Revert "[MM-8497] Ability to set Do Not Disturb for a specified period of time (#16067)" (#17657)

This reverts commit 77d42568f9.

model/scheduled_task.go

@@ -11,65 +11,42 @@ import (
 type TaskFunc func()
 
 type ScheduledTask struct {
-	Name                 string        `json:"name"`
-	Interval             time.Duration `json:"interval"`
-	Recurring            bool          `json:"recurring"`
-	function             func()
-	cancel               chan struct{}
-	cancelled            chan struct{}
-	fromNextIntervalTime bool
+	Name      string        `json:"name"`
+	Interval  time.Duration `json:"interval"`
+	Recurring bool          `json:"recurring"`
+	function  func()
+	cancel    chan struct{}
+	cancelled chan struct{}
 }
 
 func CreateTask(name string, function TaskFunc, timeToExecution time.Duration) *ScheduledTask {
-	return createTask(name, function, timeToExecution, false, false)
+	return createTask(name, function, timeToExecution, false)
 }
 
 func CreateRecurringTask(name string, function TaskFunc, interval time.Duration) *ScheduledTask {
-	return createTask(name, function, interval, true, false)
+	return createTask(name, function, interval, true)
 }
 
-func CreateRecurringTaskFromNextIntervalTime(name string, function TaskFunc, interval time.Duration) *ScheduledTask {
-	return createTask(name, function, interval, true, true)
-}
-
-func createTask(name string, function TaskFunc, interval time.Duration, recurring bool, fromNextIntervalTime bool) *ScheduledTask {
+func createTask(name string, function TaskFunc, interval time.Duration, recurring bool) *ScheduledTask {
 	task := &ScheduledTask{
-		Name:                 name,
-		Interval:             interval,
-		Recurring:            recurring,
-		function:             function,
-		cancel:               make(chan struct{}),
-		cancelled:            make(chan struct{}),
-		fromNextIntervalTime: fromNextIntervalTime,
+		Name:      name,
+		Interval:  interval,
+		Recurring: recurring,
+		function:  function,
+		cancel:    make(chan struct{}),
+		cancelled: make(chan struct{}),
 	}
 
 	go func() {
 		defer close(task.cancelled)
 
-		var firstTick <-chan time.Time
-		var ticker *time.Ticker
-
-		if task.fromNextIntervalTime {
-			currTime := time.Now()
-			first := currTime.Truncate(interval)
-			if first.Before(currTime) {
-				first = first.Add(interval)
-			}
-			firstTick = time.After(time.Until(first))
-			ticker = &time.Ticker{C: nil}
-		} else {
-			firstTick = nil
-			ticker = time.NewTicker(interval)
-		}
+		ticker := time.NewTicker(interval)
 		defer func() {
 			ticker.Stop()
 		}()
 
 		for {
 			select {
-			case <-firstTick:
-				ticker = time.NewTicker(interval)
-				function()
 			case <-ticker.C:
 				function()
 			case <-task.cancel: