fix a deadlock and some other bugs

app/distortioner.go

@@ -344,6 +344,9 @@ func main() {
 	priorityChatsStr := strings.Split(os.Getenv("DISTORTIONER_PRIORITY_CHATS"), ",")
 	priorityChats := make([]int64, len(priorityChatsStr))
 	for i, s := range priorityChatsStr {
+		if s == "" {
+			continue
+		}
 		priorityChats[i], err = strconv.ParseInt(s, 10, 64)
 		if err != nil {
 			logger.Fatal(err)

app/handler_helpers.go

@@ -137,6 +137,7 @@ func (d DistorterBot) SendMessage(c tb.Context, toSend interface{}, method Metho
 			b.Reply(message, NotEnoughRights)
 		case strings.Contains(err.Error(), "bot was blocked by the user (403)"):
 			d.videoWorker.BanUser(message.Chat.ID)
+			return nil, nil
 		case strings.Contains(err.Error(), "telegram: Bad Request: message to be replied not found (400)"):
 			return d.SendMessage(c, toSend, Send)
 		}

app/queue/honest_priority_queue.go

@@ -76,20 +76,11 @@ func (hjq *HonestJobQueue) Pop() *Job {
 
 	job := heap.Pop(&hjq.queue).(*Job)
 
-	if _, ok := hjq.banned[job.userID]; ok {
-		allBannedJobsExhausted := true
-		for _, queued := range hjq.queue {
-			if queued.userID == job.userID {
-				allBannedJobsExhausted = false
-				break
-			}
+	for _, ok := hjq.banned[job.userID]; ok; {
+		if hjq.queue.Len() == 0 {
+			return nil
 		}
-
-		if allBannedJobsExhausted {
-			delete(hjq.banned, job.userID)
-		}
-
-		return hjq.Pop()
+		job = heap.Pop(&hjq.queue).(*Job)
 	}
 
 	hjq.users[job.userID]--
@@ -134,6 +125,11 @@ func (hjq *HonestJobQueue) Push(userID int64, runnable func()) error {
 		return errors.New("You're distorting videos too often, wait until the previous ones have been processed")
 	}
 
+	// if a user sent us a message then we're clearly unbanned
+	if _, ok := hjq.banned[userID]; ok {
+		delete(hjq.banned, userID)
+	}
+
 	hjq.users[userID] = priority + 1
 
 	job := newJob(userID, priority, runnable)

app/tools/video_worker.go

@@ -29,7 +29,10 @@ func (vw *VideoWorker) BanUser(userID int64) {
 
 func (vw *VideoWorker) run() {
 	for range vw.messenger {
-		vw.queue.Pop().Run()
+		job := vw.queue.Pop()
+		if job != nil {
+			job.Run()
+		}
 	}
 }