package my_context

import (
	"context"
	"fmt"
	"net/http"
)

type Store interface {
	Fetch(ctx context.Context) (string, error)
	// instead of calling cancel we want to use context above to cross API boundries
	// Cancel()
}

func Server(store Store) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {

		// THIS WAS WHAT WE DID WHEN WE DIDN"T PROPOGATE CONTEXT
		// 	// This is the requests ctx not a derived context
		// 	ctx := r.Context()

		// 	data := make(chan string, 1)

		// 	go func() {
		// 		data <- store.Fetch()
		// 	}()

		// 	// Here we are simply waiting on the which channel
		// 	// will close out first. If the Done() channel on the request
		// 	// does store.Cancel() is called.

		// 	// Remember select lets use wait on multiple async operations and execute cases
		// 	// based on which one completes first as signaled by data being received on that channel.
		// 	select {
		// 	case d := <-data:
		// 		fmt.Fprint(w, d)
		// 	case <-ctx.Done():
		// 		store.Cancel()
		// 	}
		data, err := store.Fetch(r.Context())

		if err != nil {
			return // todo log the error however you like
		}
		fmt.Fprint(w, data)
	}
}