Automate switching between languages

src/main/java/app/Main.java

@@ -9,41 +9,70 @@ import javafx.scene.Scene;
 import javafx.scene.image.Image;
 import javafx.stage.Stage;
 
+import app.events.LanguageChangedEvent;
+import app.model.Model;
+
 public class Main extends Application {
 
+  private Stage window;
+  private Scene scene;
+  private FXMLLoader fxmlLoader;
+  private Parent fxmlRoot;
+
+  private static final String TITLE = "Banana Editor";
+  private static final String ICON_PATH = "/graphics/logo.png";
+
   /**
-   * Boilerplate function to launch the application
+   * Boilerplate function to launch the application.
    */
   public static void main(String[] args) {
     launch(args);
   }
 
   /**
-   * The entrypoint of the application
+   * Set up a window with title and icon.
+   */
+  private void setupWindow(Stage window) {
+    this.window = window;
+    window.setTitle(TITLE);
+    window.getIcons().add(new Image(getClass().getResourceAsStream(ICON_PATH)));
+  }
+
+  private void loadFXML() throws IOException {
+    this.fxmlLoader = new FXMLLoader(getClass().getResource("/fxml/Main.fxml"));
+    this.fxmlRoot = fxmlLoader.load();
+  }
+
+  private void createScene() {
+    this.scene = new Scene(fxmlRoot);
+    Model.setScene(scene);
+  }
+
+  private void applyCSS() {
+    scene.getStylesheets().add(
+      getClass().getResource("/styling/app.css").toExternalForm());
+  }
+
+  /**
+   * Set up default values and settings for the editor.
+   */
+  private void setupDefaults() {
+    MainController mainController = fxmlLoader.getController();
+    mainController.getEventBus().post(new LanguageChangedEvent("Java"));
+  }
+
+  /**
+   * The entrypoint of the application.
    * @param window The primary window of the application
    */
   @Override
   public void start(Stage window) throws IOException {
-    window.setTitle("Banana Editor");
 
-    window.getIcons().add(new Image(getClass().getResourceAsStream("/graphics/logo.png")));
-
-    FXMLLoader fxmlLoader = new FXMLLoader(getClass().getResource("/fxml/Main.fxml"));
-    Parent document;
-
-    try {
-      document = fxmlLoader.load();
-    } catch (IOException e) {
-      System.err.println(e);
-      throw new RuntimeException(
-        "Couldn\'t find or missing permissions to load "
-        + getClass().getResource("/fxml/Main.fxml")
-      );
-    }
-
-    Scene scene = new Scene(document);
-
-    scene.getStylesheets().add(getClass().getResource("/styling/app.css").toExternalForm());
+    setupWindow(window);
+    loadFXML();
+    createScene();
+    applyCSS();
+    setupDefaults();
 
     window.setScene(scene);
     window.show();

src/main/java/app/MainController.java

@@ -5,8 +5,10 @@ import java.util.List;
 import java.util.ResourceBundle;
 
 import com.google.common.eventbus.EventBus;
+import com.google.common.eventbus.Subscribe;
 
 import app.controllers.*;
+import app.events.LanguageChangedEvent;
 import app.model.Model;
 import javafx.fxml.FXML;
 import javafx.fxml.Initializable;
@@ -26,11 +28,11 @@ public class MainController implements Initializable {
   private MenubarController menubarController;
 
   private EventBus eventBus;
-  private Model model;
 
   @Override
   public void initialize(URL url, ResourceBundle resourceBundle) {
     this.eventBus = new EventBus();
+    this.eventBus.register(this);
 
     List.of(
       editorController,
@@ -38,18 +40,35 @@ public class MainController implements Initializable {
       modelineController,
       menubarController
     ).forEach(c -> c.setEventBus(this.eventBus));
+
   }
 
+  /**
+   * Get the global eventbus.
+   * @return The eventbus
+   */
   public EventBus getEventBus() {
     return this.eventBus;
   }
 
   /**
-   * Links the controller to the global model
-   * @param model The model to be linked
+   * Change the CSS according to which language is being used.
+   * @param event The event containing data about the language to switch to
    */
-  public void setModel(Model model) {
-    this.model = model;
+  @Subscribe
+  private void handle(LanguageChangedEvent event) {
+
+    boolean containsSeveralStylesheets = Model.getScene().getStylesheets().size() != 1;
+
+    if (containsSeveralStylesheets)
+      Model.getScene().getStylesheets().remove(1);
+
+    String nextStyleSheet = 
+      getClass()
+        .getResource("/styling/language/" + event.getLanguage().toLowerCase() + ".css")
+        .toExternalForm();
+    
+    Model.getScene().getStylesheets().add(nextStyleSheet);
   }
 
