package main

import (
	"context"
	"fmt"
	"html/template"

	//"io"
	"log/slog"
	"net/http"

	//"os"
	"strings"
	"time"
)

func IndexHandler(w http.ResponseWriter, r *http.Request) {

	files := []string{
		"./ui/html/base.go.tmpl",
		"./ui/html/index.go.tmpl",
	}

	ts, err := template.ParseFiles(files...)
	if err != nil {
		slog.Error("error parsing files", "error", err)
		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
		return
	}

	err = ts.ExecuteTemplate(w, "base", nil)
	if err != nil {
		slog.Error("error executing template", "error", err)
		http.Error(w, "Internal Server Error", http.StatusInternalServerError)
		return
	}
}

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 {
	fileServer := http.FileServer(http.Dir("./ui/static/"))
	mux := http.NewServeMux()
	mux.Handle("GET /static/", http.StripPrefix("/static", fileServer))
	mux.HandleFunc("GET /sse", SSEHandler)
	mux.HandleFunc("GET /{$}", IndexHandler)
	return mux
}

// TODO add args slice and process flags
// TODO add io.Writer and pass that to the logger
func run(ctx context.Context) 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()
	// TODO add os.Args
	if err := run(ctx); err != nil {
		slog.Error("an error occurred", "error", err)
	}
}