package js

import (
	"time"

	"github.com/dop251/goja"
)

type interval struct {
	goja.Callable
	this      goja.Value
	args      []goja.Value
	cancelled bool
	ticker    *time.Ticker
	stopChan  chan int
}

func (s *Simulator) setInterval(call goja.FunctionCall) goja.Value {
	fn, ok := goja.AssertFunction(call.Argument(0))
	if !ok {
		return nil
	}
	delay := call.Argument(1).ToInteger()
	var args []goja.Value
	if len(call.Arguments) > 2 {
		args = call.Arguments[2:]
	}

	i := &interval{
		Callable: fn,
		args:     args,
		ticker:   time.NewTicker(time.Duration(delay) * time.Millisecond),
		stopChan: make(chan int),
	}

	s.intervals = append(s.intervals, i)
	s.intervalsWg.Add(1)
	go func() {
		defer s.intervalsWg.Done()
		for {
			select {
			case <-i.stopChan:
				i.ticker.Stop()
				return
			case <-i.ticker.C:
				if i.cancelled {
					i.ticker.Stop()
					return
				}

				fn := func() {
					_, err := i.Callable(i.this, i.args...)
					if err != nil {
						s.m.Error(err)
					}
				}

				s.dispatchC <- fn
			}
		}
	}()

	return s.vm.ToValue(i)
}