 }

src/main/java/app/controllers/EditorController.java

@@ -5,6 +5,7 @@ import java.util.Collection;
 import java.util.ResourceBundle;
 
 import com.google.common.eventbus.EventBus;
+import com.google.common.eventbus.Subscribe;
 
 import org.fxmisc.richtext.CodeArea;
 import org.fxmisc.richtext.LineNumberFactory;
@@ -13,6 +14,7 @@ import org.fxmisc.richtext.model.TwoDimensional.Bias;
 import org.fxmisc.richtext.model.TwoDimensional.Position;
 
 import app.events.EditorChangedEvent;
+import app.events.LanguageChangedEvent;
 import app.model.Model;
 import app.service.LanguageOperations;
 import javafx.fxml.FXML;
@@ -39,20 +41,26 @@ public class EditorController implements Initializable, Controller {
   }
 
   /**
-   * Links the controller to the global model
-   * @param model The model to be linked
+   * Applies highlighting to the editor.
+   * @param highlighting highlighting data
    */
-  public void setModel(Model model) {
-    this.model = model;
-  }
-
-  public void setHighlighting(StyleSpans<Collection<String>> highlighting) {
+  private void setHighlighting(StyleSpans<Collection<String>> highlighting) {
     this.editor.setStyleSpans(0, highlighting);
   }
 
   /**
-   * Handles events from the editor, and reflects them in the model
-   * @param event The object containing metadata of the event
+   * Recalculates and refreshes the syntax highlighting of the editor.
+   */
+  private void refreshHighlighting() {
+    this.setHighlighting(
+      LanguageOperations.syntaxHighlight(
+        this.editor.getText(),
+        Model.getLanguage()));
+  }
+
+  /**
+   * Handles the event whenever the content of the editor is changed.
+   * @param event JavaFX event containing metadata
    */
   @FXML
   public void editorChanged(KeyEvent event) {
@@ -64,10 +72,16 @@ public class EditorController implements Initializable, Controller {
         pos.getMajor() + 1,
         pos.getMinor()
       ));
-    this.setHighlighting(
-      LanguageOperations.syntaxHighlight(
-        this.editor.getText(),
-        Model.getLanguage()));
+    this.refreshHighlighting();
+  }
+
+  /**
+   * Refreshes the editor whenever the language is changed.
+   * @param event Which language was switched to
+   */
+  @Subscribe
+  private void handle(LanguageChangedEvent event) {
+    this.refreshHighlighting();
   }
 
 }

src/main/java/app/controllers/MenubarController.java

@@ -5,11 +5,16 @@ import java.net.URL;
 import java.util.ResourceBundle;
 
 import com.google.common.eventbus.EventBus;
+import com.google.common.eventbus.Subscribe;
 
+import app.events.LanguageChangedEvent;
 import app.model.Model;
+import javafx.event.ActionEvent;
 import javafx.fxml.FXML;
 import javafx.fxml.Initializable;
 import javafx.scene.control.MenuBar;
+import javafx.scene.control.RadioMenuItem;
+import javafx.scene.control.ToggleGroup;
 import javafx.stage.DirectoryChooser;
 import javafx.stage.FileChooser;
 import javafx.stage.Stage;
@@ -17,11 +22,13 @@ import javafx.stage.Stage;
 public class MenubarController implements Initializable, Controller {
 
   private EventBus eventBus;
-  private Model model;
 
   @FXML
   private MenuBar menubar;
 
+  @FXML
+  private ToggleGroup languageToggleGroup;
+
   @FXML
   public String handleOpenFile() {
     FileChooser fc = new FileChooser();
@@ -76,12 +83,27 @@ public class MenubarController implements Initializable, Controller {
   }
 
   /**
-   * Links the controller to the global model
-   * 
-   * @param model The model to be linked
+   * Handles the event where the language was change from the menu.
    */
-  public void setModel(Model model) {
-    this.model = model;
+  @FXML
+  private void handleLanguageChange(ActionEvent event) {
+    this.eventBus.post(
+      new LanguageChangedEvent(
+        ((RadioMenuItem) event.getSource()).getText()));
   }
 
