/* Java class having as its purpose to test instances of any class that
** implements the KeyPadLock interface.  Specifically, it has a method
** that, given a KeyPadLock object and a Scanner, reads one-character
** command/operation codes using the Scanner and applies the indicated 
** operations upon the given KeyPadLock object.  Each command code
** corresponds to a press of a key on the keypad of the lock, except
** for the QUIT command.
**
** The method produces a narration of events, describing each operation
** as it is applied and reporting the resulting state of the lock (open
** or closed) afterwards.
**
** The command codes are as follows:
**
**   q : quit (i.e., terminate program)
**   o : press OPEN key on the lock's keypad
**   c : press CLOSE key on the lock's keypad
**   0 : enter 0 on the lock's keypad
**   1 : enter 1 on the lock's keypad
**   .
**   .
**   9 : enter 9 on the lock's keypad
**
**  @version  October 2019.
**  @author R. McCloskey
*/

import java.util.Scanner;

public class KeyPadLockTester {

   private static final char SPACE = ' ';
   private static final char QUIT = 'q';
   private static final char OPEN = 'o';
   private static final char CLOSE = 'c';
   private static final String DIGITS = "0123456789";
   private static final String ALL_COMMANDS = DIGITS + QUIT + OPEN + CLOSE;

   /* Reads command codes using the given Scanner and applies them to
   ** the given KeyPadLock object, producing a narration of events.
   */
   public static void processCommands(KeyPadLock kpl, Scanner input) {

      boolean keepGoing = true;
      
      while ( keepGoing ) {
         System.out.print("Enter one or more commands: ");
         String commandStr = input.nextLine();
         //System.out.println(commandStr);
         int i = 0;
         while (keepGoing && i != commandStr.length()) {
            char command = commandStr.charAt(i); 
            if (command == SPACE) { i = i+1; }  // ignore spaces
            else if (ALL_COMMANDS.indexOf(command) == -1) {
               System.out.print("  Command " + command + " not recognized.");
               i = i+1;
            }
            else {
               System.out.print(" Performing command " + command);
               if (command == QUIT)
                  { keepGoing = false; }
               else {
                  try {
                     performCommand(kpl, command);
                     i = i+1;
                  }
                  catch (Exception e) {
                     System.out.println();
                     e.printStackTrace(System.out);
                     System.out.println();
                  }
               }
               String state = kpl.isOpen() ? "OPEN" : "CLOSED";
               System.out.print("; afterwards, lock is " + state);
            }
            System.out.println();
         }
      }
   }


   /* Performs the specified command upon the specified KeyPadLock.
   ** pre: command is either OPEN, CLOSE, or a digit.
   */
   private static void performCommand(KeyPadLock kpLock, char command) {

      if (command == OPEN) { kpLock.open(); }
      else if (command == CLOSE) { kpLock.close(); }
      else if (Character.isDigit(command)) { 
         kpLock.enterDigit( charToDig(command) );
      } 
      else {  // command is not recognized 
         System.out.println("This should never be printed!");
      }
   }


   /* pre:  c is in the range '0'..'9'
   ** post: value returned is the integer value corresponding to c.
   **      E.g., if c is (the char) '4', value returned will be (the int) 4.
   */
   private static int charToDig(char c) { return c - '0'; }

}