/*
* TimeTray
*
* TimeTray is a tool that adds a symbol to an operating system's icon tray
* showing the current calender week. Further information about date and time
* can be obtained by hovering over the symbol with the mouse pointer.
*
* TODO: open one presets window only
* TODO: positioning of the presets window
* TODO: color chooser settings
* TODO: font settings (maybe)
* TODO: beautify the settings window
* TODO: improve or remove the tooltip stuff
* TODO: refactoring, e.g. packaging
*
* @author Oliver Tacke, Armin Schöning
* @version 1.4, Feb 2016
*/

//import neccessary Classes
import java.awt.AWTException;
import java.awt.AlphaComposite;
import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics2D;
import java.awt.MenuItem;
import java.awt.PopupMenu;
import java.awt.RenderingHints;
import java.awt.SystemTray;
import java.awt.TrayIcon;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.IOException;
import java.io.PrintStream;
import java.nio.charset.Charset;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.Locale;
import java.util.Timer;
import java.util.TimerTask;
import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JSlider;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;

public class TimeTray extends TimerTask implements ActionListener {
// version string
private final String VERSION = "1.4";

// TrayIcon to be used in system tray
private TrayIcon trayIcon = null;

// dimension of the TrayIcon
private Dimension iconSize = null;

// internal Java calendar for getting date information
private Calendar calendar = null;

// current week number
private int weeknumber = 0;

// popupMenu to be used in connection with the TrayIcon
private PopupMenu menu = this.createMenu();

// Presets for the TrayIcon
private Presets presets = null;

/**
* main method
*
* @param args arguments
*/
public static void main(String[] args) {
// create new TrayIcon if a SystemTray is supported by the OS
if (SystemTray.isSupported()) {
new TimeTray();
} else {
// TODO: Display a "Sorry" message
}
}

/**
* TimeTray Constructor
*/
public TimeTray() {
// retrieve iconSize of SystemTray
SystemTray systemTray = SystemTray.getSystemTray();
iconSize = systemTray.getTrayIconSize();

// set presets
presets = new Presets(iconSize.height);

calendar = Calendar.getInstance();

// create TrayIcon according to iconSize
trayIcon = new TrayIcon(getTrayImage(), "TimeTray", menu);
try {
systemTray.add(trayIcon);
} catch (AWTException ex) {
ex.printStackTrace();
}

// run thread and set timer tooltip to update every second
run();

Timer timer = new Timer();
timer.schedule(this, 1000, 1000);
}

/**
* run method
*/
public void run() {
// get current date and time and set ToolTipText accordingly
calendar = Calendar.getInstance();

trayIcon.setToolTip(
"week " +
getWeekNumber() + ", " +
presets.sdf.format(calendar.getTime()));

// The computer might be running when a new week starts...
if (weeknumber != getWeekNumber()) {
weeknumber = getWeekNumber();
repaintTrayIcon();
}
}

/**
* create the image for the TrayIcon
*
* @returns BufferedImage the image for the TrayIcon
*/
private BufferedImage getTrayImage() {
BufferedImage image = new BufferedImage(
this.iconSize.width,
this.iconSize.height,
BufferedImage.TYPE_INT_ARGB);

// draw background image
Graphics2D g2 = image.createGraphics();
g2.setColor(presets.backgroundColor);
g2.fillRect(0, 0, iconSize.width, iconSize.height);

// draw number
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
RenderingHints.VALUE_ANTIALIAS_ON);
g2.setColor(presets.fontColor);
g2.setFont(presets.font);
FontMetrics fm = g2.getFontMetrics(presets.font);
int fontWidth = fm.stringWidth(
String.valueOf(getWeekNumber()));
g2.drawString(
String.valueOf(getWeekNumber()), (iconSize.width - fontWidth) / 2,
iconSize.height - 3);

return image;
}

private void repaintTrayIcon() {
this.trayIcon.setImage(this.getTrayImage());
}

/**
* calculate the current week number
*
* @return int the current week number
*/
private int getWeekNumber() {
return this.calendar.get(Calendar.WEEK_OF_YEAR) + this.presets.offset;
}

/**
* ActionListener for the TrayIcon
*
* @param e the event triggering the ActionListener
*/
public void actionPerformed(ActionEvent ev) {
// user chose to exit TimeTray
if (ev.getActionCommand() == "quit") {
System.exit(0);
}
// user requests information about TimeTray
if (ev.getActionCommand() == "settings") {
SettingsWindow settingsWindow = new SettingsWindow(this);
settingsWindow.setVisible(true);
}
}

/**
* creates a PopUp menu for the TrayIcon
*
* @return PopUp menu for the TrayIcon
*/
private PopupMenu createMenu() {
PopupMenu menu = new PopupMenu("TimeTray " + this.VERSION);

// about item
MenuItem menuSettings = new MenuItem("Settings");
menuSettings.setActionCommand("settings");
menu.add(menuSettings);

// exit item
MenuItem menuExit = new MenuItem("Quit");
menuExit.setActionCommand("quit");
menu.add(menuExit);

menu.addActionListener(this);

return menu;
}

/**
* individual settings or sets default values (not yet)
*
* TODO: setters/getters
*/
private class Presets {

// path + file name for saving settings in the home directory
private final String FILENAME = System.getProperty("user.home") +
File.separator +
".timetray";

// default background color for the tray icon
private final Color DEFAULT_BACKGROUND_COLOR =
new Color(221, 221, 221, 0);

// default font color for the tray icon
private final Color DEFAULT_FONT_COLOR = Color.white;

