package signaling

import (
	"sync"
	"time"
)

// AfterFunc-backed Timers, one per kind, firing Bridge.Timeout.
// Wiring is two-step because Bridge and timers want each other at
// construction: NewStdTimers, New(...), SetBridge.
type StdTimers struct {
	mu     sync.Mutex
	bridge *Bridge
	t      map[TimerKind]*time.Timer
}

func NewStdTimers() *StdTimers {
	return &StdTimers{t: make(map[TimerKind]*time.Timer)}
}

func (s *StdTimers) SetBridge(b *Bridge) {
	s.mu.Lock()
	defer s.mu.Unlock()
	s.bridge = b
}

func (s *StdTimers) Set(kind TimerKind, dur time.Duration) {
	s.mu.Lock()
	defer s.mu.Unlock()
	if old, ok := s.t[kind]; ok {
		old.Stop()
	}
	b := s.bridge
	s.t[kind] = time.AfterFunc(dur, func() {
		if b != nil {
			b.Timeout(kind)
		}
	})
}

func (s *StdTimers) Cancel(kind TimerKind) {
	s.mu.Lock()
	defer s.mu.Unlock()
	if old, ok := s.t[kind]; ok {
		old.Stop()
		delete(s.t, kind)
	}
}