package main

import (
	"context"
	"fmt"
	"io"
	"log/slog"
	"net/http"
	"os"
	"strings"
	"time"
)

func SSEHandler(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Content-Type", "text/event-stream")

	tokens := strings.Split("Hey there Drew. I hope you enjoy The Alters!", " ")
	for _, token := range tokens {
		w.Write([]byte(fmt.Sprintf("data: %s \n\n", token)))
		w.(http.Flusher).Flush()
		time.Sleep(time.Millisecond * 420)
	}
}

func routes() http.Handler {
	// TODO add static server and an HTML index with `new EventSource` JS that writes the data message contents into an element on the page
	mux := http.NewServeMux()
	mux.HandleFunc("/sse", SSEHandler)
	return mux
}

func run(ctx context.Context, w io.Writer, args []string) error {

	addr := fmt.Sprintf("%s:%d", "0.0.0.0", 8888)
	srv := &http.Server{
		Addr:    addr,
		Handler: routes(),
	}
	slog.Info("Listing on: http://0.0.0.0:8888")
	return srv.ListenAndServe()
}

func main() {
	ctx := context.Background()
	if err := run(ctx, os.Stdout, os.Args); err != nil {
		slog.Error("an error occurred", "error", err)
	}
}