// in general, locale settings probably match the local customs
private static final int DEFAULT_OFFSET = 0;

// default format for displaying date information
private static final String DEFAULT_SDF_FORMAT =
"EEEE, MMMM dd, yyyy, HH:mm";

// background color for the tray icon
private Color backgroundColor;

// font color for the tray icon
private Color fontColor;

// font to be used
private Font font;

/*
* used to correct the calendar week by +1 or -1 if neccessary
*
* this may come in handy, because Java determines the start of a week
* depending on the locale settings of your operating system that can
* differ from the customs of your region.
*/
private int offset;

// SimpleDateFormat for use in connection with the ToolTip text
private SimpleDateFormat sdf;

private Presets(int trayHeight) {
/*
* I use "SansSerif" instead of "Arial" because this tool might run
* anywhere, not only Windows
*/
final Font DEFAULT_FONT =
new Font("SansSerif", Font.PLAIN, trayHeight);

backgroundColor = this.DEFAULT_BACKGROUND_COLOR;
fontColor = this.DEFAULT_FONT_COLOR;
font = DEFAULT_FONT;
offset = this.DEFAULT_OFFSET;
sdf = new SimpleDateFormat(DEFAULT_SDF_FORMAT);

File file = new File(this.FILENAME);
if (file.exists()) {
loadPresets(trayHeight);
} else {
savePresets();
}
}

/**
* Load presets
*
* This load/save method is very ugly, I know. No beauty and not
* failsafe. It might be replaced by something using JSON, but I want
* to avoid using full blown libraries for a plain settings file.
*
* @param int trayHeight the height of the TrayIcon
*/
private void loadPresets(int trayHeight) {
String line;
try (
InputStream fis = new FileInputStream(this.FILENAME); InputStreamReader isr = new InputStreamReader(
fis,
Charset.forName("UTF-8")); BufferedReader br = new BufferedReader(isr);
) {
int red = Integer.parseInt(br.readLine());
int green = Integer.parseInt(br.readLine());
int blue = Integer.parseInt(br.readLine());
int alpha = Integer.parseInt(br.readLine());
this.backgroundColor = new Color(red, green, blue, alpha);

red = Integer.parseInt(br.readLine());
green = Integer.parseInt(br.readLine());
blue = Integer.parseInt(br.readLine());
alpha = Integer.parseInt(br.readLine());
this.fontColor = new Color(red, green, blue, alpha);

this.offset = Integer.parseInt(br.readLine());

String family = br.readLine();
int style = Integer.parseInt(br.readLine());
this.font = new Font(family, style, trayHeight);

this.sdf = new SimpleDateFormat(br.readLine());

} catch (IOException ex) {
ex.printStackTrace();
}
}

/**
* Save presets
*
* This load/save method is very ugly, I know. No beauty and not
* failsafe. It might be replaced by something using JSON, but I want
* to avoid using full blown libraries for a plain settings file.
*/
private void savePresets() {
try (PrintStream out = new PrintStream(
new FileOutputStream(this.FILENAME))) {
out.println(this.backgroundColor.getRed());
out.println(this.backgroundColor.getGreen());
out.println(this.backgroundColor.getBlue());
out.println(this.backgroundColor.getAlpha());

out.println(this.fontColor.getRed());
out.println(this.fontColor.getGreen());
out.println(this.fontColor.getBlue());
out.println(this.fontColor.getAlpha());

out.println(this.offset);

out.println(this.font.getFamily());
out.println(this.font.getStyle());

out.println(this.sdf.toPattern());

} catch (FileNotFoundException ex) {
ex.printStackTrace();
}
}
}

/**
* Window for changing the settings
*/
private class SettingsWindow extends JFrame implements ChangeListener {
// Tray
private TimeTray parent;

// Slider for setting the offset
private JSlider offsetSlider;

/**
* Constructor for SettingsWindow
*
* @param TimeTray parent Tray opening the window
*/
private SettingsWindow(TimeTray parent) {
this.parent = parent;
this.getContentPane().setLayout(new BoxLayout(
this.getContentPane(),
BoxLayout.PAGE_AXIS));
this.initWindow();
}

/**
* Build the window
*/
private void initWindow() {
JLabel sliderLabel = new JLabel("Offset");
sliderLabel.setAlignmentX(Component.LEFT_ALIGNMENT);

offsetSlider = createOffsetSlider(this);

this.setTitle("Presets (not finished)");
this.getContentPane().add(sliderLabel);
this.getContentPane().add(Box.createRigidArea(
new Dimension(0, 5)));
this.getContentPane().add(offsetSlider);
this.pack();
}

/**
* Build the slider for setting the offset
*
* @param SettingsWindow window the window that implements the Change
* Listener
* @return JSlider the slider for setting the offset
*/
private JSlider createOffsetSlider(SettingsWindow window) {
JSlider offsetSlider = new JSlider(
JSlider.HORIZONTAL, -1,
1,
window.parent.presets.offset);
offsetSlider.setAlignmentX(Component.LEFT_ALIGNMENT);
offsetSlider.setMajorTickSpacing(1);
offsetSlider.setPaintTicks(true);
offsetSlider.addChangeListener(window);
offsetSlider.setPaintLabels(true);

return offsetSlider;
}

/**
* register change events in the window
*
* @param ChangeEvent an event
*/
public void stateChanged(ChangeEvent ev) {
JSlider source = (JSlider) ev.getSource();
this.parent.presets.offset = source.getValue();

//update the TrayIcon image
this.parent.repaintTrayIcon();

// save changed presets
this.parent.presets.savePresets();
}
}
}