add cron to loop

public/mytinytodo.js

@@ -1542,8 +1542,8 @@ function getGetParamValue(url, paramName) {
             prio: form.prio.value,
             tags: form.tags.value,
             duedate: form.duedate.value,
-            loop: form.loop.value
-            cron: form.cron.value
+            loop: form.loop.value,
+            cron: form.cron.value,
         }, function (json) {
             if (!parseInt(json.total)) return;
             form.task.value = '';

server/ajax/ajax.go

@@ -90,12 +90,17 @@ func (a *Ajax) Async() {
 	var err error
 	nextDue := time.Now().Add(config.Loop)
 	c := time.NewTicker(config.Loop)
+	c2 := time.NewTicker(config.Loop)
 	for {
+		c.Stop()
+		c.Reset(config.Loop)
+		c2.Stop()
+		c2.Reset(time.Until(nextDue))
+		log.Println("next loop at", time.Until(nextDue), "or", config.Loop)
 		select {
 		case <-c.C:
-		case <-time.After(time.Until(nextDue)):
+		case <-c2.C:
 		}
-		log.Println("loop tasks")
 		nextDue, err = a.loopTasks()
 		if err != nil {
 			log.Println("failed to loop tasks", err)
@@ -125,7 +130,10 @@ func (a *Ajax) loopTasks() (time.Time, error) {
 			}
 			nextLoopTrigger := task.Completed.Add(task.Loop)
 			if task.Loop == 0 {
-				nextLoopTrigger = task.Cron.Next()
+				nextLoopTrigger2 := task.Cron.Next(task.Completed)
+				if nextLoopTrigger2.Before(nextLoopTrigger) {
+					nextLoopTrigger = nextLoopTrigger2
+				}
 			}
 			if time.Now().Before(nextLoopTrigger) {
 				if nextLoopTrigger.Before(nextDue) {

server/ajax/form/cron.go

@@ -8,10 +8,10 @@ import (
 
 type Cron string
 
-func (c Cron) Next() time.Time {
+func (c Cron) Next(since time.Time) time.Time {
 	schedule, err := cron.ParseStandard(string(c))
 	if err != nil {
 		return time.Time{}
 	}
-	return schedule.Next(time.Now())
+	return schedule.Next(since)
 }