package com.example.client.utils;


import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.event.KeyListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionAdapter;
import java.awt.event.MouseMotionListener;

import javax.swing.BorderFactory;
import javax.swing.DefaultListCellRenderer;
import javax.swing.JComboBox;
import javax.swing.JComponent;
import javax.swing.JLabel;
import javax.swing.JList;
import javax.swing.JPopupMenu;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.MenuSelectionManager;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;
import javax.swing.plaf.ComboBoxUI;
import javax.swing.plaf.basic.ComboPopup;
import javax.swing.plaf.metal.MetalComboBoxUI;
import javax.swing.tree.TreeCellRenderer;
import javax.swing.tree.TreeNode;
import javax.swing.tree.TreePath;

/**
 * 下拉树工具类
 * 2019年9月16日15:20:18
 * @author Administrator
 *
 */
@SuppressWarnings("serial")
public class DownTheTree extends JComboBox{
    /**
     * 显示用的树
     */
    private JTree tree;

    public DownTheTree() {
        this(new JTree());
    }

    public DownTheTree(JTree tree) {
        this.setTree(tree);
    }

    /**
     * 设置树
     *
     * @param tree
     *            JTree
     */
    public void setTree(JTree tree) {
        this.tree = tree;
        if (tree != null) {
            this.setSelectedItem(tree.getSelectionPath());
            this.setRenderer(new JTreeComboBoxRenderer());
        }
        this.updateUI();
    }

    /**
     * 取得树
     *
     * @return JTree
     */
    public JTree getTree() {
        return tree;
    }

    /**
     * 设置当前选择的树路径
     *
     * @param o
     *            Object
     */
    public void setSelectedItem(Object o) {
        tree.setSelectionPath((TreePath) o);
        getModel().setSelectedItem(o);
    }

    public void updateUI() {
        ComboBoxUI cui = (ComboBoxUI) UIManager.getUI(this);
        if (cui instanceof MetalComboBoxUI) {
            cui = new MetalJTreeComboBoxUI();
        }
        setUI(cui);
    }

    // UI Inner classes -- one for each supported Look and Feel
    class MetalJTreeComboBoxUI extends MetalComboBoxUI {
        protected ComboPopup createPopup() {
            return new TreePopup(comboBox);
        }
    }


    /**
     *
     * Description: 树形结构而来的DefaultListCellRenderer
     */
    class JTreeComboBoxRenderer extends DefaultListCellRenderer {
        public Component getListCellRendererComponent(JList list, Object value,
                                                      int index, boolean isSelected, boolean cellHasFocus) {
            if (value != null) {
                TreePath path = (TreePath) value;
                TreeNode node = (TreeNode) path.getLastPathComponent();
                value = node;
                TreeCellRenderer r = tree.getCellRenderer();
                JLabel lb = (JLabel) r.getTreeCellRendererComponent(tree,
                        value, isSelected, false, node.isLeaf(), index,
                        cellHasFocus);
                return lb;
            }
            return super.getListCellRendererComponent(list, value, index,
                    isSelected, cellHasFocus);
        }
    }

    /**
     * 测试
     */
/*    public static void main(String args[]) {
        JFrame frame = new JFrame("JTreeComboBox 例子");
        frame.setSize(400, 320);
        Dimension d = Toolkit.getDefaultToolkit().getScreenSize();
        frame.setLocation((d.width - frame.getSize().width) / 2,
                (d.height - frame.getSize().height) / 2);
        frame.getContentPane().setLayout(new FlowLayout());
        final DownTheTree box = new DownTheTree(new JTree());
        box.setPreferredSize(new Dimension(300, 21));
        frame.getContentPane().add(box);
        frame.setVisible(true);
    }*/
}

/**
 * <p>
 * Description: TreePopup
 * </p>
 */
@SuppressWarnings("serial")
class TreePopup extends JPopupMenu implements ComboPopup {
    protected DownTheTree comboBox;
    protected JScrollPane scrollPane;

    protected MouseMotionListener mouseMotionListener;
    protected MouseListener mouseListener;
    private MouseListener treeSelectListener = new MouseAdapter() {
        public void mouseReleased(MouseEvent e) {
            JTree tree = (JTree) e.getSource();
            TreePath tp = tree.getPathForLocation(e.getPoint().x,
                    e.getPoint().y);
            if (tp == null) {
                return;
            }
            comboBox.setSelectedItem(tp);
            togglePopup();
            MenuSelectionManager.defaultManager().clearSelectedPath();
        }
    };

    public TreePopup(JComboBox comboBox) {
        this.comboBox = (DownTheTree) comboBox;
        setBorder(BorderFactory.createLineBorder(Color.black));
        setLayout(new BorderLayout());
        setLightWeightPopupEnabled(comboBox.isLightWeightPopupEnabled());
        JTree tree = this.comboBox.getTree();
        if (tree != null) {
            scrollPane = new JScrollPane(tree);
            scrollPane.setBorder(null);
            add(scrollPane, BorderLayout.CENTER);
            tree.addMouseListener(treeSelectListener);
        }
    }

    public void show() {
        updatePopup();
        show(comboBox, 0, comboBox.getHeight());
        comboBox.getTree().requestFocus();
    }

    public void hide() {
        setVisible(false);
        comboBox.firePropertyChange("popupVisible", true, false);
    }

    protected JList list = new JList();

    public JList getList() {
        return list;
    }

    public MouseMotionListener getMouseMotionListener() {
        if (mouseMotionListener == null) {
            mouseMotionListener = new MouseMotionAdapter() {
            };
        }
        return mouseMotionListener;
    }

    public KeyListener getKeyListener() {
        return null;
    }

    public void uninstallingUI() {
    }

    /**
     * Implementation of ComboPopup.getMouseListener().
     *
     * @return a <code>MouseListener</code> or null
     * @see ComboPopup#getMouseListener
     */
    public MouseListener getMouseListener() {
        if (mouseListener == null) {
            mouseListener = new InvocationMouseHandler();
        }
        return mouseListener;
    }

    protected void togglePopup() {
        if (isVisible()) {
            hide();
        } else {
            show();
        }
    }

    protected void updatePopup() {
        setPreferredSize(new Dimension(comboBox.getSize().width, 200));
        Object selectedObj = comboBox.getSelectedItem();
        if (selectedObj != null) {
            TreePath tp = (TreePath) selectedObj;
            ((DownTheTree) comboBox).getTree().setSelectionPath(tp);
        }
    }

    protected class InvocationMouseHandler extends MouseAdapter {
        public void mousePressed(MouseEvent e) {
            if (!SwingUtilities.isLeftMouseButton(e) || !comboBox.isEnabled()) {
                return;
            }
            if (comboBox.isEditable()) {
                Component comp = comboBox.getEditor().getEditorComponent();
                if ((!(comp instanceof JComponent))
                        || ((JComponent) comp).isRequestFocusEnabled()) {
                    comp.requestFocus();
                }
            } else if (comboBox.isRequestFocusEnabled()) {
                comboBox.requestFocus();
            }
            togglePopup();
        }
    }
}