add more query builder features

README.md

@@ -39,3 +39,12 @@ $tasks = $tm->filter('project:hobby'); // empty
 ## API
 
 todo...
+
+### QueryBuilder
+
+```php
+$tasks = $taskManager->createQueryBuilder()
+    ->whereProject('hobby')
+    ->sortBy(QueryBuilder::SORT_ENTRY)
+    ->getResult()
+```

src/QueryBuilder.php

@@ -63,6 +63,30 @@ class QueryBuilder
         return $this->where('priority:' . $priority);
     }
 
+    /**
+     * @return $this
+     */
+    public function wherePriorityL()
+    {
+        return $this->wherePriority(Task::PRIORITY_LOW);
+    }
+
+    /**
+     * @return $this
+     */
+    public function wherePriorityM()
+    {
+        return $this->wherePriority(Task::PRIORITY_MEDIUM);
+    }
+
+    /**
+     * @return $this
+     */
+    public function wherePriorityH()
+    {
+        return $this->wherePriority(Task::PRIORITY_HIGH);
+    }
+
     /**
      * @param string $status
      * @return $this
@@ -72,6 +96,46 @@ class QueryBuilder
         return $this->where('status:' . $status);
     }
 
+    /**
+     * @return $this
+     */
+    public function wherePending()
+    {
+        return $this->whereStatus(Task::STATUS_PENDING);
+    }
+
+    /**
+     * @return $this
+     */
+    public function whereWaiting()
+    {
+        return $this->whereStatus(Task::STATUS_WAITING);
+    }
+
+    /**
+     * @return $this
+     */
+    public function whereCompleted()
+    {
+        return $this->whereStatus(Task::STATUS_COMPLETED);
+    }
+
+    /**
+     * @return $this
+     */
+    public function whereRecurring()
+    {
+        return $this->whereStatus(Task::STATUS_RECURRING);
+    }
+
+    /**
+     * @return $this
+     */
+    public function whereDeleted()
+    {
+        return $this->whereStatus(Task::STATUS_DELETED);
+    }
+
     /**
      * @param string $where
      * @return $this