[Editor] Enable auto-indentation and change indent size to 3

editor/src/main/kotlin/com/bartlomiejpluta/base/editor/code/component/CodeEditor.kt

@@ -4,6 +4,8 @@ import com.bartlomiejpluta.base.editor.code.highlighting.SyntaxHighlighter
 import javafx.beans.property.Property
 import javafx.beans.value.ObservableValue
 import javafx.concurrent.Task
+import javafx.scene.input.KeyCode
+import javafx.scene.input.KeyEvent
 import javafx.scene.layout.StackPane
 import org.fxmisc.flowless.VirtualizedScrollPane
 import org.fxmisc.richtext.CodeArea
@@ -39,9 +41,22 @@ class CodeEditor(private val highlighter: ObservableValue<out SyntaxHighlighter>
          .subscribe(this::applyHighlighting)
 
 
+
+      initAutoIndents()
+
       children += VirtualizedScrollPane(editor)
    }
 
+   private fun initAutoIndents() {
+      editor.addEventHandler(KeyEvent.KEY_PRESSED) { event ->
+         if (event.code === KeyCode.ENTER) {
+            WHITESPACE.find(editor.getParagraph(editor.currentParagraph - 1).segments[0])?.apply {
+               editor.insertText(editor.caretPosition, value)
+            }
+         }
+      }
+   }
+
    private fun computeHighlightingAsync(): Task<StyleSpans<Collection<String>>> {
       val code = editor.text
 
@@ -58,4 +73,8 @@ class CodeEditor(private val highlighter: ObservableValue<out SyntaxHighlighter>
    }
 
    override fun getUserAgentStylesheet(): String = highlighter.value.stylesheet.base64URL.toExternalForm()
+
+   companion object {
+      private val WHITESPACE = "^\\s+".toRegex()
+   }
 }

editor/src/main/kotlin/com/bartlomiejpluta/base/editor/code/stylesheet/JavaSyntaxHighlightingStylesheet.kt

@@ -13,7 +13,11 @@ class JavaSyntaxHighlightingStylesheet : Stylesheet() {
       val string by cssclass()
       val comment by cssclass()
       val paragraphBox by cssclass()
+      val paragraphText by cssclass()
+
       val hasCaret by csspseudoclass()
+
+      val tabSize by cssproperty<Int>("-fx-tab-size")
    }
 
    init {
@@ -52,5 +56,9 @@ class JavaSyntaxHighlightingStylesheet : Stylesheet() {
       paragraphBox and hasCaret {
          backgroundColor = multi(c("#f2f9fc"))
       }
+
+      paragraphText {
+         tabSize.value = 3
+      }
    }
 }