praktikum-holons/src/holeg/ui/view/canvas/CanvasCollectionPanel.java

package holeg.ui.view.canvas;

import holeg.model.GroupNode;
import holeg.preferences.ImagePreference;
import holeg.ui.controller.Control;
import holeg.ui.view.image.Import;

import javax.swing.*;
import javax.swing.event.ChangeEvent;
import java.awt.*;
import java.util.HashMap;
import java.util.Map;
import java.util.Optional;

public class CanvasCollectionPanel extends JTabbedPane {
    private final Control control;
    private final Map<Component, Canvas> componentCanvasMap = new HashMap<>();
    private final Map<GroupNode, Component> groupNodeComponentMap = new HashMap<>();
    private Canvas main;
    private Canvas actual;

    public CanvasCollectionPanel(Control control) {
        this.control = control;
        control.OnShowGroupNode.addListener(this::showGroupNode);
        control.OnRemoveGroupNode.addListener(this::removeGroupNode);
        control.OnModelChanged.addListener(this::reset);
        createMainCanvas();
        this.addChangeListener(this::tabChangeEvent);
    }

    private void reset() {
        removeAll();
        componentCanvasMap.clear();
        groupNodeComponentMap.clear();
        createMainCanvas();
    }

    private void tabChangeEvent(ChangeEvent changeEvent) {
        Optional.ofNullable(componentCanvasMap.get(this.getSelectedComponent())).ifPresentOrElse(canvas -> {
            actual = canvas;
        }, () -> actual = main);
        control.clearSelection();
    }

    private void createMainCanvas() {
        GroupNode mainGroupNode = control.getModel().getCanvas();
        Canvas canvas = new Canvas(control, mainGroupNode);
        actual = main = canvas;
        final JScrollPane scrollPane = new JScrollPane(canvas);
        groupNodeComponentMap.put(mainGroupNode, scrollPane);
        componentCanvasMap.put(scrollPane, canvas);
        this.addTab("Main", scrollPane);
    }

    private void showGroupNode(GroupNode groupNode) {
        Optional.ofNullable(groupNodeComponentMap.get(groupNode))
                .ifPresentOrElse(this::setSelectedComponent,
                        () -> createNewCanvas(groupNode));
    }

    private void createNewCanvas(GroupNode groupNode) {
        Canvas canvas = new Canvas(control, groupNode);
        final JScrollPane scrollPane = new JScrollPane(canvas);
        groupNodeComponentMap.put(groupNode, scrollPane);
        componentCanvasMap.put(scrollPane, canvas);
        addTab(groupNode.getName(), scrollPane);
        setSelectedComponent(scrollPane);
        setTabComponentAt(this.indexOfComponent(scrollPane), new GroupNodeHeader(groupNode));
    }

    private void removeGroupNode(GroupNode groupNode){
        Optional.ofNullable(groupNodeComponentMap.get(groupNode))
                .ifPresent(scrollPane -> {
                    remove(scrollPane);
                    groupNodeComponentMap.remove(groupNode);
                });
    }

    public Canvas getActualCanvas() {
        return actual;
    }

    private class GroupNodeHeader extends JPanel {
        public GroupNodeHeader(GroupNode groupNode) {
            JLabel label = new JLabel(groupNode.getName());
            add(label);
            label.setBorder(null);
            label.setPreferredSize(new Dimension(label.getPreferredSize().width,8));
            this.setBorder(null);
            this.setOpaque(false);
            JButton button = new JButton(new ImageIcon(Import.loadImage(ImagePreference.Button.GroupNode.Close, 8,8)));
            button.setPreferredSize(new Dimension(8, 8));
            button.setBorder(null);
            add(button);
            button.addActionListener(clicked -> removeGroupNode(groupNode));
        }
    }
}