package http

import (
	"net/http"
	"os"
	"path"
	"strings"

	"github.com/pkg/errors"
	"gitlab.com/wpetit/goweb/logger"
)

func HTML5Fileserver(fs http.FileSystem) http.Handler {
	handler := http.FileServer(fs)

	fn := func(w http.ResponseWriter, r *http.Request) {
		urlPath := r.URL.Path
		if !strings.HasPrefix(urlPath, "/") {
			urlPath = "/" + urlPath
			r.URL.Path = urlPath
		}
		urlPath = path.Clean(urlPath)

		file, err := fs.Open(urlPath)
		if err != nil {
			if errors.Is(err, os.ErrNotExist) {
				r.URL.Path = "/"

				handler.ServeHTTP(w, r)
				return
			}

			logger.Error(r.Context(), "could not open bundle file", logger.CapturedE(err))

			http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
			return
		}

		defer func() {
			if err := file.Close(); err != nil {
				logger.Error(r.Context(), "could not close file", logger.CapturedE(err))

				http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)

				return
			}
		}()

		handler.ServeHTTP(w, r)
	}

	return http.HandlerFunc(fn)
}