birthdaybot/server/worker.go

package server

import (
	"time"

	"git.ctrlz.es/mgdelacroix/birthdaybot/model"
	"github.com/charmbracelet/log"
)

type Worker struct {
	server  *Server
	logger  *log.Logger
	stop    chan bool
	stopped chan bool
}

func NewWorker(server *Server) *Worker {
	return &Worker{
		server:  server,
		logger:  server.Logger,
		stop:    make(chan bool, 1),
		stopped: make(chan bool, 1),
	}
}

func (w *Worker) Start() {
	w.logger.Info("starting worker")
	go w.run()
	w.logger.Info("worker started")
}

func (w *Worker) Stop() {
	w.logger.Info("stopping worker")
	w.stop <- true
	<-w.stopped
	w.logger.Info("worker stopped")
}

func (w *Worker) notifyDay(year, month, day int) {
	birthdays := model.FilterByDate(w.server.Birthdays(), year, month, day)
	w.logger.Info("notifying for date", "birthdays", len(birthdays), "year", year, "month", month, "day", day)

	for _, b := range birthdays {
		w.logger.Info("notifying for birthday", "name", b.Name)
		w.server.Notify(b)
	}
}

func (w *Worker) run() {
	// first we calculate the delta with 23:00
	now := time.Now()
	eleven := time.Date(now.Year(), now.Month(), now.Day(), 23, 0, 0, 0, now.Location())

	if eleven.Before(now) {
		// tomorrow at 23:00
		eleven = time.Date(now.Year(), now.Month(), now.Day()+1, 23, 0, 0, 0, now.Location())
	}

	firstTick := eleven.Sub(now)

	var ticker *time.Ticker
	w.logger.Info("first timer tick set", "tick", firstTick)
	select {
	case <-time.After(firstTick):
		ticker = time.NewTicker(24 * time.Hour)
		w.notifyDay(eleven.Year(), int(eleven.Month()), eleven.Day())
	case <-w.stop:
		w.logger.Info("received stop signal")
		w.stopped <- true
		return
	}

	for {
		select {
		case t := <-ticker.C:
			w.logger.Info("ticker ticked for worker", "tick", t)
			w.notifyDay(t.Year(), int(t.Month()), t.Day())
		case <-w.stop:
			w.logger.Info("received stop signal")
			w.stopped <- true
			return
		}
	}
}