Autostart contests only when they are running and the grade is matching. Fixes #74

src/core.rs

@@ -268,16 +268,6 @@ pub fn show_contest<T: MedalConnection>(conn: &T, contest_id: i32, session_token
 
     let mut opt_part = conn.get_participation(&session_token, contest_id);
 
-    // Autostart if appropriate
-    // TODO: Should participation start automatically for teacher? Even before the contest start?
-    // Should teachers have all time access or only the same limited amount of time?
-    // if opt_part.is_none() && (contest.duration == 0 || session.is_teacher) {
-    // TODO: Should autostart only happen in the contest time?
-    if opt_part.is_none() && contest.duration == 0 {
-        conn.new_participation(&session_token, contest_id).map_err(|_| MedalError::AccessDenied)?;
-        opt_part = Some(Participation { contest: contest_id, user: session.id, start: time::get_time() });
-    }
-
     let ci = ContestInfo { id: contest.id.unwrap(),
                            name: contest.name.clone(),
                            duration: contest.duration,
@@ -295,6 +285,15 @@ pub fn show_contest<T: MedalConnection>(conn: &T, contest_id: i32, session_token
     data.insert("has_duration".to_string(), to_json(&has_duration));
     data.insert("can_start".to_string(), to_json(&can_start));
 
+    // Autostart if appropriate
+    // TODO: Should participation start automatically for teacher? Even before the contest start?
+    // Should teachers have all time access or only the same limited amount of time?
+    // if opt_part.is_none() && (contest.duration == 0 || session.is_teacher) {
+    if opt_part.is_none() && contest.duration == 0 && constraints.contest_running && constraints.grade_matching {
+        conn.new_participation(&session_token, contest_id).map_err(|_| MedalError::AccessDenied)?;
+        opt_part = Some(Participation { contest: contest_id, user: session.id, start: time::get_time() });
+    }
+
     let now = time::get_time();
     if let Some(start) = contest.start {
         if now < start {