feat: Add timeout command to wait for a specified duration

Closes #86

Author: nihaltp

src/main/java/com/mycmd/App.java

@@ -108,5 +108,6 @@ private static void registerCommands(Map<String, Command> commands) {
         commands.put("set", new SetCommand());
         commands.put("systeminfo", new SysteminfoCommand());
         commands.put("pause", new PauseCommand());
+        commands.put("timeout", new TimeoutCommand());
     }
 }

src/main/java/com/mycmd/commands/TimeoutCommand.java

@@ -0,0 +1,130 @@
+package com.mycmd.commands;
+
+import com.mycmd.Command;
+import com.mycmd.ShellContext;
+import java.io.IOException;
+
+public class TimeoutCommand implements Command {
+    @Override
+    public void execute(String[] args, ShellContext context) {
+        int seconds = -1;
+        boolean hasSecondsArg = false;
+        boolean hasSlashT = false;
+        boolean noBreak = false;
+
+        for (int i = 0; i < args.length; i++) {
+            if (args[i].equalsIgnoreCase("/t")
+                    && i + 1 < args.length
+                    && args[i + 1].matches("[+-]?\\d+")) {
+                if (hasSlashT) {
+                    System.out.println(
+                            "Error: Invalid syntax. '/t' option is not allowed more than '1' time(s).");
+                    return;
+                }
+                seconds = Integer.parseInt(args[i + 1]);
+                i++;
+                hasSecondsArg = true;
+                hasSlashT = true;
+            } else if (args[i].equalsIgnoreCase("/nobreak")) {
+                if (noBreak) {
+                    System.out.println(
+                            "Error: Invalid syntax. '/nobreak' option is not allowed more than '1' time(s).");
+                    return;
+                }
+                noBreak = true;
+            } else if (args[i].matches("[+-]?\\d+")) {
+                if (hasSecondsArg) {
+                    System.out.println(
+                            "Error: Invalid syntax. Default option is not allowed more than '1' time(s).");
+                    return;
+                }
+                seconds = Integer.parseInt(args[i]);
+                hasSecondsArg = true;
+            } else if (args[i].equalsIgnoreCase("/t")) {
+                System.out.println("Error: Invalid syntax. Value expected for '/t'.");
+                return;
+            }
+        }
+
+        if (!hasSecondsArg) {
+            System.out.println("Error: Invalid syntax. Seconds value is required.");
+            return;
+        }
+
+        if (seconds < -1 || seconds > 99999) {
+            System.out.println(
+                    "Error: Invalid value for timeout specified. Valid range is 0-99999 seconds.");
+            return;
+        }
+
+        if (seconds == -1) {
+            System.out.println();
+            PauseCommand pauseCmd = new PauseCommand();
+            pauseCmd.execute(new String[0], context);
+            return;
+        }
+
+        Thread inputThread =
+                new Thread(
+                        () -> {
+                            try {
+                                System.in.read();
+                            } catch (IOException e) {
+                                // Ignore
+                            }
+                        });
+        inputThread.setDaemon(true);
+
+        if (!noBreak) {
+            inputThread.start();
+        }
+        System.out.println();
+
+        for (; seconds > 0; seconds--) {
+            if (!noBreak && !inputThread.isAlive()) {
+                System.out.println("\r");
+                System.out.println();
+                return;
+            }
+
+            System.out.print(
+                    "\rWaiting for "
+                            + seconds
+                            + " seconds, press "
+                            + (noBreak ? "CTRL+C to quit ..." : "enter key to continue ..."));
+            System.out.flush();
+            try {
+                Thread.sleep(1000);
+            } catch (InterruptedException e) {
+                if (noBreak) {
+                    continue;
+                }
+                System.out.println();
+                Thread.currentThread().interrupt();
+                break;
+            }
+        }
+        try {
+            while (System.in.available() > 0) {
+                System.in.read();
+            }
+        } catch (IOException e) {
+            // Ignore
+        }
+        System.out.println("\r");
+        System.out.println();
+    }
+
+    @Override
+    public String description() {
+        return "Sets a timeout for command execution.";
+    }
+
+    @Override
+    public String usage() {
+        return "timeout <seconds>\n"
+                + "timeout /t <seconds>\n"
+                + "timeout /t <seconds> /nobreak\n"
+                + "timeout /t -1";
+    }
+}