package main

import (
	"bytes"
	"flag"
	"fmt"
	"net/http"
	"os"
	"os/exec"
	"path/filepath"
)

var (
	listenAddress = flag.String("listen", "0.0.0.0:80", "Where the server listens for connections. [interface]:port")
	staticPath    = flag.String("static", "../", "Location of static files.")
	scriptPath    = flag.String("scripts", "./modules/shell_files", "Location of shell scripts used to gather stats.")
)

func init() {
	flag.Parse()
}

func main() {
	http.Handle("/", http.FileServer(http.Dir(*staticPath)))
	http.HandleFunc("/server/", func(w http.ResponseWriter, r *http.Request) {
		module := r.URL.Query().Get("module")
		script := filepath.Join(*scriptPath, module+".sh")
		if module == "" {
			http.Error(w, "No module specified, or requested module doesn't exist.", 406)
			return
		}

		// Execute the command
		cmd := exec.Command(script)
		var output bytes.Buffer
		cmd.Stdout = &output
		err := cmd.Run()
		if err != nil {
			fmt.Printf("Error executing '%s': %s\n\tScript output: %s\n", script, err.Error(), output.String())
			http.Error(w, "Unable to execute module.", http.StatusInternalServerError)
			return
		}

		w.Write(output.Bytes())
	})

	fmt.Println("Starting http server at:", *listenAddress)
	err := http.ListenAndServe(*listenAddress, nil)
	if err != nil {
		fmt.Println("Error starting http server:", err)
		os.Exit(1)
	}
}