+  /**
+   * Updates menubuttons whenever the language is changed
+   */
+  @Subscribe
+  private void handle(LanguageChangedEvent event) {
+    this.languageToggleGroup
+      .getToggles()
+      .stream()
+      .map(RadioMenuItem.class::cast)
+      .filter(t -> t.getId().equals("toggle" + event.getLanguage()))
+      .findFirst()
+      .orElseThrow()
+      .setSelected(true);
+  }
 }

src/main/java/app/controllers/ModelineController.java

@@ -7,6 +7,7 @@ import com.google.common.eventbus.EventBus;
 import com.google.common.eventbus.Subscribe;
 
 import app.events.EditorChangedEvent;
+import app.events.LanguageChangedEvent;
 import app.model.Model;
 import javafx.fxml.FXML;
 import javafx.fxml.Initializable;
@@ -21,7 +22,6 @@ public class ModelineController implements Initializable, Controller {
   private Label language;
     
   private EventBus eventBus;
-  private Model model;
 
   @Override
   public void initialize(URL url, ResourceBundle resourceBundle) {
@@ -34,14 +34,6 @@ public class ModelineController implements Initializable, Controller {
     this.eventBus.register(this);
   }
 
-  /**
-   * Links the controller to the global model
-   * @param model The model to be linked
-   */
-  public void setModel(Model model) {
-    this.model = model;
-  }
-
   /**
    * Update the colum row counter
    * @param column The column number
@@ -51,9 +43,23 @@ public class ModelineController implements Initializable, Controller {
     this.columnrow.setText(String.format("[%d:%d]", row, column));
   }
 
+  /**
+   * Updates the column-row number display whenever the editor cursor
+   * changes position.
+   * @param event
+   */
   @Subscribe
-  public void handle(EditorChangedEvent event) {
-    System.out.println("Key pressed: " + event.getKeyCode());
+  private void handle(EditorChangedEvent event) {
     this.setColumnRow(event.getColumn(), event.getLineNumber());
   }
+
+  /**
+   * Updates the modeline to display a new language
+   * whenever it is changed.
+   * @param event
+   */
+  @Subscribe
+  private void handle(LanguageChangedEvent event) {
+    this.language.setText(event.getLanguage());
+  }
 }

src/main/java/app/events/EditorChangedEvent.java

@@ -2,7 +2,7 @@ package app.events;
 
 import javafx.scene.input.KeyCode;
 
-public class EditorChangedEvent implements Event {
+public class EditorChangedEvent extends Event {
   
   private KeyCode keyCode;
   private int lineNumber;

src/main/java/app/events/Event.java

@@ -1,3 +1,3 @@
 package app.events;
 
-interface Event {}
+class Event {}

src/main/java/app/events/LanguageChangedEvent.java

@@ -0,0 +1,33 @@
+package app.events;
+
+import app.languages.Java;
+import app.languages.Markdown;
+import app.model.Model;
+
+public class LanguageChangedEvent extends Event {
+
+  private String language;
+
+  public LanguageChangedEvent(String language) {
+    this.language = language;
+
+    switch (language) {
+
+      case "Java":
+        Model.setLanguage(new Java());
+        break;
+
+      case "Markdown":
+        Model.setLanguage(new Markdown());
+        break;
+
+      default:
+        break;
+    }
+  }
+
+  public String getLanguage() {
+    return language;
+  }
+  
+}

src/main/java/app/languages/Java.java

@@ -33,17 +33,20 @@ public class Java implements ProgrammingLanguage {
 
   private static final Map<Pattern, String> pattern = 
     Map.ofEntries(
-      e("\\b(" + String.join("|", keywords) + ")\\b", "keyword"), // <public>, <static>, ....
-      e("this", "this"),                          // <this>
-      e("true", "true"),                          // <true>
-      e("false", "false"),                        // <false>
-      e("\\(|\\)", "paranthesis"),                // <(*)>
-      e("\\{|\\}", "curlyBrackets"),              // <{*}>
-      e("\\[|\\]", "squareBrackets"),             // <[*]>
-      e(";", "semiColon"),                        // <;>
-      e("[A-Z]\\w+", "identifier"),               // <ClassName> or <InterfaceName>
-      e("\\.\\w+", "property"),                   // <.property>
-      e("(?<=this\\.)?\\w+(?=\\(*\\))", "method") // <this.function(*)>
+      e("\"([^\"\\\\]|\\\\.)*\"",     "string"),
+      e("\\bthis\\b",                 "this"),
+      e("\\btrue\\b",                 "true"),
+      e("\\bfalse\\b",                "false"),
+      e("(?<=\\.?)\\w+(?=\\()",       "method"),
+      e("\\(|\\)",                    "paranthesis"),
+      e("\\{|\\}",                    "curlyBrackets"),
+      e("\\[|\\]",                    "squareBrackets"),
+      e(";",                          "semicolon"),
+      e("\\.\\w+\\b(?!\\()",          "property"),
+      e("[A-Z]\\w+",                  "identifier"),
+      e("\\b(" + String.join("|", keywords) + ")\\b",
+                                      "keyword"),
+      e("(?://.*)|(?:\\/?\\s?\\*.*)", "comment")
     );
 
