Account for insets in layoutChildren()

[JordanMartinez]

Fixes #507

[JordanMartinez]

I want to address #508 in this PR as well since they are of similar nature.

Edit: Since that's a bit more complicated, I'm not going to address it here.

[JordanMartinez]

I'll also need to fix the implementation of firstLineOfArea() to use getCharacterBoundsOnScreen of the first letter.

[JordanMartinez]

Adding these hit tests revealed a bug in the code. I believe the issue is caused by VirtualFlow#hit not accounting for the possibility of padding.

[JordanMartinez]

Using this code:

import javafx.application.Application;
import javafx.geometry.Bounds;
import javafx.scene.Scene;
import javafx.scene.control.ContextMenu;
import javafx.scene.input.MouseEvent;
import javafx.stage.Stage;
import org.fxmisc.wellbehaved.event.EventPattern;
import org.fxmisc.wellbehaved.event.InputHandler;
import org.fxmisc.wellbehaved.event.InputMap;
import org.fxmisc.wellbehaved.event.Nodes;

public class TestGUI extends Application {

    public Stage stage;
    public Scene scene;
    public InlineCssTextArea area;
    public ContextMenu menu;

    @Override
    public void start(Stage stage) throws Exception {
        area = new InlineCssTextArea();
        scene = new Scene(area);
        this.stage = stage;

        stage.setScene(scene);
        stage.setWidth(400);
        stage.setHeight(400);
        stage.show();

        area.requestFocus();

        String text = "abcdefghijklmnopqrstuvwxyz";
        StringBuilder sb = new StringBuilder();
        for (int i = 0; i < 19; i++) {
            sb.append("Paragraph #").append(i).append(": ").append(text).append("\n");
        }
        sb.append(text);
        
        String fullText = sb.toString();
        area.replaceText(fullText);
        
//        area.setPadding(new Insets(20));
        area.setStyle("-fx-font-family: monospace; -fx-font-size: 12pt;");

        Bounds local = area.getBoundsInLocal();
        Bounds screen = area.localToScreen(local);
        System.out.println("Area bounds = " + screen);
        
        int start = area.getAbsolutePosition(3, 8);
        area.selectRange(start, start + 1);
        Bounds b = area.getCharacterBoundsOnScreen(start, start + 1).get();
        System.out.println("Bounds: " + b);
        
        Nodes.addInputMap(area, InputMap.process(EventPattern.mousePressed(), (MouseEvent e) -> {
            System.out.println("Mouse pressed | x: " + e.getScreenX() + ", y: " + e.getScreenY());
            System.out.println("Mouse | x: " + e.getX() + ", y: " + e.getY());
            return InputHandler.Result.PROCEED;
        }));
    }

}

Here is the output for the non-padded area (I clicked manually)

Area bounds = BoundingBox [minX:760.0, minY:217.66667315363884, minZ:0.0, width:100.0, height:100.0, depth:0.0, maxX:860.0, maxY:317.66667315363884, maxZ:0.0]
Bounds: BoundingBox [minX:838.5625010728836, minY:277.16667303442955, minZ:0.0, width:10.63280999660492, height:21.000000834465027, depth:0.0, maxX:849.1953110694885, maxY:298.1666738688946, maxZ:0.0]
Mouse pressed | x: 859.0, y: 329.0
Mouse | x: 98.0, y: 88.0
GenericStyleArea#hit called with arguments:  x: 98.0, y: 88.0
VirtualFlow.getCellIndex = 4
VirtualFLowHit.getCell().getNode().getParagraph() = Par[; StyledText[text="Paragraph #4: abcdefghijklmnopqrstuvwxyz", style=]]
VirtualFlowHit.getCellOffset() = x: 98.0, y: 8.0
Cell.hit(cellOffset) = getInsertionIndex(): 10, getCharacterIndex(): OptionalInt[9]
CharacterHit.offset(parOffset [164]) = org.fxmisc.richtext.CharacterHit@180e75e8

Here is the output for the padded area (also clicked manually)

Area bounds = BoundingBox [minX:760.0, minY:217.66667315363884, minZ:0.0, width:100.0, height:100.0, depth:0.0, maxX:860.0, maxY:317.66667315363884, maxZ:0.0]
Bounds: BoundingBox [minX:838.5625010728836, minY:277.16667303442955, minZ:0.0, width:10.63280999660492, height:21.000000834465027, depth:0.0, maxX:849.1953110694885, maxY:298.1666738688946, maxZ:0.0]
Mouse pressed | x: 839.0, y: 310.0
Mouse | x: 78.0, y: 69.0
GenericStyleArea#hit called with arguments:  x: 78.0, y: 69.0
VirtualFlow.getCellIndex = 3
VirtualFLowHit.getCell().getNode().getParagraph() = Par[; StyledText[text="Paragraph #3: abcdefghijklmnopqrstuvwxyz", style=]]
VirtualFlowHit.getCellOffset() = x: 78.0, y: 9.0
Cell.hit(cellOffset) = getInsertionIndex(): 8, getCharacterIndex(): OptionalInt[7]
CharacterHit.offset(parOffset [123]) = org.fxmisc.richtext.CharacterHit@29ca9beb

[JordanMartinez]

Aye, I can adjust cellOffset by subtracting the left insets so that the caret is immediately below the mouse, but the line index is still incorrect (^ = mouse; | = caret position after click).

abcd^efg
abcd|efg

That value, VirtualFlowHit#getCellIndex is calculated in VirtualFlow, not RTFX

[JordanMartinez]

Looking into it more, one just needs to adjust the x/y values to account for the inset values before calling virtualFow.hit(x, y).