client/src/main/java/envoy/client/data/commands/SystemCommandMap.java

@@ -1,27 +1,53 @@
 package envoy.client.data.commands;
 
 import java.util.*;
+import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.function.Consumer;
 import java.util.logging.*;
 import java.util.regex.Pattern;
 import java.util.stream.Collectors;
 
+import javafx.application.Platform;
+import javafx.scene.control.Alert;
+import javafx.scene.control.Alert.AlertType;
+
 import envoy.util.EnvoyLog;
 
 /**
- * This class stores all {@link SystemCommand}s used.
+ * Stores all {@link SystemCommand}s used.
+ * SystemCommands can be called using an activator char and the text that needs
+ * to be present behind the activator.
+ * Additionally offers the option to request recommendations for a partial input
+ * String.
  *
  * @author Leon Hofmeister
  * @since Envoy Client v0.2-beta
  */
 public final class SystemCommandMap {
 
+	private final Character						activator;
 	private final Map<String, SystemCommand>	systemCommands	= new HashMap<>();
-
-	private final Pattern commandPattern = Pattern.compile("^[a-zA-Z0-9_:!\\(\\)\\?\\.\\,\\;\\-]+$");
+	private final Pattern						commandPattern	= Pattern.compile("^[a-zA-Z0-9_:!/\\(\\)\\?\\.\\,\\;\\-]+$");
 
 	private static final Logger logger = EnvoyLog.getLogger(SystemCommandMap.class);
 
+	/**
+	 * Creates a new {@code SystemCommandMap} with the given char as activator.
+	 * If this Character is null, any text used as input will be treated as a system
+	 * command.
+	 *
+	 * @param activator the char to use as activator for commands
+	 * @since Envoy Client v0.3-beta
+	 */
+	public SystemCommandMap(Character activator) { this.activator = activator; }
+
+	/**
+	 * Creates a new {@code SystemCommandMap} with '/' as activator.
+	 *
+	 * @since Envoy Client v0.3-beta
+	 */
+	public SystemCommandMap() { activator = '/'; }
+
 	/**
 	 * Adds a new command to the map if the command name is valid.
 	 *
@@ -39,19 +65,16 @@ public final class SystemCommandMap {
 	/**
 	 * This method checks if the input String is a key in the map and returns the
 	 * wrapped System command if present.
-	 * It will return an empty optional if the value after the slash is not a key in
-	 * the map, which is a valid case (i.e. input="3/4" and "4" is not a key in the
-	 * map).
 	 * <p>
 	 * Usage example:<br>
-	 * {@code SystemCommandMap systemCommands = new SystemCommandMap();}<br>
-	 * {@code Button button = new  Button();}
-	 * {@code systemCommands.add("example", text -> button.setText(text.get(0), 1);}<br>
+	 * {@code SystemCommandMap systemCommands = new SystemCommandMap('*');}<br>
+	 * {@code systemCommands.add("example", new SystemCommand(text -> {}, 1, null,
+	 * ""));}<br>
 	 * {@code ....}<br>
-	 * user input: {@code "/example xyz ..."}<br>
+	 * user input: {@code "*example xyz ..."}<br>
 	 * {@code systemCommands.get("example xyz ...")} or
-	 * {@code systemCommands.get("/example xyz ...")}
-	 * result: {@code Optional<SystemCommand>}
+	 * {@code systemCommands.get("*example xyz ...")}
+	 * result: {@code Optional<SystemCommand>.get() != null}
 	 *
 	 * @param input the input string given by the user
 	 * @return the wrapped system command, if present
@@ -60,33 +83,36 @@ public final class SystemCommandMap {
 	public Optional<SystemCommand> get(String input) { return Optional.ofNullable(systemCommands.get(getCommand(input.toLowerCase()))); }
 
