/*
 * Console.java
 *
 * Created on June 24, 2007, 3:24 PM
 *
 * To change this template, choose Tools | Template Manager
 * and open the template in the editor.
 */

//package browser;

import java .io.*;

abstract public class Console {

 	protected BufferedReader stdin;
	protected PrintWriter stdout;
	protected PrintWriter stderr;
	protected String prompt = "-> ";
	abstract protected String execute(String cmmd) throws AppError;

	public Console() {
		stdout = new PrintWriter(
			new BufferedWriter(
				new OutputStreamWriter(System.out)), true);
		stderr = new PrintWriter(
			new BufferedWriter(
				new OutputStreamWriter(System.out)), true);
		stdin = new BufferedReader(
			new InputStreamReader(System.in));
	}

	public void controlLoop() {

		boolean more = true;
		String cmmd = " ";
		String result = " ";
		String done = "done";
		stdout.println("type \"help\" for commands");

		while(more) {
			try {
				stdout.print(prompt);
				stdout.flush(); // force the write
				cmmd = stdin.readLine();

				if (cmmd.equals("quit")) {
					more = false;
				} else if (cmmd.equals("help")) {
					help();
				} else if (cmmd.equals("about")) {
					about();
				} else { // an application-specific command?
					result = execute(cmmd);
					stdout.println(result);
				}
			} catch(AppError exp) {
				more = handle(exp);
			} catch (IOException exp) {
				stderr.println("IO error, " + exp);
			} catch (Exception exp) {
				stderr.println("Serious error, " + exp);
				more = false;
			}
		} // while
		stdout.println("bye");
	} // controlLoop


	// overidables:
	protected void help() {
		stdout.println("Console Help Menu:");
		stdout.println("   about:   displays application information");
		stdout.println("   help:    displays this message");
		stdout.println("   quit:    terminate application");
	}
	protected void about() {
		stdout.println("Console Framework");
		stdout.println("copyright (c) 2001, all rights reserved\n");
	}
	protected boolean handle(AppError exp) {
		stderr.println("Application error, " + exp);
		return true;
	}
}