Calculate the time spent based on the timetable

app/Model/DateParser.php

@@ -12,6 +12,47 @@ use DateTime;
  */
 class DateParser extends Base
 {
+    /**
+     * Return true if the date is within the date range
+     *
+     * @access public
+     * @param  DateTime  $date
+     * @param  DateTime  $start
+     * @param  DateTime  $end
+     * @return boolean
+     */
+    public function withinDateRange(DateTime $date, DateTime $start, DateTime $end)
+    {
+        return $date >= $start && $date <= $end;
+    }
+
+    /**
+     * Get the total number of hours between 2 datetime objects
+     * Minutes are rounded to the nearest quarter
+     *
+     * @access public
+     * @param  DateTime $d1
+     * @param  DateTime $d2
+     * @return float
+     */
+    public function getHours(DateTime $d1, DateTime $d2)
+    {
+        $seconds = $this->getRoundedSeconds(abs($d1->getTimestamp() - $d2->getTimestamp()));
+        return round($seconds / 3600, 2);
+    }
+
+    /**
+     * Round the timestamp to the nearest quarter
+     *
+     * @access public
+     * @param  integer    $seconds   Timestamp
+     * @return integer
+     */
+    public function getRoundedSeconds($seconds)
+    {
+        return (int) round($seconds / (15 * 60)) * (15 * 60);
+    }
+
     /**
      * Return a timestamp if the given date format is correct otherwise return 0
      *