 	/**
-	 * This method ensures that the "/" of a {@link SystemCommand} is stripped.<br>
+	 * This method ensures that the activator of a {@link SystemCommand} is
+	 * stripped.<br>
+	 * It only checks the word beginning from the first non-blank position in the
+	 * input.
 	 * It returns the command as (most likely) entered as key in the map for the
 	 * first word of the text.<br>
-	 * It should only be called on strings that contain a "/" at position 0/-1.
+	 * Activators in the middle of the word will be disregarded.
 	 *
 	 * @param raw the input
 	 * @return the command as entered in the map
 	 * @since Envoy Client v0.2-beta
 	 * @apiNote this method will (most likely) not return anything useful if
-	 *          whatever is entered after the slash is not a system command. Only
-	 *          exception: for recommendation purposes.
+	 *          whatever is entered after the activator is not a system command.
+	 *          Only exception: for recommendation purposes.
 	 */
 	public String getCommand(String raw) {
 		final var trimmed = raw.stripLeading();
 
-		// Entering only a slash should not throw an error
-		if (trimmed.length() == 1 && trimmed.charAt(0) == '/') return "";
+		// Entering only the activator should not throw an error
+		if (trimmed.length() == 1 && activator != null && activator.equals(trimmed.charAt(0))) return "";
 		else {
 			final var index = trimmed.indexOf(' ');
-			return trimmed.substring(trimmed.charAt(0) == '/' ? 1 : 0, index < 1 ? trimmed.length() : index);
+			return trimmed.substring(activator != null && activator.equals(trimmed.charAt(0)) ? 1 : 0, index < 1 ? trimmed.length() : index);
 		}
 	}
 
 	/**
 	 * Examines whether a key can be put in the map and logs it with
 	 * {@code Level.WARNING} if that key violates API constrictions.<br>
-	 * (allowed chars are <b>a-zA-Z0-9_:!()?.,;-</b>)
+	 * (allowed chars are <b>a-zA-Z0-9_:!/()?.,;-</b>)
 	 * <p>
 	 * The approach to not throw an exception was taken so that an ugly try-catch
 	 * block for every addition to the system commands map could be avoided, an
@@ -100,59 +126,86 @@ public final class SystemCommandMap {
 		final var valid = commandPattern.matcher(command).matches();
 		if (!valid) logger.log(Level.WARNING,
 				"The command \"" + command
-						+ "\" is not valid. As it will cause problems in execution, it will not be entered into the map. Only the characters "
+						+ "\" is not valid. As it might cause problems when executed, it will not be entered into the map. Only the characters "
 						+ commandPattern + "are allowed");
 		return valid;
 	}
 
 	/**
-	 * Takes a 'raw' string (the whole input) and checks if "/" is the first visible
-	 * character and then checks if a command is present after that "/". If that is
-	 * the case, it will be executed.
-	 * <p>
+	 * Takes a 'raw' string (the whole input) and checks if the activator is the
+	 * first visible character and then checks if a command is present after that
+	 * activator. If that is the case, it will be executed.
 	 *
 	 * @param raw the raw input string
-	 * @return whether a command could be found
+	 * @return whether a command could be found and successfully executed
 	 * @since Envoy Client v0.2-beta
 	 */
-	public boolean executeIfAnyPresent(String raw) {
+	public boolean executeIfPresent(String raw) {
+
 		// possibly a command was detected and could be executed
 		final var	raw2			= raw.stripLeading();
-		final var	commandFound	= raw2.startsWith("/") ? executeIfPresent(raw2) : false;
+		final var	commandFound	= activator == null || raw2.startsWith(activator.toString()) ? executeAvailableCommand(raw2) : false;
+
 		// the command was executed successfully - no further checking needed
 		if (commandFound) logger.log(Level.FINE, "executed system command " + getCommand(raw2));
 		return commandFound;
 	}
 