   public String getName() {
@@ -58,8 +61,6 @@ public class Java implements ProgrammingLanguage {
     return Java.pattern;
   }
 
-  // https://stackoverflow.com/questions/16517689/java-regex-capturing-groups-indexes/16582083
-
   public Pattern getPattern() {
     return Pattern.compile(
       Java.pattern

src/main/java/app/languages/Markdown.java

@@ -0,0 +1,60 @@
+package app.languages;
+
+import java.net.URL;
+import java.util.AbstractMap;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.regex.Pattern;
+import java.util.stream.Collectors;
+
+import app.model.ProgrammingLanguage;
+
+public class Markdown implements ProgrammingLanguage {
+
+  private String name = "Markdown";
+  private URL iconPath = this.getClass().getResource("");
+
+  private static Entry<Pattern, String> e(String k, String v) {
+    return new AbstractMap.SimpleEntry<>(Pattern.compile(k), v);
+  }
+
+  private static final Map<Pattern, String> pattern = 
+    Map.ofEntries(
+      e("##### .*", "ssssheader"),
+      e("#### .*", "sssheader"),
+      e("### .*", "ssheader"),
+      e("## .*", "sheader"),
+      e("# .*", "header"),
+      e("\\*\\*\\*.*\\*\\*\\*|___.*___", "emphasizedItalic"),
+      e("\\*\\*(?!\\*).*\\*\\*|__(?!_).*__", "emphasized"),
+      e("\\*(?!\\*).*\\*|_(?!_).*_", "italic"),
+      e("~~.*~~", "strikethrough"),
+      e("[\\-*+] .*", "listItem"),
+      e("\\d+\\. .*", "numberedItem"),
+      e("(?<!\\!)\\[.*\\][\\[\\()].*[\\)\\]]", "link"),
+      e("!\\[.*\\][\\[\\()].*[\\)\\]]", "image"),
+      e("\\[\\d+\\]: .*", "source")
+    );
+
+  public String getName() {
+    return this.name;
+  }
+
+  public URL getIcon() {
+    return this.iconPath;
+  }
+
+  public Map<Pattern, String> getPatternMap() {
+    return Markdown.pattern;
+  }
+
+  public Pattern getPattern() {
+    return Pattern.compile(
+      Markdown.pattern
+        .entrySet()
+        .stream()
+        .map(e -> String.format("(?<%s>%s)", e.getValue(), e.getKey()))
+        .collect(Collectors.joining("|")));
+  }
+
+}

src/main/java/app/model/Model.java

@@ -1,12 +1,18 @@
 package app.model;
 
+import javafx.scene.Scene;
+
 /**
- * Data model of the application
+ * Data model of the application.
+ * 
+ * Contains a static reference to state that has to be accessed
+ * by multiple pieces in the application, including the primary scene.
  */
 public class Model {
   private static String activeFilePath;
   private static String currentProjectPath;
   private static ProgrammingLanguage currentProgrammingLanguage;
+  private static Scene scene;
 
   public static String getActiveFilePath() {
     return activeFilePath;
@@ -20,7 +26,15 @@ public class Model {
     return currentProgrammingLanguage;
   }
 
+  public static Scene getScene() {
+    return scene;
+  }
+
   public static void setLanguage(ProgrammingLanguage language) {
     Model.currentProgrammingLanguage = language;
   }
+
+  public static void setScene(Scene scene) {
+    Model.scene = scene;
+  }
 }

src/main/resources/fxml/components/Menubar.fxml

@@ -5,6 +5,8 @@
 <?import javafx.scene.control.MenuItem?>
 <?import javafx.scene.control.Menu?>
 <?import javafx.scene.control.SeparatorMenuItem?>
+<?import javafx.scene.control.ToggleGroup?>
+<?import javafx.scene.control.RadioMenuItem?>
 
