package outpost

import (
	"context"
	"fmt"
)

func Example() {
	ctx := context.Background()
	st := &memStore{}

	// Request path: the message is appended in the same unit of work as the
	// business write. Here the store itself provides the appender.
	for _, to := range []string{"ada@example.com", "grace@example.com"} {
		err := Emit(ctx, st.appender(), "email.send",
			sendEmail{To: to, Subject: "welcome"}, Key(to))
		if err != nil {
			panic(err)
		}
	}

	// Worker path: the same handler runs whatever the producer is.
	d := NewDispatcher()
	Handle(d, "email.send", func(_ context.Context, e sendEmail) error {
		fmt.Println("send to", e.To)
		return nil
	})

	relay, err := NewRelay(st, ProducerFunc(d.Dispatch), WithWorkers(1))
	if err != nil {
		panic(err)
	}
	if _, err := relay.RunOnce(ctx); err != nil {
		panic(err)
	}

	// Output:
	// send to ada@example.com
	// send to grace@example.com
}