Add Enhanced Keyboard Shortcut Mechanism (#91)

Reviewed-on: https://git.kske.dev/zdm/envoy/pulls/91
Reviewed-by: DieGurke <maxi@kske.dev>
Reviewed-by: kske <kai@kske.dev>

client/src/main/java/envoy/client/data/shortcuts/EnvoyShortcutConfig.java

@@ -0,0 +1,44 @@
+package envoy.client.data.shortcuts;
+
+import javafx.scene.input.*;
+
+import envoy.client.data.Context;
+import envoy.client.helper.ShutdownHelper;
+import envoy.client.ui.SceneContext.SceneInfo;
+import envoy.client.util.UserUtil;
+
+/**
+ * Envoy-specific implementation of the keyboard-shortcut interaction offered by
+ * {@link GlobalKeyShortcuts}.
+ *
+ * @author Leon Hofmeister
+ * @since Envoy Client v0.3-beta
+ */
+public class EnvoyShortcutConfig {
+
+	private EnvoyShortcutConfig() {}
+
+	/**
+	 * Supplies the default shortcuts for {@link GlobalKeyShortcuts}.
+	 *
+	 * @since Envoy Client v0.3-beta
+	 */
+	public static void initializeEnvoyShortcuts() {
+		final var instance = GlobalKeyShortcuts.getInstance();
+
+		// Add the option to exit with "Control" + "Q" or "Alt" + "F4" as offered by
+		// some desktop environments
+		instance.add(new KeyCodeCombination(KeyCode.Q, KeyCombination.CONTROL_DOWN), ShutdownHelper::exit);
+
+		// Add the option to logout using "Control"+"Shift"+"L" if not in login scene
+		instance.addForNotExcluded(new KeyCodeCombination(KeyCode.L, KeyCombination.CONTROL_DOWN, KeyCombination.SHIFT_DOWN),
+				UserUtil::logout,
+				SceneInfo.LOGIN_SCENE);
+
+		// Add option to open settings scene with "Control"+"S", if not in login scene
+		instance.addForNotExcluded(new KeyCodeCombination(KeyCode.S, KeyCombination.CONTROL_DOWN),
+				() -> Context.getInstance().getSceneContext().load(SceneInfo.SETTINGS_SCENE),
+				SceneInfo.SETTINGS_SCENE,
+				SceneInfo.LOGIN_SCENE);
+	}
+}

client/src/main/java/envoy/client/data/shortcuts/GlobalKeyShortcuts.java

@@ -0,0 +1,76 @@
+package envoy.client.data.shortcuts;
+
+import java.util.*;
+
+import javafx.scene.input.KeyCombination;
+
+import envoy.client.ui.SceneContext.SceneInfo;
+
+/**
+ * Contains all keyboard shortcuts used throughout the application.
+ *
+ * @author Leon Hofmeister
+ * @since Envoy Client v0.3-beta
+ */
+public final class GlobalKeyShortcuts {
+
+	private final EnumMap<SceneInfo, Map<KeyCombination, Runnable>> shortcuts = new EnumMap<>(SceneInfo.class);
+
+	private static GlobalKeyShortcuts instance = new GlobalKeyShortcuts();
+
+	private GlobalKeyShortcuts() {
+		for (final var sceneInfo : SceneInfo.values())
+			shortcuts.put(sceneInfo, new HashMap<KeyCombination, Runnable>());
+	}
+
+	/**
+	 * @return the instance of global keyboard shortcuts.
+	 * @since Envoy Client v0.3-beta
+	 */
+	public static GlobalKeyShortcuts getInstance() { return instance; }
+
+	/**
+	 * Adds the given keyboard shortcut and its action to all scenes.
+	 *
+	 * @param keys   the keys to press to perform the given action
+	 * @param action the action to perform
+	 * @since Envoy Client v0.3-beta
+	 */
+	public void add(KeyCombination keys, Runnable action) { shortcuts.values().forEach(collection -> collection.put(keys, action)); }
+
+	/**
+	 * Adds the given keyboard shortcut and its action to all scenes that are not
+	 * part of exclude.
+	 *
+	 * @param keys    the keys to press to perform the given action
+	 * @param action  the action to perform
+	 * @param exclude the scenes that should be excluded from receiving this
+	 *                keyboard shortcut
+	 * @since Envoy Client v0.3-beta
+	 */
+	public void addForNotExcluded(KeyCombination keys, Runnable action, SceneInfo... exclude) {
+
+		// Computing the remaining sceneInfos
+		final var	include	= new SceneInfo[SceneInfo.values().length - exclude.length];
+		int			index	= 0;
+		outer:
+		for (final var sceneInfo : SceneInfo.values()) {
+			for (final var excluded : exclude)
+				if (sceneInfo.equals(excluded)) continue outer;
+			include[index++] = sceneInfo;
+		}
+
+		// Adding the action to the remaining sceneInfos
+		for (final var sceneInfo : include)
+			shortcuts.get(sceneInfo).put(keys, action);
+	}
+
+	/**
+	 * Returns all stored keyboard shortcuts for the given scene constant.
+	 *
+	 * @param sceneInfo the currently loading scene
+	 * @return all stored keyboard shortcuts for this scene
+	 * @since Envoy Client v0.3-beta
+	 */
+	public Map<KeyCombination, Runnable> getKeyboardShortcuts(SceneInfo sceneInfo) { return shortcuts.get(sceneInfo); }
+}

client/src/main/java/envoy/client/data/shortcuts/KeyboardMapping.java

@@ -0,0 +1,25 @@
+package envoy.client.data.shortcuts;
+
+import java.util.Map;
+
+import javafx.scene.input.KeyCombination;
+
+import envoy.client.ui.SceneContext;
+
+/**
+ * Provides methods to set the keyboard shortcuts for a specific scene.
+ * Should only be implemented by controllers of scenes so that these methods can
+ * automatically be called inside {@link SceneContext} as soon
+ * as the underlying FXML file has been loaded.
+ *
+ * @author Leon Hofmeister
+ * @since Envoy Client v0.3-beta
+ */
+public interface KeyboardMapping {
+
+	/**
+	 * @return all keyboard shortcuts of a scene
+	 * @since Envoy Client v0.3-beta
+	 */
+	Map<KeyCombination, Runnable> getKeyboardShortcuts();
+}

client/src/main/java/envoy/client/data/shortcuts/package-info.java

@@ -0,0 +1,7 @@
+/**
+ * Contains the necessary classes to enable using keyboard shortcuts in Envoy.
+ *
+ * @author Leon Hofmeister
+ * @since Envoy Client v0.3-beta
+ */
+package envoy.client.data.shortcuts;