/*
 * Copyright 2014 dorkbox, llc
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package dorkbox.util.tray.swing;

import dorkbox.util.ScreenUtil;
import dorkbox.util.SwingUtil;
import dorkbox.util.tray.MenuEntry;
import dorkbox.util.tray.SystemTrayMenuAction;
import dorkbox.util.tray.SystemTrayMenuPopup;

import javax.swing.ImageIcon;
import javax.swing.JMenuItem;
import java.awt.AWTException;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Image;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.SystemTray;
import java.awt.TrayIcon;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;

/**
 * Class for handling all system tray interaction, via SWING
 */
public
class SwingSystemTray extends dorkbox.util.tray.SystemTray {
    volatile SystemTrayMenuPopup menu;
    volatile JMenuItem connectionStatusItem;

    volatile SystemTray tray;
    volatile TrayIcon trayIcon;

    /**
     * Creates a new system tray handler class.
     */
    public
    SwingSystemTray(final String iconName) {
        super();
        SwingUtil.invokeAndWait(new Runnable() {
            @Override
            public
            void run() {
                SwingSystemTray.this.tray = SystemTray.getSystemTray();
                if (SwingSystemTray.this.tray == null) {
                    logger.error("The system tray is not available");
                }
                else {
                    SwingSystemTray.this.menu = new SystemTrayMenuPopup();

                    String iconPath = iconPath(iconName);
                    Image trayImage = new ImageIcon(iconPath).getImage()
                                                             .getScaledInstance(TRAY_SIZE, TRAY_SIZE, Image.SCALE_SMOOTH);
                    trayImage.flush();
                    final TrayIcon trayIcon = new TrayIcon(trayImage);
                    SwingSystemTray.this.trayIcon = trayIcon;

                    // appindicators don't support this, so we cater to the lowest common denominator
//                    trayIcon.setToolTip(SwingSystemTray.this.appName);

                    trayIcon.addMouseListener(new MouseAdapter() {
                        @Override
                        public
                        void mousePressed(MouseEvent e) {
                            final SystemTrayMenuPopup menu = SwingSystemTray.this.menu;
                            Dimension size = menu.getPreferredSize();

                            Point point = e.getPoint();
                            Rectangle bounds = ScreenUtil.getScreenBoundsAt(point);

                            int x = point.x;
                            int y = point.y;

                            if (y < bounds.y) {
                                y = bounds.y;
                            }
                            else if (y + size.height > bounds.y + bounds.height) {
                                // our menu cannot have the top-edge snap to the mouse
                                // so we make the bottom-edge snap to the mouse
                                y -= size.height; // snap to edge of mouse
                            }

                            if (x < bounds.x) {
                                x = bounds.x;
                            }
                            else if (x + size.width > bounds.x + bounds.width) {
                                // our menu cannot have the left-edge snap to the mouse
                                // so we make the right-edge snap to the mouse
                                x -= size.width; // snap to edge of mouse
                            }

                            // weird voodoo to get this to popup with the correct parent
                            menu.setInvoker(menu);
                            menu.setLocation(x, y);
                            menu.setVisible(true);
                            menu.requestFocus();
                        }
                    });

                    try {
                        SwingSystemTray.this.tray.add(trayIcon);
                    } catch (AWTException e) {
                        logger.error("TrayIcon could not be added.", e);
                    }
                }
            }
        });
    }


    @Override
    public
    void shutdown() {
        SwingUtil.invokeAndWait(new Runnable() {
            @Override
            public
            void run() {
            SwingSystemTray.this.tray.remove(SwingSystemTray.this.trayIcon);

            synchronized (SwingSystemTray.this.menuEntries) {
                for (MenuEntry menuEntry : SwingSystemTray.this.menuEntries) {
                    menuEntry.remove();
                }
                SwingSystemTray.this.menuEntries.clear();
            }

            SwingSystemTray.this.connectionStatusItem = null;
            }
        });
    }

    @Override
    public
    void setStatus(final String infoString) {
        SwingUtil.invokeLater(new Runnable() {
            @Override
            public
            void run() {
                if (SwingSystemTray.this.connectionStatusItem == null) {
                    final JMenuItem connectionStatusItem = new JMenuItem(infoString);
                    Font font = connectionStatusItem.getFont();
                    Font font1 = font.deriveFont(Font.BOLD);
                    connectionStatusItem.setFont(font1);

                    connectionStatusItem.setEnabled(false);
                    SwingSystemTray.this.menu.add(connectionStatusItem);

                    SwingSystemTray.this.connectionStatusItem = connectionStatusItem;
                }
                else {
                    SwingSystemTray.this.connectionStatusItem.setText(infoString);
                }
            }
        });
    }

    @Override
    public
    void setIcon(final String iconName) {
        SwingUtil.invokeLater(new Runnable() {
            @Override
            public
            void run() {
                String iconPath = iconPath(iconName);
                Image trayImage = new ImageIcon(iconPath).getImage()
                                                         .getScaledInstance(TRAY_SIZE, TRAY_SIZE, Image.SCALE_SMOOTH);
                trayImage.flush();
                SwingSystemTray.this.trayIcon.setImage(trayImage);
            }
        });
    }

    /**
     * Will add a new menu entry, or update one if it already exists
     */
    @Override
    public
    void addMenuEntry(final String menuText, final String imagePath, final SystemTrayMenuAction callback) {
        if (menuText == null) {
            throw new NullPointerException("Menu text cannot be null");
        }

        SwingUtil.invokeLater(new Runnable() {
            @Override
            public
            void run() {
                synchronized (menuEntries) {
                    MenuEntry menuEntry = getMenuEntry(menuText);

                    if (menuEntry != null) {
                        throw new IllegalArgumentException("Menu entry already exists for given label '" + menuText + "'");
                    }
                    else {
                        menuEntry = new SwingMenuEntry(menu, menuText, imagePath, callback, SwingSystemTray.this);
                        menuEntries.add(menuEntry);
                    }
                }
            }
        });
    }
}