options['items'] . ' OFFSET '. $options['offset'] . ") AS entries
+                      UNION
+                        $select $where_ids
+                      ) AS items
+                      $order";
+        } else {
+            $query = "$select $where_sql $order LIMIT " . $options['items'] . ' OFFSET '. $options['offset'];
+        }
+
+        return \F3::get('db')->exec($query, $params);
     }