package camfish

import "time"
import "context"

// cron is a built-in actor present in every environment that triggers routine
// tasks on time intervals.
type cron struct {
	trimFunc func() bool
	timing struct {
		trimInterval time.Duration
	}
}

var _ Actor        = new(cron)
var _ Runnable     = new(cron)
var _ Configurable = new(cron)

func (this *cron) Type () string {
	return "cron"
}

func (this *cron) Configure (config Config) error {
	if str := config.Get("trim-interval"); str != "" {
		value, err := time.ParseDuration(str)
		if err != nil {
			return NewConfigError(config, "trim-interval", 0, err)
		}
		this.timing.trimInterval = value
	}
	return nil
}

func (this *cron) Run (ctx context.Context) error {
	trimTicker := time.NewTicker(defaul(
		this.timing.trimInterval,
		defaultTrimInterval))
	defer trimTicker.Stop()
	for {
		select {
		case <- trimTicker.C:
			if this.trimFunc != nil {
				this.trimFunc()
			}
		case <- ctx.Done(): return ctx.Err()
		}
	}
}