// Helene Martin, CSE 143
// Prompts the user for a file or directory name and shows
// a listing of all files and directories that can be reached from it.

import java.io.*;
import java.util.*;

public class Crawler {
   public static void main(String[] args) {
      Scanner console = new Scanner(System.in);
      System.out.print("directory or file name? ");
      String name = console.nextLine();
      File f = new File(name);
      if (!f.exists()) {
         System.out.println("That file or directory does not exist");
      } else {
         print(f);
      }
   }

   // Prints the name of the given file. If the file is a directory,
   // prints its content.
   // pre: f.exists()
   public static void print(File f) {
      print(f, 0);
   }

   // Prints the name of the given file at the specified level of indentation.
   // If the file is a directory, prints its content.
   // pre: f.exists()
   private static void print(File f, int level) {
      // could also pass indentation as a String
      for (int i = 0; i < level; i++) {
         System.out.print("    ");
      }
      System.out.println(f.getName());

      if (f.isDirectory()) {
         File[] contents = f.listFiles();
         for (int i = 0; i < contents.length; i++) {
            File current = contents[i];

            print(current, level + 1);
         }
      }
   }
}