 <MenuBar
   fx:id="menubar"
@@ -24,10 +26,22 @@
         <MenuItem mnemonicParsing="false" text="Save" accelerator="Shortcut+s"/>
         <MenuItem mnemonicParsing="false" text="Save as" accelerator="Shortcut+S"/>
         <SeparatorMenuItem/>
+
+        <fx:define>
+          <ToggleGroup fx:id="languageToggleGroup"/>  
+        </fx:define>
+
         <Menu mnemonicParsing="false" text="Change programming language">
           <items>
-            <MenuItem mnemonicParsing="false" text="Java"/>
-            <MenuItem mnemonicParsing="false" text="Markdown"/>
+            <!-- TODO: Generate buttons based on classes -->
+            <RadioMenuItem text="Java"
+                           fx:id="toggleJava"
+                           onAction="#handleLanguageChange"
+                           toggleGroup="$languageToggleGroup"/>
+            <RadioMenuItem text="Markdown"
+                           fx:id="toggleMarkdown"
+                           onAction="#handleLanguageChange"
+                           toggleGroup="$languageToggleGroup"/>
           </items>
         </Menu>
         <SeparatorMenuItem/>

src/main/resources/styling/language/java.css

@@ -0,0 +1,61 @@
+
+.code-area .this {
+  -fx-fill: #FFFF00;
+  -fx-font-weight: bold;
+}
+
+.code-area .true {
+  -fx-fill: #00FF00;
+  -fx-font-weight: bold;
+}
+
+.code-area .false {
+  -fx-fill: #FF0000;
+  -fx-font-weight: bold;
+}
+
+.code-area .paranthesis {
+  -fx-fill: -main-fg-color;
+}
+
+.code-area .curlyBrackets {
+  -fx-fill: -main-fg-color;
+}
+
+.code-area .squareBrackets {
+  -fx-fill: -main-fg-color;
+}
+
+.code-area .semicolon {
+  -fx-fill: -main-fg-color;
+}
+
+.code-area .identifier {
+  -fx-fill: -main-blue-color;
+  -fx-font-weight: bold;
+}
+
+.code-area .property {
+  -fx-fill: -main-fg-color;
+}
+
+.code-area .method {
+  -fx-fill: -main-green-color;
+}
+
+.code-area .keyword {
+  -fx-fill: -main-red-color;
+  -fx-font-weight: bold;
+}
+
+.code-area .comment {
+  -fx-fill: -light-bg-color;
+}
+
+.code-area .string {
+  -fx-fill: -main-yellow-color;
+}
+
+.code-area .escapeChar {
+  -fx-fill: -main-magenta-color;
+}

src/main/resources/styling/language/markdown.css

@@ -0,0 +1,71 @@
+.code-area {
+  -test-color: #193814
+}
+
+.code-area .header {
+  -fx-fill: -main-green-color;
+  -fx-font-size: 200%;
+  -fx-font-weight: bold;
+}
+
+.code-area .sheader {
+  -fx-fill: -main-blue-color;
+  -fx-font-size: 150%;
+  -fx-font-weight: bold;
+}
+
+.code-area .ssheader {
+  -fx-fill: -main-red-color;
+  -fx-font-size: 130%;
+}
+
+.code-area .sssheader {
+  -fx-fill: -main-magenta-color;
+  -fx-font-size: 120%;
+}
+
+.code-area .ssssheader {
+  -fx-fill: -main-cyan-color;
+  -fx-font-size: 110%;
+}
+
+.code-area .emphasized {
+  -fx-fill: -main-blue-color;
+  -fx-font-weight: bold;
+}
+
+.code-area .italic {
+  -fx-fill: -main-cyan-color;
+  -fx-font-style: italic;
+}
+
+.code-area .emphasizedItalic {
+  -fx-fill: -main-magenta-color;
+  -fx-font-weight: bold;
+  -fx-font-style: italic;
+}
+
+.code-area .strikethrough {
+  -fx-fill: -main-red-color;
+  -fx-strikethrough: true;
+}
+
+.code-area .listItem {
+  -fx-fill: -main-yellow-color;
+}
+
+.code-area .numberedItem {
+  -fx-fill: -main-yellow-color;
+}
+
+.code-area .link {
+  -fx-fill: -main-red-color;
+}
+
+.code-area .image {
+  -fx-fill: -main-magenta-color;
+}
+
+.code-area .source {
+  -fx-fill: -main-magenta-color;
+}