+	/**
+	 * Retrieves the recommendations based on the current input entered.<br>
+	 * The first word is used for the recommendations and
+	 * it does not matter if the activator is at its beginning or not.<br>
+	 * If recommendations are present, the given function will be executed on the
+	 * recommendations.<br>
+	 * Otherwise nothing will be done.<br>
+	 *
+	 * @param input  the input string
+	 * @param action the action that should be taken for the recommendations, if any
+	 *               are present
+	 * @since Envoy Client v0.2-beta
+	 */
+	public void requestRecommendations(String input, Consumer<Set<String>> action) {
+		final var partialCommand = getCommand(input);
+
+		// Get the expected commands
+		final var recommendations = recommendCommands(partialCommand);
+		if (recommendations.isEmpty()) return;
+
+		// Execute the given action
+		else action.accept(recommendations);
+	}
+
 	/**
 	 * This method checks if the input String is a key in the map and executes the
 	 * wrapped System command if present.
-	 * Its intended usage is after a "/" has been detected in the input String.
-	 * It will do nothing if the value after the slash is not a key in
-	 * the map, which is a valid case (i.e. input="3/4" and "4" is not a key in the
-	 * map).
 	 * <p>
 	 * Usage example:<br>
-	 * {@code SystemCommandMap systemCommands = new SystemCommandMap();}<br>
+	 * {@code SystemCommandMap systemCommands = new SystemCommandMap('*');}<br>
 	 * {@code Button button = new Button();}<br>
-	 * {@code systemCommands.add("example", (words)-> button.setText(words.get(0), 1);}<br>
+	 * {@code systemCommands.add("example", new SystemCommand(text ->
+	 * {button.setText(text.get(0))}, 1, null,
+	 * ""));}<br>
 	 * {@code ....}<br>
-	 * user input: {@code "/example xyz ..."}<br>
-	 * {@code systemCommands.executeIfPresent("example xyz ...")}
+	 * user input: {@code "*example xyz ..."}<br>
+	 * {@code systemCommands.executeIfPresent("example xyz ...")} or
+	 * {@code systemCommands.executeIfPresent("*example xyz ...")}
 	 * result: {@code button.getText()=="xyz"}
 	 *
 	 * @param input the input string given by the user
-	 * @return whether a command could be found
+	 * @return whether a command could be found and successfully executed
 	 * @since Envoy Client v0.2-beta
 	 */
-	public boolean executeIfPresent(String input) {
+	private boolean executeAvailableCommand(String input) {
 		final var	command			= getCommand(input);
 		final var	value			= get(command);
+		final var	commandExecuted	= new AtomicBoolean(value.isPresent());
 		value.ifPresent(systemCommand -> {
+
 			// Splitting the String so that the leading command including the first " " is
 			// removed and only as many following words as allowed by the system command
 			// persist
 			final var arguments = extractArguments(input, systemCommand);
+
 			// Executing the function
 			try {
 				systemCommand.call(arguments);
@@ -161,11 +214,23 @@ public final class SystemCommandMap {
 						String.format(
 								"System command %s could not be performed correctly because the user is a dumbass and could not write a parseable number.",
 								command));
+				Platform.runLater(() -> {
+					final var alert = new Alert(AlertType.ERROR);
+					alert.setContentText("Please enter a readable number as argument.");
+					alert.showAndWait();
+				});
+				commandExecuted.set(false);
 			} catch (final Exception e) {
 				logger.log(Level.WARNING, "System command " + command + " threw an exception: ", e);
+				Platform.runLater(() -> {
+					final var alert = new Alert(AlertType.ERROR);
+					alert.setContentText("Could not execute system command: Internal error. Please insult the responsible programmer.");
+					alert.showAndWait();
+				});
+				commandExecuted.set(false);
 			}
 		});
-		return value.isPresent();
+		return commandExecuted.get();
 	}
 
 	/**
@@ -177,12 +242,15 @@ public final class SystemCommandMap {
 	 * @since Envoy Client v0.2-beta
 	 */
 	private List<String> extractArguments(String input, SystemCommand systemCommand) {
+
 		// no more arguments follow after the command (e.g. text = "/DABR")
 		final var indexOfSpace = input.indexOf(" ");
 		if (indexOfSpace < 0) return supplementDefaults(new String[] {}, systemCommand);
+
 		// the arguments behind a system command
 		final var	remainingString		= input.substring(indexOfSpace + 1);
 		final var	numberOfArguments	= systemCommand.getNumberOfArguments();
+
 		// splitting those arguments and supplying default values
 		final var	textArguments		= remainingString.split(" ", -1);
 		final var	originalArguments	= numberOfArguments >= 0 ? Arrays.copyOfRange(textArguments, 0, numberOfArguments) : textArguments;
@@ -190,37 +258,17 @@ public final class SystemCommandMap {
 		return arguments;
 	}
 
