package simpleserver

import (
	"fmt"
	"io/ioutil"
	"net/http"
	"os"
	"os/signal"
	"path/filepath"
)

func setContentType(w http.ResponseWriter, ext string) {
	var t string
	switch ext {
	case ".html":
		t = "text/html"
	case ".js":
		t = "text/javascript"
	default:
		t = ""
	}
	if t != "" {
		w.Header().Add("Content-Type", t)
	}
}

func viewHandler(root string, w http.ResponseWriter, r *http.Request) {
	relativePath := filepath.FromSlash(r.URL.Path[1:])
	file := filepath.Join(root, relativePath)
	setContentType(w, filepath.Ext(relativePath))
	info, err := os.Stat(file)
	if err != nil {
		fmt.Fprint(w, err)
		return
	}
	if info.IsDir() {
		file = filepath.Join(file, "index.html")
	}
	fmt.Println("GET " + file)
	content, _ := ioutil.ReadFile(file)
	fmt.Fprint(w, string(content))
}

func Serve(root string) {
	address := "127.0.0.1:8000"
	fmt.Println("Serving " + root + " at http://" + address + " ...")
	fmt.Println("Use Ctrl+C to exit")
	fmt.Println("(This is not a production web server, don't get any funny ideas)")
	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) { viewHandler(root, w, r) })
	srv := &http.Server{Addr: address}
	c := make(chan os.Signal, 1)
	signal.Notify(c, os.Interrupt)
	go func() {
		<-c
		fmt.Println("Received interrupt, closing...")
		srv.Close()
	}()
	err := srv.ListenAndServe()
	if err != nil && err != http.ErrServerClosed {
		fmt.Fprintln(os.Stderr, err)
	}
}