-	/**
-	 * Retrieves the recommendations based on the current input entered.<br>
-	 * The first word is used for the recommendations and
-	 * it does not matter if the "/" is at its beginning or not.<br>
-	 * If none are present, nothing will be done.<br>
-	 * Otherwise the given function will be executed on the recommendations.<br>
-	 *
-	 * @param input  the input string
-	 * @param action the action that should be taken for the recommendations, if any
-	 *               are present
-	 * @since Envoy Client v0.2-beta
-	 */
-	public void requestRecommendations(String input, Consumer<Set<String>> action) {
-		final var partialCommand = getCommand(input);
-		// Get the expected commands
-		final var recommendations = recommendCommands(partialCommand);
-		if (recommendations.isEmpty()) return;
-		// Execute the given action
-		else action.accept(recommendations);
-	}
-
 	/**
 	 * Recommends commands based upon the currently entered input.<br>
-	 * In the current implementation, all we check is whether a key contains this
-	 * input. This might be updated later on.
+	 * In the current implementation, all that gets checked is whether a key
+	 * contains this input. This might be updated later on.
 	 *
 	 * @param partialCommand the partially entered command
 	 * @return a set of all commands that match this input
 	 * @since Envoy Client v0.2-beta
 	 */
 	private Set<String> recommendCommands(String partialCommand) {
+
 		// current implementation only looks if input is contained within a command,
 		// might be updated
 		return systemCommands.keySet()
@@ -231,11 +279,8 @@ public final class SystemCommandMap {
 	}
 
 	/**
-	 *
 	 * Supplies the default values for arguments if none are present in the text for
 	 * any argument. <br>
-	 * Will only work for {@code SystemCommand}s whose argument counter is bigger
-	 * than 1.
 	 *
 	 * @param textArguments the arguments that were parsed from the text
 	 * @param toEvaluate    the system command whose default values should be used
@@ -253,6 +298,7 @@ public final class SystemCommandMap {
 		if (toEvaluate.getNumberOfArguments() > 0) for (var index = 0; index < numberOfArguments; index++) {
 			String textArg = null;
 			if (index < textArguments.length) textArg = textArguments[index];
+
 			// Set the argument at position index to the current argument of the text, if it
 			// is present. Otherwise the default for that argument will be taken if present.
 			// In the worst case, an empty String will be used.
@@ -266,4 +312,10 @@ public final class SystemCommandMap {
 	 * @since Envoy Client v0.2-beta
 	 */
 	public Map<String, SystemCommand> getSystemCommands() { return systemCommands; }
+
+	/**
+	 * @return the activator of any command in this map. Can be null.
+	 * @since Envoy Client v0.3-beta
+	 */
+	public Character getActivator() { return activator; }
 }

client/src/main/java/envoy/client/ui/chatscene/ChatSceneCommands.java

@@ -40,6 +40,9 @@ public final class ChatSceneCommands {
 	public ChatSceneCommands(ListView<Message> messageList, ChatScene chatScene) {
 		this.messageList = messageList;
 
+		// Error message initialization
+		builder.setAction(text -> { throw new RuntimeException(); }).setDescription("Shows an error message.").buildNoArg("error");
+
 		// Do A Barrel roll initialization
 		final var random = new Random();
 		builder.setAction(text -> chatScene.doABarrelRoll(Integer.parseInt(text.get(0)), Double.parseDouble(text.get(1))))

client/src/main/java/envoy/client/ui/controller/ChatScene.java

@@ -625,7 +625,7 @@ public final class ChatScene implements EventListener, Restorable {
 			return;
 		}
 		final var text = messageTextArea.getText().strip();
-		if (!commands.getChatSceneCommands().executeIfAnyPresent(text)) {
+		if (!commands.getChatSceneCommands().executeIfPresent(text)) {
 			// Creating the message and its metadata
 			final var builder = new MessageBuilder(localDB.getUser().getID(), currentChat.getRecipient().getID(), localDB.getIDGenerator())
 				.setText(text);